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Sensenich Prop Adjustment...

Tony_T

Well Known Member
Patron
The plans say to set the prop pitch full on the initial installation. I followed this instruction, but after torqueing the bolts I referred again to the hub index marks and it looked like they had moved a little. I let it go. My static rpm was 5200, and the first test card indicated that I had ferocious take off and climb (for 83 cubic inches), but was only seeing 102 knots in level flight at 5500 RPM, with enough throttle left to overspeed the engine. My prop was definitely underpitched.
I contacted Van's for more advice on pitching the prop, and found out that Scott will have an in-depth article in the next RVator of their experience with this prop and how to adjust it. Scott also made a fixture of scrap alum angle that contacts the trailing edge and back of the blade and then uses a digital level to measure the blade angle.
I took Scott's idea and modified it a bit to come up with my version of the MPPF (McDaniels Prop Protractor Fixture). This little fixture contacts the trailing edge of the blade and the back of the blade in 3 places and uses Scott's sighting notch to line up with the paint strip on the front of the blade.
Scott, I hope you don't mind me going on like this about your idea, but it really is a good one.
[url=http://tonytessitore.smugmug.com/RV-12-Project-N577RV/RV-12-Tools-Work-Fixtures/7992519_GYr3k#910442110_Yp9n6-A-LB][/URL]

I found a nice little digital level on the internet for $24.99 and it even has a tripod screw attachment so I could bolt it to the MPPF:
[url=http://tonytessitore.smugmug.com/RV-12-Project-N577RV/RV-12-Tools-Work-Fixtures/7992519_GYr3k#912340962_fMNUT-A-LB][/URL]

Here is the protractor in use:
[url=http://tonytessitore.smugmug.com/RV-12-Project-N577RV/RV-12-Tools-Work-Fixtures/7992519_GYr3k#913401658_rpfgo-A-LB][/URL]

I found the device to be repeatable to about 0.1°. And, I found my blades to be 1° different from each other! That is way too much. The Sensenich instructions say to set the blades within 0.25° of each other if you have a protractor. I was able to readjust the pitch and set the blades to within about 0.1° of each other.
I am now getting 115 knots at 5360 (without pants), and the engine will not pull more RPM in level flight, so I may be slightly over pitched. I think I will leave it this way for a while until I get more time on the motor, then make a final adjustment.

So, it looks like that small amount of adjustment we are restricted to by the stops in the hub are ideal for this aircraft. But, the hub index marks are rather crude and you need a protractor to do the job well.

Thanks Scott, for your great idea, and I am sure everyone will be looking forward to the next RVator.

Tony
 
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Good Job

Awesome Tony! What is your static WOT now? I have mine at 4900 but that simply by lots of trial and error...I like your idea better. Plus I didn't know the blades could be different angles...I thought when you move one, the other moves as well. How do you alter that? Thanks.
 
Awesome Tony! What is your static WOT now? I have mine at 4900 but that simply by lots of trial and error...I like your idea better. Plus I didn't know the blades could be different angles...I thought when you move one, the other moves as well. How do you alter that? Thanks.

It is true if you move one blade the other will also move but if you depend on that, the blade pitch can easily be one degree different, blade to blade. You have to use a protractor or Scott's/Tony's fixture and a digital level. Great idea!!
 
Awesome Tony! What is your static WOT now? I have mine at 4900 but that simply by lots of trial and error...I like your idea better. Plus I didn't know the blades could be different angles...I thought when you move one, the other moves as well. How do you alter that? Thanks.

My static RPM was 4900 but there was some wind blowing at the run-up area, so it may actually be less. I am going to adjust to produce airspeeds anyway, I would like to have a fast cruise close to the 120 knot limit (with pants) and a comfortable cruise at about 100-105 knots about 4900 RPM.

Like Marty says, there is enough play in the hub system that the blades can be 1? different from each other even though they are designed to move together.

Make the protractor. There are commercial ones to consider, but this one works and, for me, making stuff is what "experimental" is about ;).

