Adjusting prop pitch.

[buster]

I went in to Sears tool dept. today and picked up a 7" digital torpedo level. Someone over on the SA forum recommended it for adjusting the prop pitch.

I'm sure I could have gotten the job done without that fancy of a gadget, but when I saw it the first time, thirty five bucks actually started burning right through my pocket. I think I got to the store just in time

Anyway I haven't bought any shiny new tools in a while, and I sure don't want to get out of the habit

If anyone is interested, the model no. is - 48295

Dave

[Duane Scarborough]

Buster,

I agree with you 1,000 % on this. Digital levels are the cat's pajamas. I picked one up on sale at Sears right before Christmas, and I don't know how I've got along without one for so long.

Mine is a Craftsman 48292. I bought it so I'd have it for setting prop pitch, but it's been really handy for other things too.

It's supposed to be accurate to 0.1 degree, and it is. I took it to work and compared it against a high dollar precision level in the machine shop. It's right on the money.

0.1 degree accuracy is plenty good enough for me.

Everyone deserves to buy one of them for them self.

Duane

[buster]

After some experimenting with the level, I found it works well to attach it to the prop with a rubber band. That way I can concentrate on setting pitch and not holding the level in place.

I heard that the place to check pitch is about 70% out from the root. Is that the best place?

It seems to me that it may depend on the twist of each particular prop since their are different designs.

Dave

[Duane Scarborough]

Buster,

70% out is what I've read in a couple of places. Any time you compare numbers, make sure that you're both talking about measuring it the same way, and in the same location.

If you're not comparing it against someone Else's numbers, it isn't quiet as important, but it is important that you do it the same each time, so that the numbers mean something to you.

Since the 70% out seems to be a common way, I'd lean toward doing it that way.

Now, the question is 70% out from where. You're saying root of the blade, but I seem to remember that it was 70% out from the center.

I'll see if I can find a reference...

Comparing numbers would only make sense if you're comparing numbers for exactly the same prop. And same reduction, etc. I think it'd be a waste of effort otherwise.

Duane

[chuckitt]

We do it at the tip of the blade, that way we don't have to measure all the blades and count on getting the mark at the same place on each blade. We don't care how many degrees it is as long as we have them all the same and we have enough pitch to hold the max rpm where we want it. Your prop is your engine governor.
Thanks, Chuck

[buster]

Well it looks like I've been doing it right then

Thanks Chuck and Duane.

Dave