BLV mgn12 3D Printer mod for Anet A8 / AM8 / Prusa I3 clone

by Blv, published

BLV mgn12 3D Printer mod for Anet A8 / AM8 / Prusa I3 clone by Blv Oct 21, 2017


BLV mgn12 mod for Anet A8 / AM8

  • The main purpose of this project is: converting your Anet A8 into an incredible 3d printer, using MGN12 rails fixed on an aluminium extrusion frame.

  • This upgrade compatible with pheneeny's AM8 mod with small changes. (Huge credit!)

  • Why mgn?
    The linear bearing and Delrin Wheel Gantry commonly used at most of low-mid 3d printers as a cheaper solution for linear motion. Its cheaper replacement for the expensive mgn rails BUT price is at the expense of accuracy and reliability. Well, linear guided rails (mgn rails) are much more rigid, extreme precise and smooth then linear bearing or Delrin. The linear rails lets you print with higher speed - shorting print time without compromising print quality. The fact rails are fixed to frame prevents unwanted motion related to bent threaded rods or other axis's motion. There seems to be a good reason why they are mostly used with high end 3d printers..
    So, i found cheap chinese mgn rails at Aliexpress and thought to myself why not?


fixing the mgn rails can be very frustrating. it need to be perfectly aligned and straight.
else, it will give you a headache, so don't start this project without tons of patience.

  • design flexibility and Source file
    I'm sharing with you the source file of this project in order to improve the design and make it even more better. you will find the STEP file inside the project zip.
    Please follow the item license (under the Creative Commons - Attribution - Non-Commercial - Share Alike.).
  • If you are using the STEP file, please don't forget to mark it as a Remix :)

  • Also made for this project a Build plate for simplify3d

Please notice you may need to re-center bed coordinates via marlin configuration
or change Z extrusion position to center the hotbed

Build it at your own risk.

Latest video update
A quick peek at my project building progress.
sorry for all the exposed wires - i had to test it. first video after all axis's electronics had been connected. Next week i'll get the 400mm threaded rods and install the rest.
I had to reverse x-motor connector in this video beacuse mistakly i fixed the carriage screw on the back instead on the front (i fixed and uploaded the fixed x carriage).

  • Seeing all of this great community members uploading photos and remixes worth all of the long hours that i have put into this project :)
    I will appreciate if you could please upload an "I made one" photos :)
    Thank you guys !!!


  • 3/2/18 Added a PDF file with all the offset measurements for Hotend and sensors.
  • 7/1/18 All STEP files updated including: Main Printer, Cube carriage and MK3 carriage.
    (If you are using it, i will appreciate if you could please mark it as a REMIX)
  • 6/1/18 New experimental Cube carriage supports V6/Clone BLtouch, 8mm/12mm Sensor (required 4010 blower fan). (inspired by CR-10)
  • 6/1/18 New MK3 carriage made for Prusa original MK3 nuzzle fan support BLtouch, 8mm/12mm Sensor. I Love this Carriage !!
  • 6/1/18 New X-screw holder extended
  • 6/1/18 New holders made for 30A/29A 360W power supply.
  • 6/1/18 New X motor holder added a 4010 fan holder to cool the X motor on higher speeds.
  • 6/1/18 New 4010 Spitfire style fan cover for the New X motor holder.
  • 6/1/18 Modified the rear corners which allows threading cables through extrusions.
  • 8.12/17 improved bed adapters for better slicing process.
  • 25/11/17 added 2 type of Jigs that helps aligning the mgn12 rails
  • 17/11/17 added a new experimental carriage adapter for Anet A8 Original carriage
    STEP file updated ! (can be edited with any CAD software exp: fusion360)
    added X-motor cover+cable holder (infill 65%+)
  • 05/11 added X-Carriage for E3D Chimera Hotend
  • 02/11 new LED strip holder (compatible with regular 9.8mm strip width)
    new rubber feet mount instead of the tapped method. (Print with 60% infill)
    new improved X-Carriage (added on both sides cable holder)
  • 28/10 BOM updated
  • 27/10 added Heated bed Belt locker (belt_lock_infill80.stl) (infill 80%+)
  • 26/10 fixed x-carriage (the belt holder holes are now on front - reveres x motor not needed any more)
  • 23/10 BOM list updated (added solution for AM8 with 440mm z extrusion)
  • 22/10 added Cad Source file due to community request (BLV Mgn12 mod.step).
    added BOM file (pdf)
    added printing orientation images

Quick video: It's alive :) the first axis test..

Choose your Style

Mod variations:

You have the ability to choose your own style:

  1. Anet A8 converted to AM8 (original height: 440mm)+ BLV mgn12 mod:
    If you are already a proud owner of an AM8 printer and don't want to change the orignal height, you will have to get a 350mm rails instead of 400mm .

  2. Anet A8 converted to AM8 + Higher Z-axis (height: 500mm) + BLV mgn12 mod:
    First you will have to build an AM8 with a small changes:

    • instead of: 2x440mm 2040 extrusion > replace with: 2x500mm 2040 extrusion or bigger.
    • instead of: 2x340mm 2040 extrusion > replace with: 4x364mm 2040 extrusion
    • get a longer threaded rods 400mm.
      obviously, you don't need to print all AM8 parts but some (more info at printing info section)
  3. Anet AM8 + Free style + BLV mgn12 mod:
    As i mentioned, the design is flexible and includes separated parts that can be fitted to your wish. if you want custom size printer with a bigger bed or higher Z-axis, please choose wisely your own extrusion size and attached the modular parts to your desired extrusion.

Requirements & BOM


  1. Anet A8 printer > AM8
  2. Tools
  3. Technical ability
  4. spare time

BOM - parts you need

clarification: BOM includes AM8 BOM.

  • 7 x Mgn12H Carriage (4 for Y-axis, 1 for X-axis, 2 for Z axis)
  • 3 x 2040 extrusion 313mm (for top, front, back)
  • 4 x 2040 extrusion 364mm (Y-axis)
  • 1 x 2020 extrusion 420mm (x-axis)
  • 2 x 608zz bearing (optional: if you intend using the top threaded rod holders)
  • 16 x HBLFSNF5 Corner Bracket
  • 150 x M5X10 Button Head Socket Cap Screw
  • 8 x M5x10 Socket Head Cap Screw
  • 6 x M5x16 Socket Head Cap Screw
  • 4 x M3X20 Socket Head Cap Screw
  • 60 x M3X8 Socket Head Cap Screw
  • 1 x M4X30 hex head (y-tensioner button)
  • 6 x M3X20 screw
  • 1 x M3X32 screw
  • 20 x M4X10 screw
  • 160 x M5 T-nut or M5x.8 Square Nut
  • 40 x M3 T-nut
  • 4 x M3 nut
  • 13 x M3 Washer
  • 1 x M3 nylock
  • 20 x M4 nut
  • 20 x M4 washer
  • 6 x Rubber Feet
  • 2 x GT2 16T idler (3mm bore)
  • 1 x 5 meters GT2 reinforced fiberglass belt 6mm wide pitch 2mm
  • 1 x PC4-M6 OD4mm (optional: if using greg's geard extruder)

for option 1 (original AM8 size):

  • 2 x 2040 extrusion 440mm (z axis)
  • 3 x Mgn12 350mm rail (x & z axis)
  • 2 x Mgn12 400mm rail (y axis)

for option 2 (extended z height):

  • 4 x Mgn12 400mm rail
  • 1 x Mgn12 360mm or 350mm rail
  • 2 x 2040 extrusion 500mm (z axis)
  • 2 x Threaded Rods 400mm

Additional electronics BOM

  • 1 x e3d v6 hotend or Clone
  • 1 x e3d Chimera hot end

What & How to print

Part to print from this BLV mgn12 mod project:
print all except those optional parts:

  • Y mount motor - (print this part only if you dont have the AM8 Y motor mount)
  • Top z holders - (aka anti z-wobble) (holders may limit Z height and they are not really needed)
  • Caliper Holder - (print only if you have a digital metal caliper)
  • LCD case and brackets - (print it only if you have a reprap Discount LCD 12864 only, else use the original AM8 lcd case and brackets)

Part to print from AM8:

  • 1 x 1_LCD_Base_Left (only if you are planing to use the original Anet A8 lcd)
  • 1 x 1_LCD_Base_Right (only if you are planing to use the original Anet A8 lcd)
  • 1 x 1_LCD_Case_Top (only if you are planing to use the original Anet A8 lcd)
  • 1 x 1_PSU_Mount (for Original Anet PSU)
  • 1 x 1_Wire_Holder
  • 2 x 2_Bottom_Tee_Plate
  • 2 x 2_Top_Corner_Plate
  • 4 x 4_Bottom_Corner_Plate
  • 1 x Anet_Board_Mount__With_Fan (dont print if you choose the electronics box)
  • 1 x Anet_Board_Mount_No_Fan (dont print if you choose the electronics box)

Material and Infill

Inside zip file you will find a PDF file named: BLV mgn12 mod.pdf
which contain full spec of the Parts (name, material to print with and infill percentage).