Tony
 
Prop Adjustment

I followed Your lead and bought the Sears Craftsmen Digital Torpedo level and set it up in a similar method and found my prop off .8 Degrees between the two blades. After a fine tune adjustment I cant say for sure I am going faster but it does seem like the engine is running much smoother.

http://www.sears.com/shc/s/p_10153_12605_00948295000P

John
RV12 N1212K
 
prop adjustment

We loosened the prop adjustment, strapped a laser pointer on the blade, rotated the blade to each end of its extreme and made a mark on the ground at each extreme point. Then we divided the distance on the ground into even increments and made an appropriate adjustment. We repeated the measurement for the other blade.
Meade and George
N612RV
 
Packing Crate Prop Protractor

Packing crate Prop Protractor

I made a prop protractor out of scrap wood from the packing crate. The protractor touches the prop at two points. If you want to be technical, it is actually 3 points if you count the left and right ends of the little 2" square piece of plywood fastened to the bottom of the 2x2. Fastening the plywood with one screw will allow the plywood to be rotated to align with the prop. The forward end of the 2x2 should be slightly heavier than the aft end in order to keep the vertical 2x2 in contact with the prop. A piece of painter's tape located 22.5 inches from each prop end serves as a left - right alignment indicator for the protractor. The end of the prop needs to be exactly the same distance from the floor every time the pitch angle is measured. Even though I filed away the vertical 2x2, it is not necessary to make it curved. Straight is OK. I filed it because I fastened the vertical 2x2 too close to the prop. The relative pitch is measured with a ruler from the oil tank up to the 2x2. The actual angle of pitch is not known. But it is easy to measure (in distance) the span from course to fine pitch and to measure difference, if any, between the two blades. The object is to have both blades pitched at exactly the same angle, whatever it is. As long as the distance between the oil tank and the 2x2 remains the same for both blades and is repeatable each time the prop is rotated 180 degrees, then it must be accurate. No matter how the pitch is measured, the results must be repeatable to assure accuracy. The distance from the prop to the oil tank is about 24 inches. A small change of pitch results in a big change in distance between the oil tank and the 2x2. That is what gives the packing-crate-prop-protractor a high resolution. A 1/32" measurement error at the oil tank translates into 0.075 degree pitch error. If a builder prefers a laser level, he could still make a similar wooden bracket to hold the level. The laser level could either sit on top and be aimed at the wall or be fastened to the vertical side and be aimed at the floor.
I temporarily replaced the nord-lock washers with hardware store washers while adjusting the prop. That allowed me to tighten and loosen the bolts several times without fear of wearing out the bevels on the nord-lock washers. After I was satisfied with the pitch angle, I loosened one bolt at a time and put the nord-lock washers back in.
Joe
Update 11-7-2011 The packing crate protractor is NOT very accurate. I now use a laser level aimed at the floor.
See Picture:
Prop%20Protractor.jpg
 
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Thanks Marty

Thanks Marty, I will pay you next time I see you. :D
Now you know why it is taking me so long to build the RV-12. I spend too much time thinking and not enough time building. But hey, I am having fun along the way. Sometimes the journey is just as much fun as the destination.
Joe
 
Protractor

I made one using the suggest materials and it works great. The blades are within 0.1 degrees.

I went to the talk that Phil Lockwood have at OSH. We attended and lots of good information. The question came up about take off RPM. The rotax manual says 5200 minimum but it sounded like that may be application dependent. Lockwood said that "4900 in climb" would be good. I am still a little fuzzy on what we should be seeing. I recall in an earlier thread that Scott suggested static RPM of 4950. At least that is what I recall. If we set that as static RPM what take off RPM will we be seeing. What climb RPM? Phil Lockwood seemed to suggest that 4900 would be better and would have the engine running cooler.

It does seem that the RPM we see on take off is somewhat dependent on ambient temp and density altitude. Is that true? Should we re-adjust the prop seasonally?

Some guidance from the mothership (Scott) would be very helpful.

Richard
 
I went to the talk that Phil Lockwood have at OSH. We attended and lots of good information. The question came up about take off RPM. The rotax manual says 5200 minimum but it sounded like that may be application dependent. Lockwood said that "4900 in climb" would be good. I am still a little fuzzy on what we should be seeing. I recall in an earlier thread that Scott suggested static RPM of 4950. At least that is what I recall. If we set that as static RPM what take off RPM will we be seeing. What climb RPM? Phil Lockwood seemed to suggest that 4900 would be better and would have the engine running cooler.

The recommendation in the PAP of a static RPM of 4950 to 5000 for first flight is still correct. This will give good performance as builders learn the airplane.
The actual setting used is airframe dependant so I think Phil was using that as a general guide line. Phil is correct, that operating at higher RPM's does result in higher oil temps.

