Ultimate Ratcheting Bar End Friction Shifter

This is an almost fully 3D printed friction shifter. This is a project I have been working on for over two years, on and off. This model is the latest and greatest iteration! It uses PETG plastic for its favourable properties but also its cost and finish. The parts are intended to be printed without the need for post processing. Supports are also not necessary, but may help with overhangs depending on your printer. The friction surface is done by inserting washers which give a buttery smooth operation and feel. I use this shifter on my personal bike daily, and it has been very reliable so far!

I use this shifter on a 1x7 setup, with an 11-28 rear cassette (the Netherlands is very flat!), so the range I need is only small. However, I deliberately made the barrel of the shifter much wider then I needed (20mm wide), so I hope it should work with larger rear cassettes (I hope up to 11 or 12 speed, but I can increase it more if necessary). 

Features:

• It has a built in ratcheting mechanism, to counteract the strong spring present in derailleurs. It allows the shifter to have a lighter action then a purely friction based one.
• The shifter can be completely added or removed from the bike, without needing to ever remove the derailleur cable run. This makes tinkering, testing and replacing the shifter easy and painless.
  • The dual holed cable guide on the shifter itself allows the shifter to be removed.
  • The cable guide on the shifter mount (shifter pod) allows removal of shifter pod.
• The use of a quill-style clamp provides a snug fit for different bar end diameters.
• The outer housing cap has a notch seating it in the shifter pod, which means only the shifter itself can move, even if the bolt is loose. 
• Cheap as chips to produce!
• Uses washers (nylon/metal) so shifting performance is always good and consistent regardless of printer.
• The print is reversible, in order to print a shifter for your front derailleur it is only necessary to flip the shifter pod in your slicer. 
• Limited to no post processing required.
• The bolt for the shifter can be tightened using an Allen key or by hand, so it can be easily tightened out on the road. 

Print Settings:

I printed on my Bambu Lab A1, with a 0.4mm nozzle diameter

• 0.12mm layer height in general
• 0.08mm layer height for the bolt and sleeve nut, so that the threads form properly
• 100% infill
• 4 wall loops
• No supports (although supports for the shifter pod and shifter itself can help with the overhangs)
• Ironing (on top surfaces) - this is not necessary, but can be nice.

Hardware (per shifter):

• 1x nylon washer:
  • I use M6x18x0.9mm nylon washers https://www.aliexpress.com/item/1005006136471084.html?spm=a2g0o.order_list.order_list_main.59.4da11802d9G35y&gatewayAdapt=glo2nld
  • Metal washers can also be used in place of nylon ones. Although the washers must be 1mm or less in thickness, and I would strongly recommend around 18mm width.
• 1x Long M5 Bolt 
  • Anything longer then 45mm should work well
  • I use an M5x70mm bolt - https://www.aliexpress.com/item/32968483467.html?spm=a2g0o.order_list.order_list_main.74.345b79d2qdxMtD&gatewayAdapt=glo2nld
• 1x Square nut (M5x10x10x3mm) - https://www.aliexpress.com/item/1005004253509147.html?sourceType=1&spm=a2g0o.wish-manage-home.0.0&gatewayAdapt=glo2nld
• 4x M6 washer (M6x10x1mm) - One washer for the long quill bolt, one washer under the sleeve nut and a washer on either side of the shifter itself.
• 1x M5x15mm sleeve nut - https://www.aliexpress.com/item/1005002212964541.html?spm=a2g0o.order_list.order_list_main.142.296d1802UQFjl2
• 1x M5x12mm T-head bolt - https://www.aliexpress.com/item/4000239470157.html?spm=a2g0o.order_list.order_list_main.167.296d1802UQFjl2

Some other notes:

PETG should be fairly easy to print. This shifter may not last quite as long as standard metal shifters, but you should not need to worry about durability! I would strongly recommend not using PLA as I do not trust the reliability of the material in this application. In my testing PETG is ideal, but a carbon nylon filament may also work for extra durability (but watch for surface finish issues).

Feel free to ask me questions, or if you would like me to alter the model slightly. I would be happy to.

Have fun!

Harry