2026-09-21

Last modified: 2026-09-21 10:38:38

Cyclecar spring shackles

I rummaged through the drawer and found a 2-flute end mill with one flute very badly chipped away and one flute quite badly worn.

I set up speeds and feeds for a single-flute cutter, on the basis that the badly chipped flute won't be doing anything.

I also reduced depth of cut from 1mm to 0.5mm.

And successfully completed the job!

And mounted on the chassis:

And I can now "jump up and down without leaving the floor" (I think "jouncing"?) on the chassis, at approximately the midpoint of the spring, and it stays nice and flexible, doesn't bottom out, doesn't lock against the chassis.

Apparently "jouncing" allows you to put about 3x body weight into the ground. 3x my body weight is about 3kN, and 3kN is about the absolute max. load I am expecting in a harsh bump, so this is adequate I think.

So, good.

As a bonus, the old shackles are still available in case I have a need for a 60mm link, 25mm wide, 4mm thick, with 10mm holes. (Steering arms?).