Printing orientation

Highly important: i added 4 pictures showing printing orientation of the prats.
the printing orientation is very important because it contributes to the strength of the items.

  • make sure before printing that its calibrated since the dimension precision are crucial !

view original size: open it in a new windows and save the image or use the pdf file inside the zip files

view original size: open it in a new windows and save the image or use the pdf file inside the zip files

Assembly instructions

  1. Assemble the frame extrusion according to pheneeny's AM8 mod
    at the AM8 mod files you will find also the prefect guide pheneeny made for assemby.

  2. Assemble the BLV mgn12 mod according to assembly instructions that found in this project zip file. its a pdf file named:BLV mgn12 mod.pdf. the file contains sketch with all
    the main parts.

  3. I made an assembly video in order to explain how to assemble: Bed adapters, X-axis components, Cube carriage and V6 carriage. On this video i mentioned a 5010 blower fan but i was wrong- I meant for 5015 fan (Thank you Craig).
    Please notice you may need re-center the hotend/bed coordinates via marlin configuration.

Additional Parts

Additional Optional Parts

MGN12 rails & Carriages extra info

MGN Rails

Well, i used a cheap Chinese mgn12 rails from aliexpress cost 20$ each.
The store i bought it from named: "Mellow" via aliexpress. Before that i bought from other store named: "linkcnc Store" and the rails was awful! it was a used rails, damaged and shorter then what i ordered. They ware so awful, that even after cleaning and lubricating it was still stuck and jammed.

Cleaning and lubricating

notice that the mgn rails you'll get will not be smooth as it should be.
at the factory they lubricate it with a protecting oil that need to be cleaned away.
There are some videos on YouTube showing how to clean the carriage with WD-40.
don't forget that after cleaning both rails and carriage, you will have to lubricate it with sewing machine oil.
As for smoothness: Please ignore the method for testing smoothness but tilting the rail - its wrong! You want it to be smooth but not too much.
Also, since its a miniature rails, please don't use thick grease to lubricate.

Adittional links

Cleaning mgn12 carriage video:
Although the video in russian language which i don't understand - its a pretty good video. just use a container in order not to lose steel balls

note: after assembling all steel balls, you will be left with empty space of one steel ball.

Rails installation:


  • fixing the rail can very frustrating, you will have to re adjust it a few times until the rail will be leveled and straight.
  • the mgn bed adapters needs to be fixes with screws to the heated bead carriage - screws must be tighten in cross like in anet a8 manual.
  • take your time an adjust until it will be even from both sides then the motion will be smooth.
    its very tricky and need a lot of patience.

Small demonstration video

Note: The motor in the video is incompatible. it was installed only for taking the video and testing the weight.

view original size: open it in a new windows and save the image or use the pdf file inside the zip files

view original size: open it in a new windows and save the image or use the pdf file inside the zip files

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Comments deleted.

Hello. Very nice project, I'm doing it right now but I'm stopped trying to understand how the Y endstop works. If I place on the back profile, the micro didn't reach the plate. May you give a pict of your setup?


Of course, tomorrow i will take some pictures for you :)

Many thanks! I'll wait for your picture.


This is such a beautiful design! I’ve always loved mgn12 rails as they’re more silent and precise. Thank you!

Made. And made. Thank you BLV!

Thank you Krame !!!
You have made a really good job with your "HULK" printer (since its green :) )
I really appreciate that you have shared the photos of your beauty
Thank you :)

Hi, what nema engine model do you recommend to build this printer.
I would like to keep my anet a8 in working order.

Hi :)

If you would like to keep the Anet A8 and build another printer, then
i highly recommend SingaSong Nema 17 17HS4401 stepper motor. Its much better then the
original Anet A8 motors and much more cooler when using a tmc2130/tmc2208 stepper drivers.
5pcs can cost you 38$ (Cheap and reliable) Search at Aliexpress for item: 32376023464

Enjoy :)

Thank you.
It is ordered,..

however, I saw that the axis of these engines was 5mm.
On the nomenclature you indicate pulleys with a 3mm axis
2 x GT2 16T idler (3mm bore)
you need pulleys with a 5mm axis?


The 5mm pulleys are for the motors shafts
And the 3mm are for the idler, such as the one that goes into the tensioner

The 5mm Pulleys are only for the stepper motor shaft and the 3mm are idler pulleys.

Yes that's right.
Sorry for the mistake.

glad to help bud :)

My stock Anet A8 got knocked off my table by my kids and a few frame parts broke/cracked. Was looking to replace it with this setup. Would anyone be willing to help me out with printing the parts to perform this upgrade? Im kinda angry this happened but life happens i guess. I will compensate for material used. Message me if you can help me out.


Yes, I can help if you still need it.

that would be great

Hi ! would like to build one of this , and can you help me with the length for the extrusion that I need to build ? what in my mine is prefer to print 300x300 and high is 500 and above , can you give me the build length for it , I mean the length of the extrusion , mgn12 rail and the threat rod and etc ...
Thank you :)

I have a problem of offset printing, how to center my nozzle for printing ??
I use marlin

Hi :)
It's very easy to fix.
There are many Youtube guiding video tutorials about centering the bed. Just follow one of the video guides.
Please notice that inside the zip folder you will find file named: dimensions.pdf
This file include all the needed numbers/dimensions in order to center your bed.

ok i m on the start of printing the parts needed apart from the am8 which i allready have.....and i have this question about
what filament to use..iguess most of the parts will be pla and some parts will be abs or other......the thing is that i have a lot of pla and i want
to use it.....which parts are the critical to print with abs ???????because i do have to buy some.....all of them ??? thanks and great job again

Hi my friend :)
Inside the zip file you will find BLV_mgn12_mod.pdf file, there you will find next to most of the parts the recommended material.
My personal recommendation is to use PETG/ABS with most of the parts that there is a load on them or next to hot area such as motors and bed. (bed adapters, tensioners, mounts and so on.. )

ok thanks i will print in abs,i have not tried petg before and i m not use ti it.....i dont know if its easier or not

Is there a cable chain available for this awsome thing? I couldn't find one in the files. I don't want have my cables hanging over the printer.

Hi, I found a problem with your Fan Duck.
When the cooling starts, the temperature drops to 180 ° and does not rise because the inclination of the fan duck is towards the sensor.
I made several changes, then I found another solution. I have also raised the fan plug to avoid out of air.

.It seems to work well

Hi my friend :)
Its seems that we are having here a misunderstanding..
I think that you are using the wrong fan duct. Its definitely doesn't look like Prusa mk3 circular which i designed the carriage to suite for.
as i wrote at the description: "New MK3 carriage made for Prusa original MK3 nuzzle fan ..."
Please enter this link: https://www.thingiverse.com/thing:2712591 and download the correct fan duct (i've attached an image).
personally i think that prusa fan duct is the best..
Please notice that you will have to do an Auto PID while your fan is ON in order to get the accurate temperature at PID process.

Prusa i3 MK3
by Kissman

Hi, I did a remix of the MK3 pieces. I made a 40 ° bend to put a 40mm fan

great solution for better cooling!

I have everything currently ordered to build this, but I want to go with a direct drive titan with an E3D V6 hot end, and bltouch. Is this a possibility, currently, or will I have to modify things myself? I was thinking about trying to do dual titan/E3Dv6's, but that would probably be too much to hope for here. :D.

Hi Techrev
In order to use titan you will have to modify it.
but in case you will want to use chimera (2 hotend) there is already a remix for it :)

Chimera Clone Mount

Thanks :D. I don't know that will work for me as I already have 2 titan extruders and 2 e3d v6 hot ends that I want to use. I will try remixing this, maybe, to work with the carriage and see if it's ok https://www.thingiverse.com/thing:2240611 Otherwise I guess it will probably be trying out bowden. Bowden seems to be good, but I've heard it doesn't work well with some materials.

Dual E3D Titan Aero

Hello and sorry. I'm starting with the testing of mine (iron version).
Could you make the MK £ attack for the Chimera in the future? Thank you.