My opinion is that the best all around RV-12 setting is one that gives you about 5100 RPM when climbing at Vy (best rate, 75 Kts) right after takeoff from your home airport. It also gets you close to the 5200 RPM Rotax recommended minimum (which in reality isn't practical for anything other than slower / high drag airframes)
This will result in good takeoff and climb performance and pretty good cruise down low. In level flight at lower altitudes (1000 - 4000 ft) you will have to throttle back to about 24 - 25 inches Mp to stay below 5500 RPM. As you climb to higher altitudes you have throttle to add (because you have to throttle back down low). This will result in very good true airspeeds up high (7500 ft and above). It also keeps the takeoff performance maximized if landings are made at higher elevation airports.
If you plan to do very little cross country flying at higher altitudes, then you would probably want to set up for a Vy climb in the 4900 - 5000 RPM range this would give you a little better speeds at lower altitudes but with a sacrifice in takeoff and climb performance.

N412RV is currently set up for about 5120 RPM, climbing at Vy from Aurora airport (ground elevation 200 ft MSL). This setting was perfect for the trip it just made to OSH and back. It has very good cruise performance at higher altitudes but still very good takeoff performance in high density altitudes that are common with the East-West route we have to fly over the Rocky Mountains (airports with ground elevations of 5500 ft or higher are very common).

It does seem that the RPM we see on take off is somewhat dependent on ambient temp and density altitude. Is that true? Should we re-adjust the prop seasonally?

This will always be the case with a non turbo normalized engine. It is even more noticeable with a fixed pitch propeller. It is also the reason I think the best setting is one that requires the pilot to throttle back somewhat at low altitudes. This leaves you some reserve for when at higher altitudes or when it is hot and the density altitude is much higher than typical.

Should we re-adjust the prop seasonally?

That depends on what part of the country you are flying in. In places where the temp is much more constant year around (like Aurora, Oregon) it is not of as much value (but still valuable if you are looking for the best performance possible in a very specific altitude range).
In places where there is a much bigger temp differential between summer and winter it could probably be very beneficial.
That is a main reason the ground adjustable was chosen as the standard for the RV-12...it can be optimized for what ever a particular owner needs (we don't all want to climb to 10K ft and we don't all operate in temps below 0 deg C.

I hope this helps....
 
correlation between degrees of pitch and rpm

I am currently conducting flight tests and have discovered that I am over pitched. I have a static RPM of 4900. In climb at 75 kts, 70 degrees, field elevation 15', I only get 4950 or so RPM. WOT at 3000' is 5300 RPM. Has anyone come up with a correlation between pitch change and RPM? Rather than make an arbitrary change in pitch and see if its right, it would be nice to know .1 degree = X number of RPM. Thanks
 
I am currently conducting flight tests and have discovered that I am over pitched. I have a static RPM of 4900. In climb at 75 kts, 70 degrees, field elevation 15', I only get 4950 or so RPM. WOT at 3000' is 5300 RPM. Has anyone come up with a correlation between pitch change and RPM? Rather than make an arbitrary change in pitch and see if its right, it would be nice to know .1 degree = X number of RPM. Thanks

I can't give you a specific correlation, but I suggest you consider reducing the pitch by about 0.3 degrees and fly again in the same conditions. Use the amount of RPM change to decide how much more (if any) you change pitch on the last adjustment.

Keep in mind that if you have not yet set the pitch the blades using a protractor, if you find them not the same, just adjusting them to match will change RPM some (depending on how large the mismatch was).
 
Thanks Scott. I did use the nifty tool and a digital level and was able to get the blades within .1 degree of each other. This method is so much better than the Warp drive protractor or the indexing hub on the propeller. I'll try .3 and see how it goes.
 
Pitch and resulting RPM

I fitted my white-colored blades yesterday - I guess I should have put a smiley on my previous spelling of colour ;-), it was certainly meant in jest.

Using a tool similar to Tony's I set my blades to 23 degrees (aligned on the edge of the stripe closest to the hub), and found this was much too coarse. I could only get 4550 static rpm. I readjusted to 22 degrees and got 4750 static rpm. This translated to a maximum 5500 rpm full throttle at 1500 feet. Straight-and-level in smooth air, and with no wind, the Dynon was indicating 125 knots.

