RapMan 3.x Corner Set
Description
They may be used as stronger replacements for the (very fragile) standard acrylic corners, and are designed to be installed without having to take the whole machine apart. Most corners now require only 3 easily-accessible bolts (down from 8), and importantly, no more fiddly grub screws :)
Apart from making the whole machine stronger, the Z motor corner now includes a mechanism to easily and accurately adjust the tension on the Z belt. This is now a one-handed operation, not three-handed!
The Y motor corner requires 2 files (top_backleft.stl, ymotor_clip.stl) whilst the Z motor corner requires 4 files (bottom_frontright_backleft.stl, zmotor_*.stl) All other corners are each 1 file only; even the top corners, as the bearing holders are now all integrated.
I have endurance-tested these parts with a 24-hour non-stop print and everything is still running smoothly. If I find any weaknesses, I will update the STLs.
NB: Some of the green STL auto-renders displayed left and below are mirrored; they are however correct once you download them (tested in both BFB Axon and MiniMagics)
Instructions
The vast majority of these parts are designed to be printed on almost any 3D FDM printer with no supports, using standard ABS and no heated beds or other fancy attachments. (Do not use PLA, it is too soft.) The parts in the photos were printed with a Rapman 3.1.1, using G-code generated by BFB Axon v1.11. After printing, I recommend cleaning out the holes with correspondingly-sized drill bits (3mm, 5mm, 8mm, 12mm)
Only the Y and Z motor corners require further detail here:
Y motor - Note #1: top_backleft.stl requires support to be printed. Simply use standard Axon settings but turn support on (I used cross-hatch 10% 'everywhere', perhaps 'exterior only' is better)
Y motor - Note #2: When fitting M5 bolts through ymotor_clip.stl, you only need to tighten the bolts until the gap closes to ~0.5mm (see photo)
Y motor - Note #3: The photos show a 3mm-thick arm holding the Y limit switch; this has been upgraded to 6mm-thick in the STL.
Z motor - Note #1: To attach the carriage to the plate, you will need a 70x8mm smooth rod from one of the top front corners, so print and replace those first.
Z motor - Note #2: The plate measures 122mm in its longest dimension at the base, so it will warp a little during printing. Don't worry about this as the warp works to our advantage once the Z motor is mounted to it.
Z motor - Note #3: I highly recommend replacing the Z pulley as the standard one is very fragile and either breaks or comes loose quickly. I used the design near the bottom of this page: bitsfrombytes.com/wiki/index.php?title=Spare_parts
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Hey Chylld
I'm a designer and have to say very nice work!
I have a Rapman 3.1, do you think that I could print in PLA? (as all I have atm). Would it still be OK but not have the longevity of ABS print? or just a no-no in general?
Thanks
Using 123D, it's possible to trace pictures. Like the ones in the Rapman assembly manual. The screenshots of their actual CAD drawings. I wonder if there are legal issues if we make the Rapman's original CAD files opensource...
Hi chylld, i see you recomend the Kisslicer, i dowloaded it and read the tutorial. Could you give me your best settings or normal settings, just to save time, is its too much diference in Presision%? Thanks you!!
Hi, I was just wondering if the fan function is part of your file for axon? I've printed some of your parts but the fan doesn't turn on usind bfb axon 2
Hi again, since your Z gear the machine has worked perfectly. I am finishing printing this set and i wanted to ask you for some advice or a plus instruction because i dont know where should i start assembling this parts. Like: should i start with the bottom parts? or the upper? all together? first disarm the whole machines corners?
I must tell you im 18 years old with no experience haha, sorry for my ignorance and i would be very usefull if you can answer this to me. Like always, thanks you very much!
Hi Chylld thanks a lot for this !! it's possible to have the source??
Hey Chylld
Great parts
I have 2 weeks my RAPMAN 3.2 and i like to make the corners
When i load the parts in AXON2 they are red and corrupt
can you help me please
Very good looking, I am considering one set of these to my RapMan 3.1
I just started to upgrade my RAPMAN 3.1.0 and found your parts are the answer to many questions. These are outstanding parts with a well thought out design. I am looking at the parts for the Z axis and am having a few questions on the assembly. I was wondering if any additional views were available. I would like to see the way the 4 pieces go together. Thanks for an excellent design.
A question that I would like to ask is what thickness do you recommend for the Z step? I made mine and the layer thickness of 0.125mm and was wondering what you would recommend?
Are you planning any additional parts improvements or is this a done project?
Thanks for the comments!
The Z corner goes together very easily, first install the corner bracket as normal. Then secure the 8mm rod into the large Z motor plate (see Z note #1 above) and fit it to the Rapman. Then assemble the Z carriage by first securing a long M3 bolt, then using the original M8 bolt through the Z wash
er and carriage pieces (no metal washers next to the bearing.) Then slide it on to the 8mm rod and tension with M3 nuts on the M3 bolt after it goes through the hole on the plate.