Hi bud :)
There are remixes for the chimera carriage.

the MK3_V6_hugger.stl does not slice correctly in S3D

Which version you are using?
Try slice it from the other side

Discovered same issue - printing it from the the other side works

Very Impressive!

I am wondering about the synchronization between the Z axis motors, does the extrusion and linear rails essentially prevent any synch issues?

The Z axis motors connected as parallel
there is no notice desynchronization between them, unless you put some force or manual changed the z axis position with tour hand.
The anet A8 original board also driving both z motos as parallel..

Is there a list which parts need support and which not?

There is a documentation inside the zip file.
For the carriages i will make one today

For option 2 with the extended z axis. You said 1 x Mgn12 360mm or 350mm rail. Which one should I get? What changes?

For the extended z axis its 400mm liner rail

Hey again Blv

Printing all pieces out atm, looks damn good!
Can't wait to assemble it all.

I'm a little confused by the whole extruder setup, and can't really find anything that works the way I want it too..
I want to use my stock extruder with a E3D V6 hotend as a direct drive.

From the groups on facebook I have talked with plenty of people who would love an option like that.. :)
Anything you would look into?

WOW! I am definitely trying this!!!! What a fantastic write-up! I suggest using CRC Brake-Clean for the removal of all the assembly stuff, I use brake-cleaner on like everything metal haha, nasty smelling and is strong and expensive sometimes but works SO WELL!!! It also pretty much evaporates off and leaves no real residue since it is made for automotive brakes that REALLY cannot afford to have a residue left on the friction surface. Worth every dollar in my book. I am going to see how this works:) Thank you.

Thank you bud :)
I hope it will be great, after you will finish I would love to see the results :-)

Where did you get the green wire sheathing?

Comments deleted.

You can find the full answer in the comments below :)

I read the comments below and searched for the suggested product. I searched high and low and cannot find anything that even slightly resembles what you have. My question was more of is there a specific link to follow rather than a name to search?

Silly question.

How many jigs are needed per rail? Do they stay on after assembly? So do I need 2 for the Y/Z axis or 4?

Hi :)
You need only 2 from each jig type.
Please remove the jig after assembly..

Do you have a link to the E3D V6 hotend you used? I see a lot of different options out there and I want to make sure I purchase one that fits properly.

Hi allen, i have used a clone one.
Its called V6 hotend (long version) 12v.
Link for such like product:

Also, the x carriage options are kind of confusing to me.. would be nice to see some details around what all I print to keep the original Anet A8 hotend/extruder vs what I would print if I upgraded to e3d v6/bowden.

To me it looks like there is the MK3 which works with the e3d, but what is the cube? Also I see the Anet a8 beta extruder adapter, but does it use the e3d x-carriage?

The MK3 is perefect for v6 bowden !
Personally i am using it and its the best.
Very very very reliable !


The MK3 and the Cube are both for the E3D. In theory, any of the knock offs will have the same dimensions. I have two genuine e3d's and I've had to teak the step file for tolerances.

The Anet A8 Beta extruder adapter is essentially a part for you to bolt the black U shaped plate that normally holds the extruder and nozzle of the A8 onto.

Hope this helps

Thank you friend :)

Hello, I am planning to building this and I have one small question. You say that we are going to need 7 x Mgn12H Carriage (4 for Y-axis, 1 for X-axis, 2 for Z axis). I am planning to do Option No. 2, and the instructions mention 4 x Mgn12 400mm rail and 1 x Mgn12 360mm or 350mm rail. That's total of 5, I am going to need 2 more? And what size?

I've built 3 of BLV like models (a lot of my own mods mostly to fit better 2020 I have). Now building one more.

  1. In first version only 300mm rails used for Y and Z, 400mm for X (220x320 table). Only one carriage on both Y rails and rails sit with some slide back and forth, so that there is enough length to full usage of 220 length of the table. It works! Only 4 of 300mm and one 400mm are enough for 220x320 table.
  2. Other models I built are for standard 220x220 table and I used 350mm rails for all axis and also only one carriage for each of Y rails. It also working well. Carriages are placed diagonally - one in rigth front and one in left back position.

For your question: 7 is the number of carriages and 5 is the number of rails, there are 2 carriages on each Y rail in original BLV model. I use only one carriage on Y rails.

Vapet.. I couldn't have said it better :)
Thank you

Hello I have reconstructed your printer, but I have 2 errors that I do not get in the handle, maybe you know that remedy.

1) I have strong Z-wobble, is there a fix?

2) And I have waves in the Y range, but unfortunately, I do not know where they come from, have already tried a lot but they do not get away.
(Motor swapped, drivers swapped, belts more and less tense, sled swap )

Hi :)
I don't think that Z-wobble is possible to have with mgn rails.
since x-axis and y-axis carriages are well constrained to the axis without any bending/lose.
The issue you are dealing with can be related to non consistent feeding rate / mechanical problem / setting issue.

Things you should check:

  • check that the mgn carriage glides smoothly without jams (oil the rails with lithium grease/ sewing machine oil)
  • check the Coupler and make sure they are fixed and not loose. personally i am using Aluminum non spring coupler 5X8.
  • check that all X-axis can be lifted easily and well leveled right/left equally.
  • do an Auto PID
  • Calibrate your E-steps (Very very very important !) especially if you are using bowden or changed your setup.
  • print a temperature tower to understand what is the best temp to work with your material
  • while printing check if the temp is stable or up and down.. this can cause a lot of troubles like this.
  • many many times banding effects caused by too strong fan. Try yo decrese you fan and see what happens. (Most of cases solving the banding effect)
  • Check your feedrate and lower your jerk and acc.
  • Check your slicer setting and make sure it suites your setup.
  • if you are using bowden, make sure that there is no gap betwween the v6 buttom and your teflon tube.

Send me a PM and i will glad to help you my friend :)

z wobble are definitely possible because the game between mother and threaded lockers, as well as moment loads of Mgn can not be recorded (according to technical data) and thus transmits to the X axis. Board is RAMPS 1.4 driver already tried several A4988 DVR8815 TMC2130) Temperature can not be 100% the waves are only in the Y axis not in the X also I print the same filament as before the conversion (PLA with 190 degrees). Jerk and Acceleration I've already tried all sorts of combinations of 1-20 in jerk range and acceleration of the 100-1000. many thanks for your help maybe you have other options what it could be. I use E3D V6. e Steps are calibrated correctly

I'm still building my version of this mod, but on my original anet a8 I had this exact same problem. it was a loose set screw on the Y motor pulley! I had to replace the set screw and pulley because they wouldn't stay tight.

Wait, your are not supposed to have too much play with the threaded rods and the T8-constrainer.
Also your not supposed to have any free play with the mgn carriage with a 3d printer loads.
Edit: saw your pm :) :) :)

An example how important to do an Auto PID and set the correct fan speed.
Image attached (one of the community member)

Comments deleted.

I’m seriously considering this upgrade. More silent, faster prints without reopardizing prints, practically completely eliminates z banding. Is there even a downside?!

Until now i am trying to find a downside..
Its only frustrating to see it running so well without the constant need to upgrade it :)

Comments deleted.

Hi BLV, I'm recreating the assembly of this printer in Inventor to make sure I will have all the necessary (fastening) parts when I make this printer. I noticed two things.

  • The first: some printed components have notches to align them with the aluminium extrusions. However, these notches will prevent the T-nuts to become perfectly flush with the inside of the aluminium profiles. The T-nuts have notches themselves and will compete with the same real-estate. I fixed this problem in these parts by removing a small piece of the notches in the printed parts (4mm in both directions measured from the center of the holes).
    I designed them for these nuts: https://nl.aliexpress.com/item/50pcs-lot-M3-T-Nut-20-M3-Hammer-Head-Block-Nuts-for-2020-Serie-Aluminum-Profile/32814359094.html

  • The second: I noticed that the holes of the Z-motor mounts and the Z-holder don't perfectly line up; only by fraction: 0.1mm (see added image). It appears that the distance of the Z-holder hole to the side of the 2020 profile is 7.9mm. If it were 8.0mm it would perfectly line up.
    Was there a specific reason for this? Or just a small mistake?

And some feedback for people (planning on) using alu extrusions from DOLD-mechatronik: you will need to use M6 screws to connect parts to the end holes of the profiles, instead of M5. This wil mean that some parts will have to be slightly redesigned, like for example a countersunk hole in the X-motor mount. A normal M6 screw would collide with the X-axis motor, so a countersunk bolt is needed.