This is still overpitched, so next time I'll probably try 21 degrees, on the assumption that, for me at least, 1 degree equates to 200 rpm.

My digital level was the "Clinometer" app on my iPhone which seemed to work fine.

Cheers...Keith
 
The plans say to set the prop pitch full on the initial installation. I followed this instruction, but after torqueing the bolts I referred again to the hub index marks and it looked like they had moved a little. I let it go. My static rpm was 5200, and the first test card indicated that I had ferocious take off and climb (for 83 cubic inches), but was only seeing 102 knots in level flight at 5500 RPM, with enough throttle left to overspeed the engine. My prop was definitely underpitched.
I contacted Van's for more advice on pitching the prop, and found out that Scott will have an in-depth article in the next RVator of their experience with this prop and how to adjust it. Scott also made a fixture of scrap alum angle that contacts the trailing edge and back of the blade and then uses a digital level to measure the blade angle.
I took Scott's idea and modified it a bit to come up with my version of the MPPF (McDaniels Prop Protractor Fixture). This little fixture contacts the trailing edge of the blade and the back of the blade in 3 places and uses Scott's sighting notch to line up with the paint strip on the front of the blade.
Scott, I hope you don't mind me going on like this about your idea, but it really is a good one.
[url=http://tonytessitore.smugmug.com/RV-12-Project-N577RV/RV-12-Tools-Work-Fixtures/7992519_GYr3k#910442110_Yp9n6-A-LB][/URL]

I found a nice little digital level on the internet for $24.99 and it even has a tripod screw attachment so I could bolt it to the MPPF:
[url=http://tonytessitore.smugmug.com/RV-12-Project-N577RV/RV-12-Tools-Work-Fixtures/7992519_GYr3k#912340962_fMNUT-A-LB][/URL]

Here is the protractor in use:
[url=http://tonytessitore.smugmug.com/RV-12-Project-N577RV/RV-12-Tools-Work-Fixtures/7992519_GYr3k#913401658_rpfgo-A-LB][/URL]

I found the device to be repeatable to about 0.1?. And, I found my blades to be 1? different from each other! That is way too much. The Sensenich instructions say to set the blades within 0.25? of each other if you have a protractor. I was able to readjust the pitch and set the blades to within about 0.1? of each other.
I am now getting 115 knots at 5360 (without pants), and the engine will not pull more RPM in level flight, so I may be slightly over pitched. I think I will leave it this way for a while until I get more time on the motor, then make a final adjustment.

So, it looks like that small amount of adjustment we are restricted to by the stops in the hub are ideal for this aircraft. But, the hub index marks are rather crude and you need a protractor to do the job well.

Thanks Scott, for your great idea, and I am sure everyone will be looking forward to the next RVator.

Tony

Guess I need to build one of those out of some aluminum L channel scrap I have laying around.
 
Guess I need to build one of those out of some aluminum L channel scrap I have laying around.

Or you could purchase the premade one available from Van's.
This would also enable you to use specific degree values that are specified in the KAI and PAP (the values correlate to a specific tool)
 
Or you could purchase the premade one available from Van's.
This would also enable you to use specific degree values that are specified in the KAI and PAP (the values correlate to a specific tool)

I am already on the hook for a new enrichment cable assy from Van's. I've bought and changed out many a stranded cable and housing on my mountain bikes. Buying the whole Assy is a bit of a shocker.

Seems someone didn't bother to leave either an inch, or crimp a lead bullet cap on the end to prevent stranding of the cable as called out in section 50-1 of the KAI.

The lock nut wasn't even butted tight up against the stop, and the unit was completely un threaded, out of even having any adjustment, to get some enrichment on the right Bing Carb.

Baby steps, Scott, baby steps, I still have to pay an instructor for lessons, too. :D
 
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When replacing enrichment cable, you need to safety wire the end of the sheath where it enters the sweeping elbow at the carb. Because the cable gets so slack when enricher is shut off the sheath can back out of the cup on the elbow and then prevent full motion of the cable. Thin safety wire works best in this application.

 
When replacing enrichment cable, you need to safety wire the end of the sheath where it enters the sweeping elbow at the carb. Because the cable gets so slack when enricher is shut off the sheath can back out of the cup on the elbow and then prevent full motion of the cable. