Rudder Pedal Extensions

A common addition to many RV's is a little bumper on the bottom of the rudder pedal bars - the idea being that this is somewhere for your foot to push, without inadvertently hitting the brake pedal. 

An exmaple are the nice aluminium ones from JDAir - but at around $100 USD a pair, i thought this was a good candidate for 3D printing. 

Very nice AL units from JDAir

So, onto OnShape and i came up with these - they clamp to the lower bar of the pedals using some AN365 locknuts, and 10-32 Cap Head screws.

They are made as a matching pair.

How to print?

Since my dad has a nice 3D resin printer, we decided to make them using some high temp resin. They came out looking pretty good! When i went to torque up the nuts, the parts immediately cracked. Turns out the high-temp resin is also very brittle! 

Over the JLCPCB! (or JLC3DP). We decided to get them printed in 3201PA-F Nylon using the SLS method - SLS stands for "Selectice Laser Sintering" and is basically a thin layer of power that is set into plastic using a laser. A new layer of powder is added, then they layer is set. The total charge was $78 USD for both sets.

So the parts were sent off the JLC and a week or so later the blue box arrived! The parts needed zero cleanup (as SLS does not use support material) - the finish is a little grainy, but i think this suits this application perfectly.

The finish is sort of 'grainy' or 'sandy' - but is perfect for this application.

The level of detail is astounding.

I just love when stuff fits - 3D printing is pure magic.

There turned out to be a slight difference in the brake pedal pivot tabs between the forward and aft pedal assemblies, but this material machines nicely. I was able to just file some off both right hand side parts to make them fit. The screws torqued down nicely, as this material has a little bit of stretch. 

A little had to be taken off the right hand parts.

The removed material exposed the nuts, however the nut was still held enough to for the screws to go in without any issue.

You can see the reduced gap between the brake pedal and the parts on the right hand side pedal - the brake pedal is not touching the part here and has full motion. 

Parts Download 

If anyone wants to print these parts, they are avaiable for download below:

Download Link