I always use 0.25mm, if I need very high quality I use 0.125mm but very rarely as it shows the Z wobble a lot more. The
next version of Rapman replacement parts will include anti-wobble bed holders and an entirely new design of extruder carriage :)
Hello chylld,
I just printed and installed one of your corners, TopFrontRight because of broken acrylic. It really looks fantastic in black, its a nice design and one day I might replace them all. I do have some comments though that might improve it a bit:
-The top which contains the bearing was bending slight
ly away from the rod , there was a gap of 1-2 mm. I drilled a hole and used a cable tie to get it firmly on the rod. It might be a good idea to have an extra screw here or just a hook that better grabs the rod
-My bars where slipping inside the corner, i had to add some tape but it was hard to find
the good amount of tape. Because everyone has a slightly different printer its hard to get the good fit and clearance. Maybe there is a better clamp system possible that more tightly grabs the bars?
-The top of this corner might need a bit of reinforcement to make it more rigid, there is still quit
some bending when you tension the belts.
-If I setup my Y carriage and want to make it perfectly parallel to the front of the machine I push it agains the front two corner blocks (as per manual) and tighten the grub screws of the X motor coupling and pulleys. This was possible because the two corne
r blocks had the same depth. Probably when you mount all your corners you have the same effect but I only mounted one and now I need to set it by eye. So maybe its good to design the corner so the depth is the same, and thus compatible, with the bfb corners. Its only 2mm extra.
et voila, thats all.
Thanks for the fantastic parts.
hi unfold,
thanks for the feedback, i will respond to each one in order:
1) yes this is likely to happen due to the design (my own one has a gap of about 0.5mm). for version 2 i will add a clamp at the top that also addresses point 3 below
2) i have a new clamp design in mind, it makes each corner more tha
n 1 part but will allow much more tightening without fear of breaking it :)
3) the new clamp i have in mind (from point 1 above) will thicken the top section, improving rigidity. mine have a slight amount of visible twist due to belt tension
4) i just measured the acrylic part as being 9.5mm from
the centre of the pulley bolt (holding the belt) to the rear edge (that touches the Y carriages). can you confirm?
Very nice work you have done here. I'm impressed with the strength and simplicity of design.
I have a group of Jr. High kids, a RapMan that the good folks at 3D systems gave us and a couple of high end PC's running SolidWorks (all donated).
Being able to show the kids (and their parents) some designs that apply to real world uses (like enhancing the RapMan) is a great teaching aid.
Wel
l done!
I also pretty like the design and the simplity of it.
However, I did the mistake, as I know now, to print these using PLA. PLA defenitely is too soft and fragile. Two pieces already broke. I also experienced that the rods sort of slip inside the pieces. Today I inserted some tape to increase friction and my test print seems to be working fine.
My advice would be to use ABS with maximum fill, inserte some plastic tape and possibly even increase the thickness of the pieces, where approriate of course.
But still, thanks for the design!
I assembled my RapMan using these pieces. I had to invert a couple of surfaces in netfab, which was no problem.
I did have a small issue with the "Z" idler alignment...the belt would ride up towards the upper flange when moving in the -Z direction. I eliminated most of the problem by slipping one of the unused corner platform springs over the belt tensioner rod before assembly. The other thing I found to be important was running with a very low tension on the "Z" belt.
One small Question......why didn't you include a hole in the Zmotor washer?
holy $#!
&
amp; what a mistake! i remember making a quick adjustment to the bevel angle just before uploading but i guess i forgot to recut the hole... i'll fix it tonight!
(why this has been downloaded 142 times without being pointed out before?? maybe everyone has drills at home...)
Querstion: Did you have to purchase any additional bolts/nuts that were not already in the original parts? I'm thinking about putting your information in a instructional format to be given to schools and wanted to know if they needed to purchase any additional parts. Of course all design credit would be given to you.
Thanks
Love the mug shot.
Sorry for the late reply! Didn't get any notification.
These parts are designed to use the bolts that are used in the old corners. No additional purchases are necessary.
The only prerequisite is for the Z motor corner - you need to replace one of the top front corners first as you need a 70x8mm smooth rod for the Z tensioner carriage.
Great Job!! I'm excited to share this info with other RapMan USA kit builders. This would be a great classroom activity for schools building the kit.
Thanks for your time and commitment.
I printed the top front right corner unit in 2:15 and installed it in about 30 minutes from start to finish. It works perfectly.
http://technocraticanarchist.b...
Good job!
Wow, this simplifies the RapMan build so much. How long did it take you to reassemble everything?
I can only remember the time taken for the Y corner is that is what I did last. It took about an hour to remove the old parts and about 5 minutes to attach the new :)
If replacing all the corners at once, I'd estimate a few hours to wrestle the old acrylic off, and then about 20 minutes (maybe 30) to put all the new ones on. If building from scratch, you can have a working Rapman in one day rather than three probably...
License

Arg... the KISSlicer did not make the parts correctly. It ran the ABS at a high temperature and then the parts separated from themselves ... layers had poor adhesion to each other.
sounds like the default KISSlicer settings are running too lean for your machine. try increasing the 'flow tweak' parameter slightly :)