slow progress

[birdhouse]

hello all-

it's been a while since i've posted.  my previous questions were about different motors and how to use them for wind.  i picked up a fanuc motor and began the process.  just thought i'd share how far i have (haven't) gotten.  

the motor is a 2,000 rmp, 140 volt 3 phase, 20 amp.  i hope it does ok as a 12 volt machine.  my metal work is very similar to hugh's/dans/most of all you.  the big difference is how i had to attach the motor to the yaw tube.  in the photo there are two bolts holding it in place that are obviously way too long.  i haven't quite figured out how to attach my blades to the funny taper shaft of the motor as of yet.  

i settled with an 8.5 foot diameter and laminated the blades out of clear fir, then used the chainsaw method to rough them out.  they are nearly completed

blade stock-

almost completed blades

metal work

thanks for all of your help for getting me this far along!

[wingman1776]

I also have a faunc servo motor looks very much like yours.I have pics in my diary. I got the brake out of mine and tested it the other day. With a right angle drill I have and at 400 rpm it put out 13.9 volts and 17 amps into a small lawn mower battery. I think it will work good for 12 volt. I was thinking about 8 foot blades too. I am way behind you tho no metal work done yet or blades. How much off set did you use? You going to rotate clock wise or counter clock wise? I have been looking for a taper shaft adpter but have not had any luck. If you come up with a source I would be interested. I have also been looking for a connector for the factory wire connection. I think they would work great and be water proofed easy. I have yet to find source for one of them either. Do not even know what they call that kind of connector. I am sure that would help. I hope you post how well it works when you get it in the air. I will be watching and hoping it works out well. It looks great so far.

[birdhouse]

wingman-

yes, we have the exact same motor.  i too have the brake removed.  it is promising to see that @ 400 rpms you are seeing close to the full 20 amp rating of the motor.  i was wondering about that.  i used 6% offset (of a 100" prop) which was about 6 inches.  i read somewhere on this site that six percent would (if anything) be on the early side of furling.   i figure it is much easier to add weight to the tail than to remove it.  i also plan on mounting the rig on my pick-up to test where it furls...  i will be rotating clockwise.  i think it is better for the giroscopic forces while it furls.  the electrical connections are easy.  i just soldered (and wire nutted) #6 wire to the existing three phase wires and gave enough length to connect to my "tower" wires.  forget the factory wiring harness, it is meant for complex control mechanisms.  if you've had it apart, the three "power" wires should be very aparent.  the taper shafts are tricky, i think it may be a "morse" taper, but unsure.  thank god i know a machinist to help me make a mating plate.  i may be able to make two if you're so inclined...  

good luck! and thanks for the encouraging words!

[Ungrounded Lightning Rod]

Are you going to put a second tail boom out the back from the top of the tail hinge, making a long, narrow triangle?

It can be small.  But I'd really rather see the tail boom weld loaded in compression than in bending with a LONG lever arm.

(Or at least put a reinforcing rib on the hinge-boom joint.)

Also:  That boom pipe looks HEAVY.  I hope it's not too heavy to furl early enough for your genny.

[birdhouse]

thanks for the advice ungrounded lr.  i was planning on putting some small plate stock gussets on it to reinforce the tail boom joint.  plus it is welded very heavily.  the upper furling stopper hits on the motor frame , rather than the yaw tube...  this should reduce some of the leverage.  i agree that the boom stock is heavy pipe and plan on using 1/8" aluminum sheeting i've got around for the tail.  this should be lighter than plywood, and hopefully last longer.

this mill is going out at my cabin where i cannot be all the time, so i want it to furl earlier than later.  i will not erect it til i have mounted it to the front of my truck (connected to batteries that need charging) and have a pretty good idea of the furling moment.  if the pipe does infact need to be smaller/lighter than i will proceed along those lines with an additional brace.  i'm really hoping that it can stay as is.  

what are your thoughts on a wind genny that is unattended for 95% of the time?  i was planning on lowering the tower over the winter months as i can't get up there because of too much snow.  during the summer would you short it while away? or let it run the dump load all the time?  was also thinking about running a few lights 24/7 to ease the dump loading?  any thoughts?  it makes me very nervous to be away for a month at a time with it spinning.  it also makes me nervous to have it shorted for a month too.  any thoughts on this would be much appreciated! and i really don't want to build a mechanical brake, but guessing this is what you are going to suggest.  

thanks!

[jlt]

looking at your pictures it looks like the blades will be very close to the tower.you might try mounting to the back of the motor.and it will furl better and offset the weight of the tail.looks like it should be a robust unit .

[birdhouse]

thanks for the compliment jlt!  

i hear you on the blade to tower clearance.  i did incorporate a 4 degree tilt to cheat the blades away from the tower.  mounting the motor in front of the framework is a creative solution.  i would worry a bit about it since the motor isn't designed to be mounted that way, and the mounts are aluminum, but i guess it isn't designed for any of this wind genny stuff anyways.  i'll have to bolt it up and see how solid it feel in front.  

i understand the greater the offset the earlier the furling, but how does up wind or downwind movement of the blades in respect to the yaw tube effect furling?  in my head (wich doesn't always reason correctly) it seems like the further you were to move the blades upwind (forward of the yaw tube) the harder it would make it for the machine to furl, but that is just a guess.  anyone have any concrete info on this?  i find it odd that in hugh's book the different sized machines have different front to back clearances between the yaw tube.  these clearances don't seem to corrolate to size either.  

thanks!