My original printer was made from components salvaged from a 1980's xray copier. Great stuff but way too much mass for quick printing. So I am building up a H bot with MakerSlide. This will have a lot less moving mass.
The H bot requires six pulleys to guide the belt around the figure H. I created a simple bracket that fits in the 20mm t slot. I designed in a nut holder but I put it at the wrong orientation so it won'f fit in the slot as is. Rather than reprint, I just put a 6-32 screw and nut in the track to prevent the bracket from moving in the slot. It fits pretty tight already but there will be belt tension so it should have a mechanical fastener. I used 10-24 machine screw with some washers to ensure clearance to hold the pulley. The Inventables pulley I used has a slight interior ridge on one side which prevents the bearings from centering. I filed off this ridge and used one washer on each side.

I uploaded a single bracket and a set of five. Make sure your single looks good and then print the rest.

UPDATE: I took a file to my original set of brackets. If you are going to make these, I suggest making the embedded nut deeper so it fits the slot and countersinking the screw hole that connects the slot nut. For belt clearance the slot screw needs to have a flat head.

I would also put a circular bump on the inside of the bracket so it doesn't need washers. And if the bracket sides were a little thicker it could have an embedded nut for the bolt going through the pulley.

My steppers have machined pulleys fixed on them so the normal couplings do not fit. These fit perfectly.

Update 3/25/13 REV 1.5:

I made quite a few changes to the original design of the parts, for the better I think. I am planning on using the 3 pulleys that I just printed out on the job tomorrow. We are pulling a long section of fiber and are short handed. I am hoping to use these in place of some bodies. The plastic will be nice because there is very little risk of cutting into the outer jacket. I made use of the Acetone bath technique for finishing these pulleys. It looks like the acetone and ABS solution really helped seal the outer shell. I am hoping they resist cracking at the seams now. See the change log for more info and see the photos for the updated version.


REV 1.5**
Change Log:
- Increased diameter of hole in the roller and frame. There is now minimal (almost no) post processing of the parts required.

- Added a single roller to the design.

- Removed decorative loop on top of frame

- Decreased diameter and changed the shape of the end cap post to reduce overall post processing. End cap may require a touch of glue to stay secure now.

- Changed to shape of end cap receiver in the rod to reflect changes in end cap post.



REV 1.0

I made this just to have something to play with. I might print another and hang my spools with them. As of right now this thing doesn't fit together with out some modifications. I had to ream out all of the holes with an exact-o knife and ended up glueing on the end cap of the rod. I am still new to 3D printing but I can see that this design does not compliment the material. It is still fun to play with though. Let me know what you end up using it for. I included the sketchup file. Feel free to fix and repost. :)

X axis upgrade to vertical X, extruder and carriage to suit the Makergear stuff, pulleys of my own design, y motor mount upgrades... blah

A slightly more printer friendly version of the small x and y belt pulleys found on the Reprappro Huxley and Mendel (and probably other printers that use a belt of the same type).

I was having issues printing the .stl that reprappro provided because Slic3r was trying to get my printer to make two round shells and then extrude tiny, lonely drops to make the teeth.
(https://github.com/reprappro/Mendel/blob/master/Print-mendel/Individual-STLs/pulley-2off.stl)

I made the teeth on the gear more pronounced by reducing the inner diameter, making it easier to get more defined teeth by convincing Slic3r to print all of the teeth in one shell.

Drive pulley for 3.81mm pitch synchromesh cable found at SPD.

This is a rewrite of the code by droftarts to see whether structuring a library like this using a cleaner separation of data and code and a functional approach (no global variables) would help in understanding and reusing the code. This work is offered in all humility as a product of my own attempts to learn openscad. I have only tried this on a few simple cases and not printed from it.

A modification of the filament pulley to accept a common 608 zz bearing, m8 bolt and 3/4 inch dowel.

30 teeth MXL plotter pulley for drive any 3D printer with low cost plotter pulleys 8€/4meters

original pulleys are to small in my opinion, belt tends to hop a bit, 12 tooth pulleys have 53,4something steps in Firmware.

deep teeth with centering geometry, for smooth and consistant belt movement

5mm shaft diameter

This is a 20 tooth XL series timing pulley for 3/8" belt and 1/4" shaft.

After buying the Printrbot Plus in November 2012, I noticed the 10T Pulleys on the X and Y axis were slipping. So here's an enhanced version that will provide a long lasting grip and more customized fit. I have printed this and use it on my bot.

Update : See "Ferris Wheel (yet another)" for the latest.

Motorized Ferris Wheel created using Sketchup, Makerware and a Replicator 2. "Ferris Wheel.mov" and "Ferris Wheel Backside.mov" are now included in the download to see it in motion.

The Idler Pulley Bracket is fixed laterally by 4 screws and has 2 additional screws for belt tension adjustment.

Note, Jan 20, 2013:
The Idler Pulley Bracket for the X-Axis needs some modifications, I'll upload a new version soon.

Update, Jan 20, 2013:
X-IdlerPulleyBracket.stl uploaded *.

Update Jan 21, 2013:
IdlerPulleyBracketV2.stl uploaded.

Update, Jan 27, 2013:
Added MisumiSpacer for the X-Axis.

A filament pulley used to guide the filament from the spool into the extruder.

This OpenSCAD script makes many different types of pulleys for just about any sort of timing belt. This latest version adds support for shafts that have a flat, for multiple nut sizes based on the shaft diameter, adjustable flanges, and for making pulley sets, where the second one is based on a ratio of teeth from the first one. The prior version added support for any number of setscrews and allowed them to be at an angle. The original (By Erik de Bruijn) supported threaded shafts with a recess for a nut to hold the pulley in place, or an even number of set screws printed in a hub with a (capped) teardrop hole. The original works well with the Synchroflex(R) timing belt,1500Lx10Wmm from RS (order code 474-5892), spliced in half (to 5 mm width).

