Prop varnish and balance

[mulwyk]

I have an old wood prop that I'd like to re-varnish and balance. I've been told I can set up the prop on a "knife edge" and balance by applying extra varnish coats on the light side of the prop. Anyone have experience with this?

[Len Petterson]

Re: Prop varnish and balance

Yes it works you can take out minor unbalanced weight with varnish or paint, we did it with my friends prop for the Thorp.
We used a balanser what fits in the center hole.
It was made to balance lawn mover blades but it worked great for the prop.We checked it out on a propbalanser for a final check, found itto be perfect.
With a knife edge how would you keep it on the same spot every time?
A turned plugg in the center hole with a slot in the center for the knife edge?
Len

[Robert Lees]

Re: Prop varnish and balance

Here's what is meant by knife edges (although in my case they're round bars). The principle is to keep friction to the minimum to allow the prop to rotate to show out-of-balance.

[Len Petterson]

Re: Prop varnish and balance

Ok now I remember what you meant.
Sorry Len

[Robert Lees]

Re: Prop varnish and balance

No apologies, Len...we're all here to learn & re-learn. And then learn again.

Rob

[Forrest Barber]

Re: Prop varnish and balance

I still use a Sensenich balancing stand with various mandrels and round bar "knife" edges. then the other one uses a round mandrel with a small cable out of it to be attached above it to some hangar stucture and the prop hanns "flat". This is more like the lawn mower type mentioned.

[high time cub]

Re: Prop varnish and balance

Here's what is meant by knife edges (although in my case they're round bars). The principle is to keep friction to the minimum to allow the prop to rotate to show out-of-balance.

Robert,

That rig looks pretty high tech!

HT

[jim cooper]

Re: Prop varnish and balance

To get the best performance out of a cub or taylorcraft, its best to sand your wooden prop down as best you can, put a coat of valspar on it and hang it over your door or fireplace. It LOOKS good on the airplane but its not nearly as efficeient as the proper metal prop on the same airplane. There is a BIG difference! JC

[rotaxflyer]

Re: Prop varnish and balance

Rob,

That is a nice looking coating you got there. What type of paint did you use?

Andy

[lfries]

Re: Prop varnish and balance

Imay not go as fast as a metal prop but I do get a lot more complements on my prop.

[Robert Lees]

Re: Prop varnish and balance

Rob,

That is a nice looking coating you got there. What type of paint did you use?

Andy

After alodyning, it's two-pack etch prime, then in short order a very thin coat of epoxy 2-pack primer, cured for 7 days, then sanded then 2-pack acrylic top coat.

Tough as old boots.