Foam replacement for Spektrum SLT3 and Arrma ATX101 transmitters

I really dislike the foam feel of RC car radios.  I decided to design a replacement for the SLT3 used with my Arrma Typhon 3S.  This part will fit any SLT3 transmitter, which comes on most all of Arrma's 3S line (Typhon, Granite, Senton, Big Rock, Vorteks, and Vendetta).

Replacement is easy: just pull off the foam and push this part back on.

This part must be printed in a flexible filament.  The filament used here is Fillementum Flexfill 92A in black.  I recommend 0% infill with 2 perimeters (assuming a 0.4mm nozzle), as in the attached GCode, which gives the wheel a very satisfying, squishy and grippy feel.  If you prefer a firmer wheel, I would use Gyroid infill at 20%.  Rectilinear and most other fills will give an uneven feel around the wheel.

Update: I added a variant for an Arrma ATX101 like those that come with the Granite Voltage.

Update 6/11/22: I adjusted some of the dimensions for the SLT3 and created “v8”, which deprecated “v4”.  I reduced the inner diameter by 1mm for a slightly more snug fit, and increased the depth by 1mm so that it fills the entire wheel.  I think it's pretty dialed-in at this point.