I've been searching for a way to adapt the 3/16" Dumas Driveshaft/Stuffing Box to the world of Metric. I found some spacers on eBay that go from 3/16" to 6mm. I was then able to source some GT2 6mm shaft pulleys! Right now I'm looking at the following math.
x2 750kv Outrunner motors on 3s Lipo = 11.1volts*750 = 8,325 Max RPM
x2 750kv Outrunner motors on 2s Lipo = 7.4volts*750 = 5,550 Max RPM
Geared down 2:1 (20 tooth motor Pulley and 40 tooth output shaft) = 8,325/2 =
4162.5 Final RPM
Geared down 2:1 (20 tooth motor Pulley and 40 tooth output shaft) = 5,550/2 =
2775 Final RPM
I really like how the math is working out. The target RPM for the Dumas Props is 2-3k RPM. If I want to speed around I can run 3s or tool around on 2s.
Using a hammer, I tapped the spacers into each side of the 40 Tooth Pulley. Nice and tight fit!
Then I used a 3.2mm drill bit to create holes in the spacers, while trying not to hit any threads for the set screws.
I will have to shorten the shaft, but everything is lining up just how I want it! I'm trying to keep all drive train elements behind bulkhead number 5.