Ametek Gets New Prop Blades

[coldspot]

My Ametek 30 VDC that had a prop failure





Last saturday nights HIGH winds did this

So I had to make something else for it-

This is what I've come up with so far.

I used old Hub and now have PVC blades hooked to it and

are braced with old ceiling fan mounts against the pushed

on side for better strenght I hope.

Old blade=

19. " out from hub center
    
4. " width start to 5" at ends
   
18. ` pitch full length
    
    

(before added aluminum add-ons)

New blades=

21. " length from hub center
    
1. 3/4" wide at start to 1" at ends
   
25. ` pitch at start decurving to about
    
    

ftat at tips.

Can't wait untill reinstalled on tower tomorrow,

Hope to get more RPM maybe.

[coldspot]

Well it's been up about 15 min now and so far

I can see that it's going to take a bit more wind

to turn this than it did to turn the "Ceiling Fan" blade

version.

The Ametek will have a "tiny-bit" more drag than before because

I've added a weather seal around the shaft to help protect

the gen from water on the shaft.

Also got a "Trim Blade" 5 blade version finished

for the "Servo" motor.

This would turn a bit in the very light breezes tonight

put the "Servo" motor will take a lot or RPM's to get any

power going. It would only show about 6 V DC with cordless Drill

spinning it. I checked when I had to see what way I wanted the

prop to turn to keep the wires as colored: Red = Pos with black = Neg.

This one is set-up as a counter clock-wise.

Trim being 2 1/4" wide full length of 26 1/4".

Being the Airplane wing type profile I tried to sand to

and then mounted to a flat surface they get about 19-20`

Pitch full length.

A the "Servo" motor is the only one I've got being 3/8" shaft

and that size being pretty easy to come by, with the plate,(Lock coller based)

I used being one of two I got last week,

I might go ahead and open this one up to 1/2", for use on the conversions.

 

[coldspot]

Well

I'm going to call that a complete failure.

It has not turned even one rotation yet.

I think bigger blades might do better but

will have to build and then test.

That set sat very still while I

walked around with the trim blades

spinning very well on the servo motor,

at 5' off the groung while the Ametek @ 14'

did nothing but track the wind direction for me.

The ceiling fan blades used to turn in any wind,

If I wasn't saving for a 28 Volt DC Gen I saw

and then hid very well at the Army Store,

(This unit was about three times the size of

an auto alternator).

I'd buy more ceiling fan blade mounting brackets.

Lets see, Hmmm... I could buy two sets of brackets,

OR.. I could but that 28 VDC Gen, Hhmmmmmm......  

[coldspot]

After pulling it down to rebuild-

I noticed that I had gotten a bit carried

away when I had tighted the screws down and

Ended up with a blade that had clockwise pitch

toward the inner part and then it was counter clock-wise

toward the outer half.

This has been fixed by adding a few more nuts

Under the screws that hold the inner pitch up setting

to keep the PVC from getting turned that far.

Now it's set-up with what I has trying to get.

But of course, more testing will tell.

Still might end up heating the blade tips

and bending them a bit more if I can build a quicky

jig to hold them till cooled and set.