Hi Martin :)

  1. The notches are there because there are a few types of aluminium profile, most of them do need the notches. You can definitely take them out with CAD or physically remove it, but most of the extrusions will need those notches.
  2. You are right, there is a very micro safety distance between the Z-holder mount and the extrusion, But i took that into account when i designed the other parts and its should be 100% lined up with the Z motor, other parts and the extrusions. Also please notice that there are more safety gaps with many parts. This method is reliably calculated in order to release material stress pressure. (After many many hours of strength simulations on Fusion360).
  3. The Hole for the button screw inside the X-axis motor mount is missing because the motor is far enough from the wall and the screw head not supposed to touch it. i choose not to make a hole in order to prevent weaken the X-motor mount structure. Also, keep in mind that the X-motor tend to work a lot and get hot, therefore i prefer to keep it away from the mount.
  4. Using other materials with different dimensions will need size adjustments and maybe even re-designing.

First of all, nice Job! Thanks
Could I use the original Linear rods on you're mod? Or they are they to short?
My expectation is to upgrade later to mgn12, but I have to split the costs.

Thank you :)
If you are talking about the threaded rods- so yes. You can use the original threaded rods.
If you meant to do only one axis - it is possible. Just use the original AM8 plans/parts for the axis you plan to keep with smooth rods.

Impressive job !! thxs

Thank you Simon :-)
Hope it will be helpful for you.

Hi! Nice design I have 3030 extrusion is it possible to assemble these parts on 3030? If possible reply.

Hi amjad :)
I'm afraid it will not suit for 3030 extrusion.
However i published the source STEP file and you can adjust it to 3030 with basic CAD knowledge.
I am Strongly recommend to use Fusion360 software.

hi, I wonder if you can make a tutorial to instal that full graphics lcd, I have the original A8 board and I can´t use my 12864 screen, please help

Do you have the discount reprap full graphic lcd?
It should be written on the lcd pcb.

Yes, that one

LCD 12864 RepRap Discount Anet A8 Adapter
by OderWat

I just want to say thank you for this awesome design!
After 3 months of ordering parts and putting them together I'm finally done assembling!
It's printing amazing!!! :)

I really appreciate that.. and i mean that.
So glad to see that all of the hours spent on this project helped this awesome community members.
My friend, i will appreciate if you could please upload some photos of it under "i made one" section :-)

I will when all parts arrived and the printer looks awesome :)

Thank you my friend :)

Just a heads up for people wanting to buy the alu-profiles from dold-mechatronik.de:
The M5x10 screws are too long and won't fit in their profiles when fastening their corner brackets. Use M5x8 instead!

Or you can add a Shim

hi, and realy great job!
i'm assembling this printer atm. and i ran into a problem with the e3d bltouch carriage.
i can't realy figure out how to attach the screws holding the belt on the carriage? i see 2 small holes (None of the 4 mgn holes), but no thread that the screws can screw in to? how do you tighten the belt/screws to the carriage?

ty very much! appreciate the work you did here!

I added these two notches for countersunk m3 nuts for now. seems to work :)

Hi, and Thank you :-)
The 2 holes made for 2 screws for the belts (check the video and schematics), just don't forget to add the top locker belt holder.
The reason i didn't added a place for 2 nuts is because the notches decreased the strength of the X carriage (fusion360 force simulation it failed). The top locker belt holder that keeps the screws together on top of the belt increasing the screws strength by 250% :)

Is it a problem to put on,T10x2 Threaded Rod Trapezoidal ACME Lead Screw whit Brass Nut,
because of the strength

I don't think it will fit, it was made for the most common Threaded Rod Trapezoidal. However you do have the STEP file
and you can make your on adjustments to the file :)

Is there a reason for the MGN12H carriages? Like height clearance or?

Because I have a mounting plate that fits the MGN12H carriages perfectly :)

I used mgn12H It because it is more capable of high load and wight.

Ahh I meant the adapters on top of the carriages :)

You can use your own adapters without any problem :-)

But do I need the adapters if I can mount the carriage plate directly on top of the MGN12H?

Thank you really much. Do you have possible measurements of the bed?

HI :)
The Anet Bed is 220mm X 220mm and a few comments below i added a pdf with the bed measurements.
Search for pdf file at the comments.

Hey Guys,
Blv that's truely awesome! Do you have the software parameters for me? So the offset for the bed and so on (Extruder offset..)

I made for you a PDF with all Offset measurements.
The bed depends with your build.

Does this work with the CR-10

Basically you can add it to your CR-10. Just make sure to make size adjustments.

Concerning Creality CR-10, after analysing each part of your mgn12 mod, the 2 big modifications would be made for the left and right Z mount motor.
No support 2040 profile on lateral side of motor existed on CR-10.
New support 2040 for cr-10 would be fixed underneath.the nema motor. Correct ?

May someone add or adapt these Z mounts for CR-10 ? i have no 3d skill design to make this modification, Sorry.


In my case i have a ratrig AM8 Kit (black)

so i think i need:

2 x 2040 extrusion 340mm (y-axis)
2 x Mgn12 380mm rail (y-axis) so i have to buy the 400mm ?
1 x 2020 extrusion 420mm for (x-axis)
1 x Mgn12 350mm rail (x-axis) dunno how long because its confusing me. List says 350mm but in the pdf it says 360mm
2 x Mgn12 350mm rail (z-axis)
7 x Mgn12H Carriage

Is this correct ?

Hey BLV,

Did you Y carriage's get rougher gliding when the carriage plate was tightened? I can't seem to tighten the M4 screws without impacting smoothness of the glide.

Lossen the screws and all glide really smooth. Anyways wondering if you ran into this issue.

Hi marceba
I have mentioned it before, you can tight screw the front carriages but the rear carriages doesn't have to be tighten.

Hiya BLV.
Thank you for the awesome upgrade.
I am wishing to do this but having some problems with the BOM list.
Some things I can not get my head around as to what they are. My Google fu is a bit pants on some items (like the M5X10 Button Head Socket Cap Screw "Google and amazon show different types"). But (I know I am a pain) would it be possible to ether get a link to each item or a picture as to what the item/s are. In the description.
Again thank you.

Hey these are the M5x10 Screws you have to use:
Ask again if you need more informations about other thigns from the BOM

Awesome thank you.
I was not sure if it was them or these :- https://www.ebay.co.uk/itm/SOCKET-CAP-SCREWS-A2-STAINLESS-STEEL-ALLEN-KEY-BOLTS-M4-M5-M6-M8-M10-/150846401601
And yeah i will ask again (which is most likely haha) if i come to a problem i can not google my way out off. :)

Once again, great job and thank you for your support during this journey of creating a new printer.
I'd like to modify this printer a bit :)
My intention is to cover the aluminum extruder (the base) by an aluminum sheet (1mm thick) to give it a nice finish.
The sheet will be fixed between the extrusion and the mgn rails and fixed also all around with screws.
The picture attached will explain better than my speech (and poor english).
To do this, I need to change the Y motor orientation from horizontal to vertical.
I took the X motor holder as it fit pretty well and modified it (I removed the tail) so I can put against the aluminum.
However, my skills in modifying object are very limited and I can't create the holes for the screws ( I spent hours without success).
I use Freecad, maybe it's not the right software to do this.
Do you mind to help me by making these holes?
The top of the holder must be at the same level than the extrusion.

Thank you for your help.

Hi Lanktus
Of course, I would be very happy to help you.
Please export your model to STEP file, upload it and i will add the holes you need :-)

I don't have any STEP file.
I just took your STL file X_motor_holder and I tried to modify it (removing the tail to have a flat back and trying to adding holes).

Looks like I'm doing it the wrong way.

Yes, The most optimal way is to open the STEP file that you can find in this project with Fusion3D app (very simply and user friendly CAD app).
Then you will have the most accurate file to work with and with simple tools you will be able to do whatever you want.
I can add those holes for you but i don't know how much space you need between the motor shaft end and the bed. Also please notice the the 2040 extrusion height is 40mm which means you have only 40mm for the motor and its not enough height, unless you are using and extended version?

Thank you for the advice, I'm going to dwl Fusion3D right now.
I don't want to change the size of the holder, the motor's base is below the chassis as I am using feet.
The top of the motor holder is at the same level than the extrusion.

First of all - nice work. I've upgraded to a 320 X 220 mm bed on my AM8 and am having lots of issues with the guide rails and this should be the solution. So thanks for all the fantastic work and videos.

My question is - the stock ANET A8 blower fan is a 5015 not a 5010 (an odd size). Can you confirm what fan you designed around - just want to make sure as I will buy a 5010 if needed, but none that I've seen look like what you have.

Thanks Craig for bringing this to my attention !
The fan i used is the original Anet a8 5015 fan.
added a notice at the installation text
I appreciate your comment :-)

You should design a direct feed bowden extruder (with bl touch) to fit onto this rail upgrade. Im hesitant to attempt this upgrade because the bowden tubing makes it extremely difficult if not impossible to print in flexible plastics...

Hi, i am working on it :)
I have designed a prototype and i am wating for the Titan extruder to arrive.
After i will make sure it works well, it will be released :)

Comments deleted.

Hi .Im ned bigger printing place like 400x400 .What im must change on this project ?

I have answered it before in the comments below.

Looked around but couldn't find any information regarding the Y carriage adapters you made.

Think about ordering a new Y carriage:

Will those hole dimensions work out of the box for these adapters? :)

Are you talking about the dimensions of the Anet Y carriage?
If so i can upload a simple sketch of the adapters proportions

Yea, just wanted to know if the holes in the carriage would match with your adapters for the MGN12H.

Ok :)
I made a sketch with the requested dimensions (attached)
The 20mmX20mm is for the mgn12 carriage and the second set of holes is for the Y-carriage

Hy there...cool design, in fact I've decided to build this one, in all black 2040...I will build the 500 mm Z version and I need to ask you the changes that I have to do in skynet...I need some numbers I think. ..can you help me?...

Thanks a lot for your mod...

You will have to increase the Z height on marlin

You did an amazing job !
I'm currently building one and I have a questions :

  • Could please tell why the hole over the X motor cover is for?

Do you mind to design a MK3_V6_hugger for a 40mm fan (30mm fan are too noisy)? I tried by myself and I definitely have no skill in this...
Thank you and once again, GREAT JOB !!!

Hi, Thank you :-)

  • As you can see at the posted pictures the hole is actually more like a channel to hold a 12-10mm PVC pipe that contains the cables.
  • You can try using a 40mm fan adapter of it (many adapters available at thingiverse)

On a couple of your pictures / renders and in one of the videos you have a green piece on top of the blue x motor part that looks to route wires, but I cannot find that stl in your files. Is that available anywhere?

You can find it in the files,
The name of the part is "X-motor_cover.stl".

This is amazing! I'm slowly assembling my own. I was wondering how to use the "Anet Extruder adapeter Beta". It's unclear how to attach the belt. I see two small holes (not the mgn12h ones) and was wondering if there was a part that supposed to screw there to fasten the belt. Should I just "ziptie it on" or is there something better?

Hi, thank you !
secure it with help of 2 zip tie each side and on top of the two screw install the x-belt holder which secure both screw heads.
I prefer the zip tie option other then the fixed adapters

Здравствуйте, это полноценный проект принтера или доработка?
смогу ли я по этому чертежу сделать принтер?
зарание спасибо)

The STEP file contain all the parts needed.
You can also find the basic manual at AM8 thingiverse page.

Hello guys, I was thinking about making this "improvement" to my machine.

In addition, as I´m fully disasembling it, I want to increment my printing size with a bigger bed (300x300mm).

However I can´t find in any store the bed platform. I did found this ( http://store.thingibox.com/es/laser/206-base_300x300mm.html#/tipo-metacrilato_8mm_negro ), but it is made with 8mm methacrylate and it is heavy for my 200x200mm version so this one must be so much heavier... And one more thing, it fits linear rail rods, not lineal guides as this printer or 2020 aluminium profiles for the other printers as Creality, Tevo...

So if anyone knows where I can find it I would really appreciate if I can have those links :)

You have to update pdf with part to rpint abs and pla and suggestion settings :D

The blue parts are PETG/Abs and the green ones are pla :)
But he also included one file with print instructions

not about new pieces... ;)

Would you be willing to add a E3D Titan Aero Carriage for this, or would the v6 one be compatible at all? I was hoping to upgrade to one of those when I do this conversion.

Right now i am working on a Titan direct drive carriage, as for the titan aero - it depends how well the titan carriage will preform.

Hey and congratulations for this nice mod!

I'm atm planing to build one, i have here a 220x270 Heatbed, i want to go with the 270 site on X, so the bed travels on Y still the same way.

Is my planing right, that when i change the 3 x 2040 extrusion 313mm to 363 and the X extrusion + rail 50mm more, than im fine?


Its seems to be just fine..
Wish you enjoy building it :)

Hello, where have you buy the rubber feet, please ? They look great !

i printed cyclops carriage mount but not fit my
could you make a version for this?
maybe a mod of your chimera carriage like this in picture whit space large 30mm and more long the support

whats the best material to make these parts out of?

will PLA work for any of them?

The best ideal material is Petg.
However some parts can be made from PLA. Inside the zip file of this design you will find a PDF with full
description how to print those parts. You will find there full info such as: Material to use with each part, infill percentage and so on..

Love the design! Rails are getting flown in from China already!

One small question would hate to go away from my direct drive.
Are you looking at creating a direct drive mount or did someone else already make some? :)

Great work!

Yes, I will start working on this soon..
First i want to upload a new updated 2-3 versions of the carriage and some other improvements (very very soon).
Personally i am considering adding a Titan Aero.

What are you using for those wire wraps?? I like them a lot

Hi :)
i have wrote it couple of time before, Its "PVC Flexible Corrugated Cable Protection Pipe".

I was wondering the same thing. It is also called wire loom. Below are some links I found . Not as cool looking as BLV's, but colors are available and it is another cool option if you don;t want to print cable chains.


If anyone is interested, I have added BLV mod support to my modular x-carriage design: https://www.thingiverse.com/thing:2599692

Modular X-carriage for ANET A8 / AM8 / BLV

Nice !!! great work !!

WOW all black..
I see you have made a custom plate - its seems to be very solid and rigid. Nice!

Thanks! All black petg.


My own design. Will update the thing with BLV adapter mount after some integration. I already see a few things that need fixing.

Modular X-carriage for ANET A8 / AM8 / BLV

Extremely Modular :-)

what are
I cant find in pdf

Those are new parts that designed after i made the pdf.

Feet - Small feet that you can add to extrusions corners. it has a hole for the AM8 rubber feet.

LED clip - if you want to add led strip, although you can just slide the led strip inside the extrusion without problem.

X-motor cover - its a cover for the x-axis motor. It will protect the 16t wheel and belt. You can add a P.V.C flexible pipe to hold all of the electronics. (Check my photos of the printer i built).

This week i hope to add a big update (more carriages and options) and refresh all the pdf.

hello Blv, i am in the process of making this awesome mod, i was wondering a few things. Did you see au real ( like a huge ) improvement in quality of prints and noise ?

And the second question, and its not 100% related to your mod but, if i want to make the bed bigger, can i reuse the stock board of my anet a8 and just change de configuration file ?

Anyway, this is a huge work, you a monster thank you very much for sharing this.

EDIT : i forgot, i want the bed 200*300, i already ordered my mgn rail and they are all 400mm long. I think it will be alright. For the aluminium extrusion, i just need to add 100mm on all the X axis ? Thank for you help !

hello, I copied it as far as all goes well, do not get the configuration.h,
they have a ready configuration.h for Ramps 1.4 mega2560.

Thank you very much

x motor mount dont need support for small part go outside?

Yes, you will need a support for this part :)

it's the only one? becouse i read nothing in the project about it :(

You are right.
unfortunately, with thingiverse platform i'm unable to choose what part requiter support and which one doesn't. But i am thinking on making a new PDF that will include this information. However until then, if you see a part with a hanging section, just add a support and i promise to work on a new PDF after i will finish the new carriages testing
Thank you

Printed tonight for test the xmotor mount in ABS with this settings (S3D)
15line brim
80mm/s speed
and obvisiouly... support
seems ok

good morning, congratulations for the project. I'm building a printer like yours, but I can not read the measures in this file because the photo is too small, could you enlarge the photo to make it readable? thank you

Hi and thank you :-)

The dimensions PDF file can be found inside the Zip file (not an image format but PDF).
Also please notice that the space between the bottom and the Z motors mount depends with your height of you coupler. With my printer i placed the Z motor mounts very close to bottom of the extrusions.

ok, thank you, I did not see it, now I can continue with the assembly

Hi Blv.

One question,
i am wondering, how did you fix the rails to the extrusion profiles?

With the standard square nuts?


Hi :-)
With an M3 T-nut / T hammer nuts.

hello what are these green hoses and where can I get them?

