Making TD 0.020 Snap Starter Spring

proctor wrote:Got round to making a spring to night, is it perfect ?, no. Did it start my
TD 0.020 ?, yes.
Learned a lot though, spring I wound earlier was wound on 10mm
mandrel. (Drill bit, wound on shank) It was about 2mm large on diameter.
Used an 8mm drill tonight and finished coil was 9/16" instead of required
1/2", this is not good, better too big than too small or coils bind up
when you backwind.
Heated end that goes on press nipple to red heat and let cool, formed
eye for round nipple. You must wind this little loop in correct direction,
anti-clockwise, for it to fit over properly and tighten it's grip when
you backwind. At the other end, bit that hooks prop, heat only the
end 3/8" to make little loop, you need spring to remain in rest to retract
after it does it's work. My crude effort on left TD 0.010 on right John
Photo https://i.servimg.com/u/f46/17/26/04/06/spring11.jpg