I am thinking about getting one of these.
http://www.rpxtech.com/DynavibeClassicPropBalancer.html

Has anyone used one?
Any good?
Waste of time?

Thanks

I love my Dynavibe. I use it on everything from Pilatus pc-12 to super cubs.
I have been using one for a little over three years. I use it about every month and it works just as well as the 10-15k balancers. I rarely need more then three runs to get under .07 IPS and on the turbines i can almost always get .01 or .00 IPS
I have only had one problem with an accelerometer going bad the first year. They replaced it for free.
Really the only difference between this one and an expensive balancer is it does not give a weight solution. It just gives you the vibration (IPS) and the angle location. Its up to you to figure out how much weight to add. The expensive balancers will tell you how much weight to add and compute the changes with later runs. Dynavibes new GX2 will do this but the classic works just fine and is half as much $$$. Having to guess the weight gives you a bit of a challenge on the first run but once you figure out the propeller/ engine combo you can do it much faster on later dates.
You might get a reading of say .1ips and @ 180 degrees. You will have to add weight at 0 degrees to counteract this. You might start out with say 20 Grams of weight. The next run you might get .05 and 180. Its pretty simple math at this point no matter the change to find out how much more weight you need. You then add 40 Grams total weight at 0 degrees and if your lucky you would get .00IPS.
It will take a glare shield thats vibrating up and down to smooth. My cub radio would shake so much it would turn the volume knob up on its own and blast you with full volume 5 minuets later, no more auto volume after. My chieftians would get vibration in the pedals. That is gone. With turbines the change is profound.

My girlfriend loves it... Uses it a couple times a week. Uh... oops. Never mind. Got confused......

bigrenna wrote:My girlfriend loves it... Uses it a couple times a week. Uh... oops. Never mind. Got confused......

That's some funny stuff!

I don't have any experiance witht he Dynavibe, but I bought and ACES Systems Pro Balancer Sport a couple years ago and have been very happy with it.

http://probalancersport.com/

We have one in our Eaa chapter. Second most used tool in the library behind the sync mate carb synchronizer. Works as advertised. Very easy and somewhat fun to use...

Thanks guys!
It sounds like a good thing to do.
It would be hard to justify a high dollar balancer but at $1500 and if it works just fine, over a few years it should be money well spent.
I think I will order one up!

I have used mine for over 6 years. Balancing Rotax, Subaru, all Continentals and Lycomings, PT-6 and Garretts with 5 bladed prop. Works perfect....

PAMR MX wrote:I love my Dynavibe. I use it on everything from Pilatus pc-12 to super cubs.
I have been using one for a little over three years. I use it about every month and it works just as well as the 10-15k balancers. I rarely need more then three runs to get under .07 IPS and on the turbines i can almost always get .01 or .00 IPS
I have only had one problem with an accelerometer going bad the first year. They replaced it for free.
Really the only difference between this one and an expensive balancer is it does not give a weight solution. It just gives you the vibration (IPS) and the angle location. Its up to you to figure out how much weight to add. The expensive balancers will tell you how much weight to add and compute the changes with later runs. Dynavibes new GX2 will do this but the classic works just fine and is half as much $$$. Having to guess the weight gives you a bit of a challenge on the first run but once you figure out the propeller/ engine combo you can do it much faster on later dates.
You might get a reading of say .1ips and @ 180 degrees. You will have to add weight at 0 degrees to counteract this. You might start out with say 20 Grams of weight. The next run you might get .05 and 180. Its pretty simple math at this point no matter the change to find out how much more weight you need. You then add 40 Grams total weight at 0 degrees and if your lucky you would get .00IPS.
It will take a glare shield thats vibrating up and down to smooth. My cub radio would shake so much it would turn the volume knob up on its own and blast you with full volume 5 minuets later, no more auto volume after. My chieftians would get vibration in the pedals. That is gone. With turbines the change is profound.

Do you have a good way to attach weight to stock Piper backing plates? My balancing experience is limited to big Hartzells on PT6 which is very friendly for mounting weight. I'm concerned about the whimpy material Piper plates are made of. Thanks!

Some of the Lycoming starter gears have holes around the perimeter that work well for adding weight with an AN4 bolt. It doesn't have to go on the spinner back plate. Just make sure the weight does not contact the starter, duh..

Just be sure and debur the hole properly on both sides. Make sure the hole is as close a fit as possible to the bolt. Often times an angle drill has to be used to drill in the required location and if not careful, these are notorious for creating an enlarged hole. Use a large area washer on each side. Chadwick' s "The smooth propeller" is considered the bible. At the propeller repair station I worked at the Faa required us to fill out a form 337 as a major alteration when balancing propellers unless the aircraft maintenance program specifically called for balancing in which case as mentioned above, the backing plates often had if not nut plates at least preinstalled
holes.

Richard

I've got the http://probalancersport.com my self and really like the results. Use it 8-10 times a year -especially when I do a annual or other work. Also do Weight and Balance .

Bought a Dynavibe!

It comes in a small tool case. The case seems a little flimsy but it should work to protect the unit as long as you aren't travelling with it all the time. I haven't had a chance to use it yet. I am several thousand miles from my planes. Next month I will get to try it.

But being as I am near my Tig welder I would like to fab up a mount for the sensors. But I don't know where exactly to mount it on a IO520 and am looking for ideas.

Does anyone have a picture of a mount?