I have wrote it a few comments below:
"...pipe called: "PVC Flexible Corrugated Cable Protection Pipe".
the only problem is that it usually sold in 1000m rolls for contraction.
I found mine while walking down the street and saw a hookah store.
apparently, its pretty common to use those pips as a hookah smoking pipe. the seller was pretty sure i am crazy,
after i told him i could use a hookah pipes for my 3d printer.."

I bought mgn12 rail to make your project little be bigger... 30x30cm bed... but i cant find a way to how clean it in youtube :(
did you changed the steel balls? becouse the only video you linked is to do that... (which is the right diameter of balls ??)

Hi :)
I have not changed the steel balls, just cleaned them with a de-greaser (WD-40) and oiled them with sewing machine oil.
just be careful not to lose the steel balls! use a container to disassemble it so you will not lose them.
I have found a good video demonstrating how to clean the mgn carriages (i am NOT speaking Russian, but the video is very good and can be helpful).
Video: https://www.youtube.com/watch?v=luonzoH-xwQ

Awesome design my friend! I have everything but the rails which should be here today. One question... looks like you printed your cable management 'springs'? I love those things, but I can't seem to find a link for them.

Thank you :-)
Actually It's not a printed spring but a pipe called: "PVC Flexible Corrugated Cable Protection Pipe".
the only problem is that it usually sold in 1000m rolls for contraction.
I found mine while walking down the street and saw a hookah store.
apparently, its pretty common to use those pips as a hookah smoking pipe. the seller was pretty sure i am crazy,
after i told him i could use a hookah pipes for my 3d printer..

Da pra usar mgn300mm no eixo x?

I'm afraid 300mm is a bit smaller than needed.

I almost have all the hardware! Just waiting on the rails!

I'm having trouble printing the y carriage adapters. Two of the hex bolt holes are printing without a wall leaving it open.

I think it's because it's counting the text on the side in the walls but despite reslicing, no dice.

What slicer do you use and how many walls are you printing?

jpg is a picture of the carriage adapter

I am using Simplify3d and 3 layers walls for the Y-axis adapters and it closing the adapter walls. (actually, i am using 3 walls for all the parts that needs to be extra strong)
However, You can use it without the external wall, the nut hole are there just to hold the nut locked.
Please don't forget to scrap out the hanging material (the curly petg leftover in the nut hole), the nut hole should be flat, else the nut will stick out and it will not be straight.

Thanks for the heads up. I'm still struggling with the petg and I'll most likely reprint these. If you have a moment, would you be willing to slice one and post the g code just so that I can make sure it is the slicer? I'm looking for an excuse to buy a s3d anyway.

Problem solved, Check out the new improved adapters (thing updated) :)
I tried to slice it with cura and saw the problem. Any way, i moved the text to the other side and made the outer wall 1mm thicker.
Now, you will not have any problem to slice it and get a perfect adapter :)



Hi, first of all, really cool design, kudos!
I've been using the standard AM8 for some months now with genuine e3d v6, marlin firmware and my own x-carriage design but got a bit bored with it. Everything works great and constant fiddling/upgrading stopped.
I was thinking of buying original Prusa mk3 until I saw your little monster. So instead, I ordered the linear guides, additional profiles and can't wait to get rid of cheap Chinese 8mm rods and start building!

I think I'm addicted to these printers. I haven't even finished crafting my first AM8, and I've already ordered parts for this mod so I build a second one!

I've had to shift to a capacitive sensor for autoleveling due to the inductive sensor having a hard time seeing aluminum through 4mm of glass. Once I get that dialed in on my original A8, I'll finish and setup the AM8 to print the parts for the BLV mod.

And Rover31 beat me too the punch. I want to build a 400 X 400 based printer next, hopefully based on the BLV design!

Great design though. I look forward to building it. I'm thinking of designing a carrier for the E3D v6 that has all the mounts for the autolevel sensor, cooling fans, etc., unless one of you has already done it?

Thank you :)
Glad to tell you my friend, that I'm close to release a new carriage locker which allow you to use
Mistral fan, Semi circle fan and full circle fan. along with an adjustable bl-touch/proximity sensor (8mm/12mm) holder :-)
meanwhile skip printing carriage and the locker (on the next couple of days i will upload a new updated version)
I will update you after i will finish..

"Mistral 2.1" Extruder Cooling Duct for the Anet A8 Printer
by Leo_N
Semi-Circular Anet A8 Fan Duct
by lokster
Hesine M-505, Anet A8 - Center Nozzle Fan
by Arjjck

great design and idea. I am deff leaning this direction!
So how do you think it would be to incorporate a larger build into your design? Something such as this,

Thanks for your thoughts!

AM8 Large Print Volume 220x320x290 (Enlarged Bed)
by thaug29

Thanks :)

Since it a modular design - No doubt..
Only you will have to get a bigger rails for axis's and bigger extrusion for the x-axis.

May you include a direct driven e3d titan x carriage mount? :)

dude that thing looks so sick. major props to you

Thank you my friend !

How important are the screw head types? Are there any specific spots where a button head could not be used in place of a hex head? Or vice versa?


The head cup goes for the Z motor mounts and you can see the the exact location at the
AM8 manual - its wrote inside the AM8 manual

AM8 - Metal Frame for Anet A8

From the looks of things, the original printer was basically a source of hardware (extrusions, belts, PSU, electronics. Do you see any reason why this printer could not be assembled from scratch? In other words, was anything you used out of the A8 custom and unique to the A8? Thanks.

Well, you are absolutely right !
Basically, you are totally right. you can take your own hardware and fix it into this design :-)
The only things that should be the same is: 16 teeth idler, check if bed carriage fits and standard nema stepper motor with same size as the anet a8 motors.

Now that is perfect. That just means I can move forward because I have a ton of parts here! Thank you.

Extrusions and rails ordered... Should probably start printing stuff at some point.

Nice !
Have fun building it :)
it takes a lot of patience with the carriage cleaning process but it worth it.
The precision and print quality is definitely noticeable !

Hey Blv,

Your TR8 nuts do they have springs? Mine came with spring and be damned if i came just get the nut in let alone the spring too.

Yes, my TR8 came with anti backlash parts (spring and another small part).
In my case the anti backlash kept jamming the Z-axis. I took it out and
I like the results.

Since installing the rails might be tricky, I wonder if a 3d printed alignment jig would be helpful...? Totally looking forward to 0 wobble on my Anet. Thanks BLV.

Update: added 2 types of Jigs for 2040 and 2040 :-)
Thank you mate !

Awesome. Cheers

Yes, you are totally right.
I will add a jig :-)

hi, that's a great project.
I have printed all the parts and start building now

whar fan duct you have mount?

can you give us a link for it?

Nice !
I have used the radial fang fan from here:
Notice that you need to get from there the stl for 5015 fan.

Radial Fan Fang
by Lion4H

Hello what is the space who seperate the front and the back block, please ?

Hi tull :)

The space between the Back of rear extrusion and back of Z extrusion is: 119mm
inside the Zip file you can find dimensions.pdf file that contain all the dimension.
Please notice that i need to fix one error there: the Z motor mount should be pushed down until it will touch the Bottom_Tee_Plate

119mm behind adapter front and rear, i ask that, it's to adapt it for my 300*300 bed mount support, thanks.

i'm doing the same, which size you used for X and Y extrusion profile 2040?

Hello, I added + 80mm because the original heating plate is 220mm and the one I put is 300mm.

I found printing the z motor mounts caused it to warp for some reason using PETg. Couldn't get it to print successfully so i sliced with 4 perimeters and 20% fill and these guys are solid as a rock. Not sure if 80% fill is needed. Takes like almost 6 hours to print each one but they are almost done now.

Hi marcbea
If i am not wrong, Petg should not warp unless it has high humidity percentage.
Any way i hope that the 20% will work and 4 external walls will increase the rigidity of the part too.
I would appreciate if you could please share your work after it will be finished :)
Thank you :)

Yeah brand new roll just opened it. Filament box is at 30% humidity so should be fine. Yeah the part i did print is super rigid and fits perfect on the extrusion. Was so amazed last night when it started to bridge on the reinforcement parts for the z motor mounts. Not a sag on almost an inch distance. :)

What are your print settings, retraction distance and speed? I just ordered petg and I'd love to have a baseline to start from!

Here are the details

Print speeds and quality:

0.2mm @ 40mm/s
5mm brim
20% infill
4 walls
Top layer 2 Bottom 2


4.5mm @ 60mm/s


Hotend 235c
Bed 55C

Touch of hairspray on the glass bed does a great job if you have your leveling tuned. Print on of the x holders first to check your dimensions and hold sizing to make sure you don't have to tweak your printer first before doing hours of printing. Forgot some details above so added brim infill and walls

That sounds like hard learned experience. Thanks for the heads up

Once again, thanks Blv.