I'm about to build up the great Rostock concept:

thingiverse.com/thing:17175

as T2,5 timing Belts are much more available for me than the GT2, I was looking for a pulley with a matched size, so the original configurations can be used. As i couldn't find one, I calculated it, and made one.

Update: I Changed the teeth-structure, should give a better grip. Feel free to inform about problems in size or grip etc.

About a year ago I discovered a very inexpensive source for 18T plastic pulleys that appeared to be nearly perfect for 3D printer and other robotics projects. (Then I came into some metal pulleys, so I abandoned this research, but in sourcing pulleys for a 3D printer project at a local school, I decided to take it up again.)

The pulleys I found are for hobby cars. They're 5mm bore, 18T pulleys with a 3mm tooth pitch that appears to be a standard curvilinear profile, like HTD. In fact, one of the mating belts appears to be Bando Synchro-Link HT. IMPORTANT: I have not verified that a standard 3mm HTD belt will fit them -- so if anyone has one, please chime in with some good news!

These are US$9 for four and widely available. They're called "Duratrax Timing Pulley 18T Street Force GP", often listed under item number DTXC9698. They have a groove in one side that's meant to receive a metal pin that holds the pulley in place.

This adapter is fully parametric so it can be used for other pulleys, but it's set up to fit this pulley in particular. You can glue this adapter against the pulley, and then fasten it to the motor shaft with the captive nut and a 3mm screw.

A parametric crowned pulley, inspired by DaleDunn's.

I liked this idea over the flanged bearing covers, but I couldn't get a bearing to fit the original and thought it wasn't wide enough. With no access to SolidWorks I figured I'd redo the thing in OpenSCAD.

The second photo shows the size difference between DaleDunn's and mine.

This is an openscad script to generate a pulley for strings and ropes. It uses a 608 ZZ bearing (the cheapest and most common ones, used for skateboards and rollers, about $1-2 on ebay).

With the source, you can tweak most of the properties, or use another kind of bearings.

The groove cover, attachment leg and top housing are optional.

I use these to lift bags of bird seed in my garage, out of reach of mices!

The pulley is to be screwed or nailed to a support on its own axis. However, the optional top cover makes it possible to hang it. The last picture show how I reinforced one that lifted about 50Kg.

Pulley for my wooden rostock variation. It's made for 0.5mm Dyneema.

Timing Pulley MXL 50T, 6mm bore for a prototype aerial camera gimbal I am designing.

Video here: youtu.be/bSbYbVXHCSA

Neat little two piece pulley and block so fit on top of an 8mm or 5/16" threaded rod, or screw it to the underside of a shelf above your printer.

The two pulley halves just fit together without the need for glue.

this is the best filament feed system I have come up with, it is very fast to change and lets you run multiple spools on a rack beside your printer thingiverse.com/thing:28944 or between them like I have done here.

Mine clips into the top rails of my Mendel Prusa via the mounting clamp I have used on other similar projects.

Einfache aber große Umlenkrolle für die Deckenmontage für sichere und kraftlose Materialzufuhr.

PULLEY T5-18T with 5mm shaft

Side guide for 608 bearings.
These washers do not brake the bearing.

Upgraded to the Gt2 32 teeth pulleys and only to realized they don't fit at all. Designed a new Y bearing guide that offsets the 608 bearings back a few to make everything fit.

By all means, go for a 18 or 25 teeth instead, don't make the mistake we made!

I was wondering if the belt on the Y-Axis on my orca would stay on its bearing as there is no guide...

It should work as other useres indicate, and i myself have been running it for quite a while.
As long as everything is perfectly aligned it will work.

But, as the devil never sleeps and as i had one incident where it fell of i decided to make a snap on guide.

Eventorbot! Open source 3D printer. Simple with less materials. Frame is made of a single 4' long, 2 1/2" square tube (16 gauge/1.5mm/.0598" thick, cost: less then $20.00). With the design there is less plastic parts, stronger structure, all wires are hidden, and a more appealing/finish look. The blue print file will get you more familiar with the construction of the unit. The downloadable file is my blue print that I designed and used to build the machine. The accuracy is to the exact of my build.
For more images and updates like:
facebook.com/pages/Eventorbot/111169638934671

The unit is supposed to resemble a robotic arm with hydraulic tubes. It was designed for prints to be less affected by vibrations. With the 1 solid frame, any vibrations of any axis will cause the other axis to move with it. For example: If the X axis causes a slight vibration/1mm movement to the right, the Z and Y axis will also move that 1mm to the right. This will result in a better print as everything will remain squared.


For those who do not have access to a 3D printer. You can order the plastic parts and frame at: kickstarter.com/projects/1874396831/eventorbot-open-source-3d-printer

Eventorbot has met its funding goal!

Well, I'm speechless and overwhelmed with all the support. I will like to say a BIG thank you for all the support, kind words, and to all the backers. To be able to share and have your interest in something I created is a great feeling. Everyone of you guys have made something that was a big dream become reality. Eventorbot, as a 3D printer is now going to happen! You will have no regrets in owning a Eventorbot, our machine will be a strong contender.

Thank you... thank you... thank you...

Accessing the idler pulley on the X-Axis for oiling requires a lot of stuff to removed to gain access.

You have to remove the Y rods, X rods and the platform, then unscrew the idler pulley bolt to remove the top plate to gain access. This is a pretty good incentive to put up with awesome squeaking.

With this thing, disassemble once more, then never again. You just unscrew the 2 bolts on top and oil away !