Hello...
I read a lot about spectra line for drive instead of timing belt.
As I read the major trouble is how to drive it.
On one side there are just turn around drive wheel and possibility to line slip. The other side have line joined on center of driving shaft and then all needed length are wrapped around shaft. There are no slippage but tension change dependant of motor position. I got idea to shape driving pulley to compensate that. And I find same idea discussing in some other forum (here are stolen drawing).
So I try to calculate that "cigar shape" pulley but surprising found that pulley in not oval but just tapper!. Does anyone proved that already? My math is not the best one (well it is on low side) but I did try to simulate with simple python script. And surprisingly got taper instead oval...
And to be precise just really small taper. The data I used was:
distance from driving pulley to anchor pulley (must be constant) is 150mm
Driving pulley diameter is 15mm, grove steep is 1.5mm (like thread) and there are maximum of 20 turns on one side. The simulated/calculated diameter on the end (30mm from the center) was 14.906mm.