Getting closer to my next upgrade for my Ranita AM8 https://www.thingiverse.com/thing:2462104 , as the MGN12 rails with MGN12H carriage arrived from Aliexpress. I bought them on their 11.11 sale

2x 400mm https://www.aliexpress.com/item/12mm-Linear-Guide-MGN12-L-400mm-linear-rail-way-MGN12C-or-MGN12H-Long-linear-carriage-for/32837995749.html?spm=a2g0s.9042311.0.0.ASiIHB

3x 350mm https://www.aliexpress.com/item/12mm-Linear-Guide-MGN12-L-350mm-linear-rail-way-MGN12C-or-MGN12H-Long-linear-carriage-for/32838019510.html?spm=a2g0s.9042311.0.0.ASiIHB

All rails where well padded, sealed in plastic, covered in machine oil. ~ $78 shipped for 5 rails.

Slowly printing out parts...

Anet AM8 Variant
by ranita

Have you unpacked and inspected your rails yet? I'm ready to pull the trigger, but the seller has subpar reviews (only 15 reviews total) and one complaint specifically about the rails.

Agreed with blv, they will need cleaning.

I have only unpacked one of the rails to inspect and it seems fine. I inspected the others through the plastic and they seem fine too, no wobble due to missing balls etc. I am not an expert, but it slides smooth despite all the packing oil.

Thank you very much!

Did you get them to combine shipping? It's looking like $86 total right now. Oh, and I think his price went up a dollar from earlier today.

WOW ! this is actually a very good price !

It looks like all 5 axis plus two additional carriages will run about $100USD shipped. Not sure how Artistebot pulled off $48.

Nice !!
Don't forget to clean the mgn12 carriage carefully. dissemble them inside a plastic container so you would not lose the steel balls.
I have found a good video demonstrating how to clean the mgn carriages (i am not speaking Russian, but the video is very good and can be helpful).
After you will finish i would love to see your creation :)


Some people have used HBLFSDW5 brackets which connect to both slots instead of just one.


Have you found any instability related to only having the bracket in one of the two slots? The above 20x40 brackets are $3.50 each. I would rather forgo them entirely or at most, just double up the single brackets.

Hi KarmE,
Actually the one slot brackets are quite good. For the Z extrusion you can use the double brackets and it will hold even better.
Notice the inside (for the extrusion below the Y-axis mgn rails you will have to use short/one slot brackets).

First of all, wow, thank you. You brought some serious game to the AM8. Thank you.

Question about the Y Axis extrusions. Pheneey uses 340mm and you have 364mm.

Am I overlooking something?

Thanks again for your contribution!

This Question was already asked (And I just discovered) by user Mycroftholmes on Oct. 22 and subsequently already answered by BLV. To save some scrolling, the short answer is Pheneey's design shorted the bed from the original Anet, and BLV's extrusions restore that loss. I'll delete this comment if people think it junks up the board or if I misinterpreted the answer given

Thank you my friend !
Please don't delete it, i think it can help others.

Good luck building it :-)

Comments deleted.

I realy like your Modification and want to rebuild it. I have only one Problem with the Mesures , because i got a Coocheer A8 with a 220x270 mm bed and 270 mm height print volume.
4 x 2040 extrusion 364mm (Y-axis) i will change to 4 x 2040 extrusion 414mm (Y-axis), because my print bed is longer than a usual at a anet A8?
I would be thankfull for help, to step on with that nice Build without cut or order wrong mesured profile parts.
Height will be ok, usual i can upgrade the linear rods later.

Theoretically it depends on the bed carriage more then the bed. I can try mesure it to see if you will need a 450mm mgn rails
Do you have any sketch and domension of the bed carriage

The H carriage of my Coocheer A8 + is 21,5 cm Long and 22 cm Wide. Plus my justation Screws lets say 23 x 23 cm.

Oh i am sorry for the delay
saw it only now, i will try to simulate the carriage and tell you :-)

So i need to try on good luck now, or could you say please if your 22cmx 22 cm AM 8 has the same 22cm H carriage too, in both directions?
My A+ heatbed overlaps the Ends 2,5 cm up and downside. Maybe i need to give it a try and hope for, not to knock against the frame.

No Problem, i where busy too. 23x23cm H carriage and 22x27cm bed. Height is 27cm, but i wil incease it up to 60, i think so.

I am not sure but i think the H carriage is the same like the normal 22x 22 cm heatbed Anet. Maybe i wil get problems with my extended Heatbed which is 5 cm longer than usual, thats why i ask for.

I think i found a sketch of it and looks the same, but i can't guarantee that because its very difficult to find the correct dimensions of it.
is saw at list 4 different dimensions for the same carriage.

My lead Rod for the heatbed is 44 cm long, does that fit ?

If i understand you correct, you are talking about the Y-axis movement. Then, You will have to get 450mm rails

Still having a Diamond hotend laying around which i plan to use with. Is there any chance that you could create a Diamond Hotend Holder or do i need to tweak them together myself? the diamond Hotend is 8 cm wide and needs a bit more space.

That MGN12 Rails hurts in the pocket. 4 pieces 80 euro :D goin on.

if i am correct i need 5 rails plus 7 Slider and not 7 whole rails with 1 slider ?
Urgs, maybe i need to cut one down to save Money.

Hi Felix
Only the 2 rails for the heated bed has 2 carriage.
Here is the List:
Z-axis (Highet): 2 rails + 2 carriages
X-Axis (left<>right): 1 rail + 1 carriage
Y-Axis (heated bed): 2 rails + 4 carriages

it works just fine with 3 carriages on the bed :P

I need to try it with 3 three carriages, too. One ordered Slider where Trash...

Yup, it will work well.
Two of my rear bed carriage less tighten and it working just fine

Done up to a working Mashine.
Make Nr 10 now. Gz
I changed the mesures to make the X Extrusion to fit 400 mm Rails.
My luck i did that, because the 450 mm Y Rail you told me was 4 cm to short for a Anet A8+ Bed. Solved it by placing the Bed sidewards and +40 mm to all Z extrusions in front of my Order.
Why such complicated? Maybe it will be wise to count screws on the Anet Basic and don`t neet to cut a 400mm Rail down to 360.

Respect and Honor for this Build.
I realy love it hundred times more than my old flimsy Anet A8+. Such quiet, like two times more noicleless as the old freaking Plexi Glass Anet A8 Mashine.
The Y Bracket for the nema 17 is easy changeable against a 2 Euro Nema 17 Frame Mount.

Well done my friend
Are you using the original A8 board?

And hell why name it prusa i3 clone? i3 is like 1879 and this Sytem with all the Rails is like 2024... :D
My prefered cheap upgrades for Z and Y stepper Motor Brackets are :
A realy cheap usefull full metal bracket. 2,50 Dollar per piece only and closely cheaper than printed Brackets.

Because The structure of the x/y/z axis is same as prusa i3 mendel.
Have you checked if the motor brackets is in the same distance?

Such a Pain with the MGN12H rails to get fitting Clone Slider. Realy recommented to buy two quallity Rails for the Heatbed.

This bracket is 2,5cm shorter than the Z motor brackets. I prefer to use that bracket at Z and support the frame with some corner brackets extra. the Height is adjustable by the long screw holes. the spindle carry is adjunstable at the X axis, so it will work.
For the Y Motor bracket i may need to support it with a long Plate and some spacers, otherwise it will be fit perfect but only bond to one T-Nut slit.

i think that the original H frame is totally bended trash and it would be usefull to order a new more precise Carriage to fixate the rails realy straight and beeing able to tighten all Srews at the Rails.

Can i find somewhere the Marlin Files for the specificated Displaysetup you still show on pictures and Videos?

Atm yes, but i willing to change it. For testing Reasons i will order a 32 Bit Board for my own security, before i try to upgrade the standard Board with Marlin.
Later i will test this setup with a Duet Wifi & Duex5 and a 5 in 1 out Prototype Hotend and a Prototype Saphir Nozzle.
Do you got instagram? Maybe lets sub us both and follow for further personal Upgrades.
User Name: Felix_Magnetix

Nearby all ordered Stuff did arrived. There is a good chance that i will be Number 8 in the 'i did build one' area at next weekend. :))))

So i bought One rail to much now. 4 x mgn 12 400 mm. In Need for the two Y Axis mgn Rails 450 mm longer in case of my extended Heatbed.
One 400 mm mgn I could cut down to 360 mm but I can't expand their length really well.

where in the USA are people getting the Mgn12H Carriages?

