Hello,
Good video. Nice looking Vawt rotor. Of course once you hook a load to it, it will slow down some.
Big yes to the steel backing. Gotta have that. Even sheet metal on the back side would be better than nothing. I always wondered about trying to use some cheap epoxy to tightly glue a few circles of sheet metal together with clamps and two pieces of plywood as glue blocks. Not as good as solid though, but maybe worth a try if cheap.
I know that 'gearing' is not used that often around here, but for a VAWT I believe I would certainly do it now instead of attempting a 'direct drive' alternator-- but only if there is no cogging. I would not try it with a dc motor including Ameteks for that reason. The cogging would be multiplied by the gear ratio.
The direct drive VAWT alternator I made had 20 poles (and nice 1/4" thick steel rotors) and DID have a cut-in of only 70rpm. But the problem was it is exactly like the gearing on a 10-speed bicycle. Going down that low of a cut-in was like a kid trying to start off pedaling the 10-speed bicycle in 10th gear, and thus the TORQUE to turn it was EXTREMELY difficult at this 70rpm cut-in. So it was always Severely (mechanically) STALLED (Too much TORQUE needed) unless a hurricane came along-- and even then I only got 62 watts max during a brief giant gust.
One of the great easy things about HAWTs is you get to proportionally divide up (or;reduce) this hard to turn TORQUE with increased (easy to turn) SPEED.
Of course, in the end, TORQUE x SPEED still equals the same total power present.
But I have found it extremely difficult to guess a PERFECT matched direct drive alternator for a VAWT. I think It would be much easier (and cheaper) to do simple gearing for higher speed and then you can get more leeway to get into a decent efficiency range for the alternator. (just my opinion from my frustrating experiences)
Something you might find useful:
I just got a low friction rubber flat belt (5/8"wide by 1/8" thick by about 3 feet diameter) at a car parts store like 'Autozone'. (only $13)
It works great on my pedal generator. Sure seems as easy to turn as a chain and sprocket. I use it on particle board circles as 'pulleys' I cut out with my jigsaw.
The belt also grips very well on plastic pvc end caps--as the 'small pulley'.
It will work with your decking material board too. Simply cut out different size circles until you get the exact 'gearing' from your Vawt rotor to your Vawt alternator. (I would make a 'weak' (not strong/powerful) alternator with a cut-in around 120-220rpm and gearing of 3:1 to 5:1 ;3-5 times the speed for the generator)
-Sorry, Difficult to explain in few words. Good luck with it. You are on a very bumpy road.