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WWhunter
05-05-2012, 06:28 AM
I just got in my new prop. I have a 3-blade Whirlwind and since this is the very first time I have ever owned or used an adjustable prop, is there any videos or such that show an easy way to set the blade angles?
I got a paddle looking tool with the prop that slides over the blade that I guess you use a laser level or something with. I do have a Warp-Drive protractor in a box I got with the plane.
The WW prop had nothing in the instructions on what angle to start with other than a statement "Adjust pitch setting using the paddle/protractor to 17% from vertical.". Anyone have a suggestion?

mr bill
05-06-2012, 07:31 PM
You have to set the angle while the prop blade being measured is horizontal, then rotate the next blade into position and measure, etc.

You will also need a small digital level, like those sold at Northern Tool or Harbor Freight. Aircraft Spruce sells a very much more expensive version. You set the level on the "shelf" of the tool.

Monocock
05-07-2012, 01:59 AM
Was there not any kind of instructions for pitch setting with the prop?

Without seeing the WW setting tool you have it's difficult to advise. When it slips over the horizontally positioned blade, is there a calibrated angle marker that hangs down with gravity?

As long as you know the static rpm you need, it's best not to get too bogged down in the actual degrees of pitch you are looking for. Pitch degrees are useful as a starting reference point and you should be aiming for a static between 5200 and 5600 rpm (assuming you have a 912 engine). 5200 static will give you a good cruise speed at cruise power and 5600 static will give you the best max take off performance. I have my static set at 5400 so I get a good compromise between climb and cruise speed.

It is important to make sure that the blades are all set at the same pitch to ensure smoothness. It's also important to make sure the blade tracking is within 1/8 inch as if they're not there can be dreadful vibration in the mid-power range.

If you can post a picture of the pitch tool, I'm sure we can give some guidance on how to use it. For what it's worth, I like the sound of the fact that you have got one that slides over the blade as these kind take the pitch at exactly the same position on each blade. Once it is done you will know you have got it exactly right.

mr bill
05-22-2012, 01:51 PM
There is an excellent article about the Whirl Wind prop and how to adjust the blade angles, with pictures in the latest issue of Kitplanes magazine.

WWhunter
05-23-2012, 08:44 AM
Mr. Bill,
I haven't been able to find Kitplanes around here. I don't subscribe because I travel alot and having them forwarded and dealing with change of address is not worth the hassle. I usually pick a copy up when I can find one but being up here in the boonies of MN its a little hard finding one.
I have corresponded many times with the author of the article and have emailed back and forth several times before this article was written. He is a very helpful guy. He told me a while ago he had written an article and I knew it was being published. I think he is going to try and email me a copy.

The instructions that came with the prop leave a LOT to be desired for someone like me who has never dealt with an adjustable prop before. My previous planes have all been certified with fixed pitch props.