Comments deleted.

You can find mgn12 rails on amazon / aliexpress / ebay

So do I need 2 440mm extrusions even when not changeing size?

I just got my am8 frame and don't want to buy more extrusions unless nessesary I see you mention option 1 won't change size but still needs two extrusions in the bom

If you want to leave the original AM8, you just add two exteusion (on the Y-axis) for the y mgn rails + brackets. Rest of AM8 extrusions should be the same..

Comments deleted.

Nice, that's taken it to the next level.
thanks you

Thank you my friend !

Very Nice! I don't have the time right now, but if I'd upgrade my A8, I'd do it your way.
Kudos for releasing the step files!

Another 3D-Printer working with linear rails is the cetus. You might look at the belt-management which i really like!

Thanks Thorax :)
I admire the clean setup of the cetus printer !
At first, i designed a belt system running inside the aluminium extrusion, but after couple
of hours i noticed the belt was to close to the extrusion core. Knowing that bigger wheels
such as 20T decreases the accuracy - led me to design an open lifted belt system..

my friend that excellent work, I mounted an original am8 and wanted to replace with MGN only the X axis, but I see that its parts of the X axis are attached to the Z axis what solution?

Thank you mate :)
Since it is a modular design, you can try and use thaug29 2020 X-Axis 2020 mod.
Then try to add the X-axis parts from the mod i designed.

Anet A8/AM8 2020 X-Axis 2020 for E3D V6/Titan Aero
by thaug29

Entendi, obrigado!

Hello, for what groove you have make the parts 5 or 6 mm

All the parts that fixed to frame are 5mm (hole)
Some internal parts with m4 and m3 (not to the frame).
You can look for it at the am8 manual and the bom file.
As for the other m3 & m4 all the description its attached as pdf file.

Y Axis question: I currently have an AM8 and used the 364mm extrusions on the sides as per the AM8 variant. The two new 364mm extrusions are held in place by alum corner brackets?

Thank you

Yes, the two 364mm extrusions below the rails are held with corner brackets (two brackets each).

That's all I needed to know, thank you!

First of all: WOW, you put really much effort in this, not only for building it but also for documenting it well!
Thank you a lot for this, also for the hint on how to get the china mgn12 rails to properly work (will try that asap).
I want to build this from my own custom made prusa i3 and have recently ordered a mk42 bed, has anyone tried using it and will it fit and be usable in all its size?

Thank you :-)
The bed used in the project is 220X220, I dont think you will have problem using 250X210.
For 300mm bed: it will fit also but the hotend will not reach the edges unless X-axis size increased.

Whenever this thing is completed? I'm looking forward to it and i will definitely build one! <3 <3 <3
Thank you for build and share that with me and everyone!!!

I have built it already :-)
A few things left to do.. such as installing BLtouch, find center of bed, PID, calibrations and finding Best jerk / acc
Then i will post the results :)

Hi Blv,
You did a really great job here!!
And yes, a BLTouch would be really appreciated :)
In your file "BLV_mgn12_mod", green is for PLA and blue for ABS/PETG or it was just for the style?
Are pieces in STL files in the way they have to be printed?
thx :)

Thank you :)
The bltouch will be installed with fang fan (This fan has a built it sensor mount for bltouch and proximity).
You are right, all the parts colored green is for pla and blue for petg, but some parts can be changed according to user will.
I added now a few new parts:

  • new feet mount instead of the tapping method
  • led strip holder for top and x-axis
  • improved x-carriage

Right now i am working on adding higher version of mgn y-axis adapter.

Hi, thanks for this awesome piece of work. One question : In the BOM it says : 5 MGNH12H carriages but shouldn't that be 7 ? (4 for the bed, 1 for the X-axis and two for the Z-axis)
Thanks for clarifying !

Correct !
I thought i fixed it 3 days ago, but after saving i got "token invalid" on thingiverse site (too much edit time i guess)
any way i have corrected it now
Thank you very much body !!

Comments deleted.

Could you please advise the lengths for 2040 for the front, back and top of the printer. I could not see this on the BOM.

My friend
Its 313mm according to AM8 manual
as i wrote in section "Choose your Style" at the item description, first you will have to choose your style (Original AM8 OR extended Z height). then, since it's based on the AM8 you will have to download the AM8 manual from here.
i wrote. Dont forget to read the "what to print" section in order to know what to print from AM8 parts.

AM8 - Metal Frame for Anet A8

This is awesome, I am preparing to upgrade to AM8 soon.

Cool ;-)
It's a lot of work, but man.. what a difference !

Hello and thank you for sharing, I would have liked to know if a heatbed of 300x300 can be installed with the dimensions of the frame to 500mm?

Thanks :)
you will have to replace the 313mm (2040) extrusion and the X-axis (2020) extrusion.
if you will not do that, the V6 carriage will not cover the bed edges (Y-axis depends on the carriage size)

And on the y axis no change? I thought to extend 80mm both axes (frame and rails). The original bed is 220mm and the one I want adapted 300mm that's why 80mm.

It depends on the carriage you are going to use.
Give me a link to the bed carriage and i will calculate for you the Y rails/extrusion size :-)

I think I will cut a plate of aluminum 300 * 300 like the heated bed.

So will you leave the space between the mgn carriage the same?

I will use the mgn12h which will be fixed under the plate of aluminum then between the plate of aluminum and the heating bed, the springs and screws.

Yes, but before you need to calculate the Y rail length because the travel distance extended by 40mm each side.
The distance depends in the space between the carriage that holds the bed carriage. please tell me the space
between mgn carriage (rear<>front) then i will calculate what lenght of rail you will need for 300mm bed

In fact, I thought to take the distance proportional to that of the 220mm!

That makes sense :)

Oh yes! now here is a mod I like!


Thank you :-)

Thank you this is brilliant.
I do have a few simple questions though that being if i was wanting to do this build without making it larger and with using the standard extruder carriage what i the parts that would be needed? I have seen that you listed a Mgn12 350mm rail instead of the 400 for the standard build size am I just missing the other parts that would be needed?

PS get better need good designers out there...

Well ,i worked on something, check the attached images to this post.
The weight is still an issue and i'm afraid you will have to get a longer extrusion instead of the 313mm.
since the Original Anet extruder is very wide compering to V6 it will not cover the edges.
the adapter i made is only a prototype and i am not sure about it.. on Sunday i will be at home and check
again the measurements.

Thank you :)
you will need the 350mm rails, But for the extruder - i will have to make wight and size simulation of the original carriage.
if it will fit there, i will design a mgn12 carriage to Anet original extruder adapter .

I will update you :)

Honestly this is really stunning work that you have provided to the community. I wish you a speedy recovery. Many thanks for releasing the STEP files.

Dear friend
i really appreciate that, thank you :)

First, I hope you recover soon.

This is AWESOME, thanks for creating this. I recently completed the Ranita AM8 that turned out great. After I finish my MksGen1.4/Bowden upgrade might have to do this!

One suggestion.

The original AM8 LCD mount uses the Anet LCD, that when mounted on the front, would still fit within a Ikea "Lack Table" enclosure, mounting the 12864 will cause the AM8 frame to no longer fit (too long). I recommend the "AM8 RAMPS Full Graphic LCD Smart Controller Mount" by PapaJohn88.



Thank you mate !
I appreciate your excellent suggestion and will add your recommendation to item description.
also i am very pleased to know that my work can be helpful to you :-)

Thanks for the reply.

From the look of the images, your solution seems to be not any wider than the "stock" a8? The "other" v-rail,slot, open-rail etc A8 solutions seem to be wider, so they would not fit in a "Ikea Lack table" enclosure. BRAVO!

Why did you change the vertical (Z) 2040 extrusion to 500mm from 440mm? Since I have already built my AM8 frame with 440mm Z will it work with 350mm rails?

Thanks for the note on a source for the rails, as I thinking of buying the rails form Aliexpess "Cheaper the better" I was thinking but maybe not? One seller (wuhushiyu Store) says in their listing "NOTE: We can cut in any length of rail. Just do not hesitate to tell us your request."

PS: Found the "link cnc store" as they seem to be the only one that offers 360mm rail. The pictures show rails scratched and worn etc.

Thank you :)
I have changed it to 500mm in order to increase printing volume height
The main reason i am answering only now is because i made some simulations with a 440mm extrusion (original AM8 size).
at the end i found that 350mm mgn12 rails can fit there pretty good (measured it with a 350mm threaded rods).
Also, the drawing/sketch of the simulation attached to this