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View Full Version : Measuring Rake



Mark75H
02-23-2009, 03:13 PM
I know how to measure pitch with a wedge of card stock ... can I measure rake the same way?

jetpack
03-11-2009, 03:15 AM
Hi Mark,

You mentioned measuring pitch with a piece of cardstock. How do you go about doing this? I never heard how to do this before. Are you using it to check the face or the back of the prop?

I've seen pitch gages before and know how they are used to come down and touch the cup as it is indexed but thats about all.

David

Hottrucks
03-11-2009, 06:20 AM
yes you can I'm not sure how your doing either but as you know rake is at the hub...depending on the prop but on a o/b prop be sure to come off the hub about 1/2" to get a good #

I don't know how often you woud use it but if you like I can check on a price of one for you they arn't that expencive to purchace

Mark75H
03-11-2009, 08:04 PM
You mentioned measuring pitch with a piece of cardstock. How do you go about doing this? I never heard how to do this before. Are you using it to check the face or the back of the prop?


It was a variation of this:http://www.propellerpages.com/?c=articles&f=2006-03-27_manual_pitch_measurement

I think Ed Hatch, Tom Brockmeyer or someone else on one of the old Merc discussion boards found it. I can't find my notes related to it, but it works as well as anything for comparing different props all on the same table at the same time. You can easily line them up by pitch even if you don't know the exact pitch ... and if you have the software part you can make a fair calculation/estimate of the pitch.

I know how to mechanically compare pitch, now I want to know how to compare rake on 2 props side by side.