I balanced both my fixed pitch and variable pitch props by trial and error.
I just added a washer to one of the screws that hold the spinner on, and
then ran the engine up through the range. You can feel if the vibration is
better or worse, and by trying the washer in different locations determine
the best position.
Once the best position is found you can then experiment with the
size/quantity of washers to obtain the best results.
I managed to get mine near perfect quite easy, but I still had a small
vibration in the 2 - 3000 rpm band, so I decided to have it dynamically
balanced thinking that would cure it. After spending 120 plus half a day I
came away with a couple of washers fitted in exactly the same place weighing
almost the same as my originals and no significant difference.
Apparently the prop can only be balanced perfectly at one rpm setting, which
would sensibly be the cruise and I had found this by my trial and error
method. The rest of the range is a compromise, but is usually within
acceptable limits. Even the slight vibration I get between 2 - 3000 rpm is
acceptable as it is within a band that is little used.
So its worth having a go at it yourself, it only costs a bit of fuel.
Jim
> Very interested to hear of any budget solution to prop balancing
> Balancing a in-flight variable is
> usually more difficult as its difficult to mount them on a balancer with
> sufficient accuracy.
> I understand Noel Trigg in the UK uses a lap top and his own software to
> balance props. I have not heard anything other than good about the results
> he achieves but he is not cheap at around 300 pounds a pop. Anybody with
> good/bad results from other balancers in the UK would be useful
infromation.
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