Prop balancers

[Roflhat]

I've been looking at a couple of designs of prop balancers (static),
anyone on here got one? I'm considering making one. Theres a company called Stuhr that makes them and they look really good, but very pricey £££!

[Roflhat]

anyone got one?
I'd like one like this - Attachment 54292

[zul8tr]

anyone got one?
I'd like one like this - Attachment 54292

The image does not come up? Post a different way

[Roflhat]

oops, try this: http://www.rundquist.com/images/stuhrpb.jpg

[zul8tr]

Those are the typical static balance devices. Not cheap but effective for stage 1 balance. While they will tell you where the heavy area is in one plane they willl not tell you where on the blade to remove material, i.e at what radius and area out from center, closer in remove more or farther out remove less, experience definatly needed here. Any object can be statically balanced and not be dynamically balanced and still cause problems.

[Roflhat]

That's what I'm after really, just to get props/flywheels a bit better balanced. I was just going to take it slow, remove tiny amounts of weight at a time until it's balanced.

[Roflhat]

I'd like to have a go making something like this: http://www.pinoyboats.org/forum/viewtopic.php?t=2531
any idea where I'd find discs like them?

[phillnjack]

the balancer in the video is the same as used on rc boats just scaled up.
very simple to make
BUT you have to get the balancer shaft balanced before use ? and make 100% sure the ground it sits on is level !!!
then just use it very simply and very effective.
dynamic is a wastoe of money, simple is all thats need for boats.
as we dont blance gear cogs gear shafts,bearing carriers etc etc,so stick to the simple balancer and enjoy.

first time out it will lose a certain amount of balance anyway.


phill

[zul8tr]

RC boats mostly use a static magnetic balancer (less friction for these small props that need a very sensitive balancer). Some sophisticated RCers use a dynamic balancer as well. As far as dynamic being a waste of time that depends on the size and weight of the prop and cost of the dynamic balance. Do you think the large ship props and aircraft are just static balanced? No way! They are or shaft bearings would go to pieces and down time is costly. Some examples:

http://www.centralhobbies.com/props/balancer.htm

http://www.rundquist.com/how_balancing.htm

http://www.modelpowerboat.com/conten...ller-balancing

http://balancemyprop.com/

As far as the small outboard and race props the static balance does work very well provided the prop tech knows were to remove metal to keep all blades close to the same dynamic balance by Experience. With surface piercing props there is an automatic out of balance that occurs because of it's operation in and out of the water and very variable blade loading, but still if dymanic balance was available for a reasonable price it would be worth while.

I know this is not a prop but would you run your car tires with just static balance? Might work but most likely will not and dynamic balance needed.

[Roflhat]

Something like that first link would be ideal (obviously scaled up). Especially if could do flywheels too.

Funny you mention tyre balancers, a similar idea went through my head- whether it would be possible to modify a wheel balancer to do props and flywheels? Because you must have to put in the wheel diameter, so maybe you could make it would?