Loading

Reprap Prusa i3 Rework - X END IDLER - With belt tensioner

by ramkam, published

Reprap Prusa i3 Rework - X END IDLER - With belt tensioner by ramkam Jul 13, 2014

Thing Info

18639Views 3648Downloads Found in 3D Printer Parts
Report Thing

Summary

Mod of the X END IDLER. Added a tensioner for the X carriage belt.

  • installed it, it works.
  • Some suggested that using the other design with 3 bolts is needed for deformations and stress distribution on the z bearings. I didnt see that issue when i assemble it. Also i ran an FEM analysis, and i get the same outcome : it doesn't seem to be a concern.
  • Ran another FEM on the ball bearing holder ("roller puller"), it should be ok as long as you stay below 10Kg of tension force. Less than 2Kg force should be more than enough to get the belt tensioned, so, it's on the safe side and has provision for fatigue. Just print it with the same orientation than on the pictures of the assembled part, and slice it with 1.4mm wall thicknesses.

Instructions

-- Assembly :
Print the X END IDLER and the Roller_Puller
Insert a screw in the roller puller, head of the screw goes in the socket (you may need to cleanup the hex socket a little, and to bend very gently the arms while pushing the screw head to its slot).
Insert the screw & roller puller into the X_END_IDLER bore, add a nut, et voila you have your belt tensionner
-- Careful:
The point in having this part is to be able to dose carefully how much tension you want to put. Dont tension the belt too much or you may endup putting too much stress on the tubes that contain your z axis roller bearings.
You may want to add a washer before the nut to even out stresses, and to use a nylock nut so that vibration during prints doesnt make it turn and go away.
-- Printing
I use a full metal extruder, so i printed with ABS at 240°C to get strong bonding (dont go that high if you have a JHEAD you'd destroy the peek)
Slicing done with Cura, with infill 30%, wall thicknesses 1.4mm top bottom 1mm. Seems to be rigid enough like that.
Printing done with the i3 at 30mm/s external sides, 50mm/s inner sides and 70mm/s infill, and extrusion rate at 110% to get some more chances of layers bonding.

More from 3D Printer Parts

view more

Thing Info

18639Views 3648Downloads Found in 3D Printer Parts
Report Thing

Liked By

View All

Give a Shout Out

If you print this Thing and display it in public proudly give attribution by printing and displaying this tag. Print Thing Tag

All Apps

This App connects Thingiverse with Makeprintable, a cloud-based mesh repair service that analyzes, validates and repairs most common mesh errors that can occur when preparing a 3D design file for p...

App Info Launch App

Kiri:Moto is an integrated cloud-based slicer and tool-path generator for 3D Printing, CAM / CNC and Laser cutting. *** 3D printing mode provides model slicing and GCode output using built-in...

App Info Launch App
KiriMoto Thing App

With 3D Slash, you can edit 3d models like a stonecutter. A unique interface: as fun as a building game! The perfect tool for non-designers and children to create in 3D.

App Info Launch App

Hi, what bearing size I use with this ? Thanks!!!!

Same as the original one or whatever has the closest match to the diameter of your pulley.
In the original build, it's 604ZZ.

Which screws need to secure the belt tensioner?

the screw the goes from the inside to the right (parallel to the rods). There's only one like this. It's a 4mm screw.

Hello, I have a question about this Idler, there's any chance that work with a 608zz bearing, or you have a parametric version of this idler?
Thanks in advance.

Oops, might have missed the mail notifications, sorry for the late reply.
Not sure it can fit nicely. The 608 is 7mm thick instead of 5mm for the 604; also, it's better that the bearing and the pulley (on the other side) have more or less the same diameters otherwise you'd get plenty of issues. So, no.
Regarding parametric, well, it could be interesting to trace the dependencies between the different components. Not sure it will model in the form of a tree, probably more of a graph. Would require lots of work. Is it worth it ?

Mar 17, 2015 - Modified Mar 17, 2015

I'm not sure if anyone was able to print it without enabling Support in Slic3r, but I think it's a must, otherwise top part (overhang) just collapses during print...

Hi bratan, you need to use supports for this one

Thanks! Yeah it printed fine with support. Now I'm having problem printing pulley (top of each ear "melts") but that's just issue I had with my i3 for a while :)

The overhang of the ears is small, it should go ok. try slowing down the print speed, it will give more time for the filament to cool down and give better results. Also, the ears are just there to prevent the bearing from sliding sideways, it's not important to have it perfectly printed. The arms on the other side will take some efforts, so print them well and slow

Yeah overhang there is not an issue. I think you are absolutely right about speed tho, I also suspected something like this especially since I increased edge printing speed recently... Thanks again! :)

This comment has been deleted.

Please, you can make X-END-MOTOR for m6 studs and nuts , or where i can find a model for editing ?

Hi Mobsman, the parts in scad format are here http://reprap.org/wiki/Prusa_i3_Build_Manual#EiNSTeiN_VARIANT and you may find variants and stl files by searching prusa i3 on thingiverse. Regarding the model, i only have made mods to the idler.

Top