What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Digital level for setting prop pitch

AeroDog

Well Known Member
Friend
The KAI says set the blade pitch to within +-0.1 degrees. Most magnetic, cube-type levels which advertise that accuracy (not to be confused with what they can display) only guarantee that accuracy within a degree of 0 or 90 degrees, with accuracy outside that range given as +-0.2 degrees. Can someone recommend a level which can provide the accuracy they're specifying and doesn't cost a fortune? Thanks.

Jerre
 
I've been using a iGaging 9" Digital Level with Magnetic Base and Laser. Seems to work quite nicely and the level is not outrageously expensive.

One nice feature is the level has a 1/4-20 threaded hole on the bottom that I use to attach the level onto the Vans prop pitch tool. I drilled a hole in the pitch tool to secure the level to the prop tool without needing to rely on the somewhat weak magnets on the bottom of the level.
 
The published accuracy on the iGaging 9" Digital Level is .02. The OP wants .01.

I use the cube. I am more interested in repeatability of the level than accuracy of the angle. Repeatability is how I compare one blade to the other, or measure adding / subtracting a degree of pitch to what I currently have set.
 
The published accuracy on the iGaging 9" Digital Level is .02. The OP wants .01.

I use the cube. I am more interested in repeatability of the level than accuracy of the angle. Repeatability is how I compare one blade to the other, or measure adding / subtracting a degree of pitch to what I currently have set.

I show the igaging 9" level to be 0.2, not 0.02 accurate..

With that said I bought this below.. Suppose to be 0.1 accurate, which is what is specified in the Van's KAI's Section 47. I really don't think many would have much luck trying to set something down to .01 of accuracy. Additionally, I'm going to just need to repeat the setting that currently exists. I'm not starting from scratch. If I screw it up and can't get it, I'll just take it and let a pro take care of it.



https://www.amazon.com/gp/product/B071Z7QMX1/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&th=1
 

Attachments

  • 71MqOX3jmCL._SL1500_.jpg
    71MqOX3jmCL._SL1500_.jpg
    148.8 KB · Views: 88
  • Capture.JPG
    Capture.JPG
    101.1 KB · Views: 157
Last edited:
I show the igaging 9" level to be 0.2, not 0.02 accurate..

With that said I bought this below.. Suppose to be 0.1 accurate, which is what is specified in the Van's KAI's Section 47. I really don't think many would have much luck trying to set something down to .01 of accuracy. Additionally, I'm going to just need to repeat the setting that currently exists. I'm not starting from scratch. If I screw it up and can't get it, I'll just take it and let a pro take care of it.



https://www.amazon.com/gp/product/B071Z7QMX1/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&th=1

This is another one of those which lists in the bullet points an accuracy of 0.1 degrees but further down in the fine print says this is for 0 and 90 degrees with the accuracy being 0.2 degrees for other angles. Very misleading. I have a Digi-Pas with these same specs, but it's gone wonky.

Thanks for all the input.

Jerre
 
This is another one of those which lists in the bullet points an accuracy of 0.1 degrees but further down in the fine print says this is for 0 and 90 degrees with the accuracy being 0.2 degrees for other angles. Very misleading. I have a Digi-Pas with these same specs, but it's gone wonky.

Thanks for all the input.

Jerre

Well, hopefully it'll work out. Otherwise, guess I'll use the $18 tool for something around the house or garage that doesn't require it being dead nuts on.. I know I have a couple of golf clubs that need some angle measurements taken. :)
 
Last edited:
Test the square level for repeating measurements. Absolute angle measurements are not necessary. You only need to set both blades the same. I use one of the cheap square ones to set my WW GA prop and it works well.
 
We set ours on the supplied pitch pins and checked with iPhone - perfectly acceptable. Worked for both aeroplanes.

I would strongly suggest a dynamic balance once you have finished testing etc - exhausts and ignitions don't like vibration.
 
I attach a laser to the propeller so that it makes a red line on the floor. Mark the red line with a pencil.
I don't know the number of degrees. But the red line is 100 percent repeatable, much better than any digital level.
A length of wood between the opposite propeller blade and the floor ensures that the prop is always horizontal.
 
I don't know if Van's uses the one shown in the instructions. If they do, I have what appears to be the exact same one, and the specs for it state "±0.1° (level or plumb)". It does not specify an accuracy for when it's not level or plumb.
 
This is by far the best way in my view

This is by far the best way in my view

If the prop is 36" off the floor a .01 pitch off-set is almost 1/4"




I attach a laser to the propeller so that it makes a red line on the floor. Mark the red line with a pencil.
I don't know the number of degrees. But the red line is 100 percent repeatable, much better than any digital level.
A length of wood between the opposite propeller blade and the floor ensures that the prop is always horizontal.
 
Last edited:
As Seagull mentioned in post #4 .... I too feel repeatability is really more important than if the actual true angle is xx.01 or xx.02. The main thing is the final outcome NEEDS to have both prop blades at the EXACT same angle and the digital level of choice needs to display that same desired angle each time the level is placed onto the prop gauge tool.

Many RV-12 owners run the prop blades at different angles than the Van's suggested specification (which is a very good starting point) based on their local conditions for the majority of their flying. Regardless of what angle is chosen, the big thing is both blades need to be the same ... so digital level repeatability is a key factor.
 
Last edited:
We set ours on the supplied pitch pins and checked with iPhone - perfectly acceptable. Worked for both aeroplanes.

I would strongly suggest a dynamic balance once you have finished testing etc - exhausts and ignitions don't like vibration.

I agree, but don't bother with wasting money on a dynamic balance unless you are sure that the angle of your blades are within the recommended tolerance. A very slight mis-match can have a large influence on balance and smoothness.
We don't recommend the use of the pitch adjusting pins. We have found in some cases the blade angles to be off by as much as .7 degrees when they were used.
 
Fine Print

I was more than a bit bummed out when I also read the fine print. The accuracy of the "not cheap" digital angle gauge was +/- .1% only at 0-1, 89-91, and 179-180 degrees, .02% for all other angles. After no luck finding an affordable one with .1% accuracy at the desired angle. I zeroed the gauge on the canopy deck and set the first blade to one of those "other angles" (+/- .2%) then zeroed the digital angle gauge on that blade (+/- .1%). I then used the gauge to zero the other 2 blades giving the recommended accuracy between blades. Seemed to be an acceptable work around.
 
The KAI says set the blade pitch to within +-0.1 degrees. Most magnetic, cube-type levels which advertise that accuracy (not to be confused with what they can display) only guarantee that accuracy within a degree of 0 or 90 degrees, with accuracy outside that range given as +-0.2 degrees. Can someone recommend a level which can provide the accuracy they're specifying and doesn't cost a fortune? Thanks.

Jerre

Most of us used this:

https://www.sears.com/craftsman-digital-torpedo-level/p-00948295000P

Probably a similar one out there... small, magnetic and digital....And of course this is required as well...

https://store.vansaircraft.com/propeller-pitch-bracket-tool-tool-00002.html


Maybe this?

https://www.amazon.com/dp/B07XCDB12...9Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=


You wanted a digital level that was flat and magnetic that would be hands off on the TOOL 0002 while you were holding it on the lip of the prop and letting it settle. Also want to measure each prop in same location..same side...level ground..same distance off ground..level...static RPM is the final judge as I recall.

Us pre-balanced, Catto 3-blade turboprop RV12 pilots don't have to worry about that...;)

I may have an entire set-up soon for sale....Trying decide if I want to sell my 100 hr prop and all the stuff that goes with it....
 
Last edited:
Back
Top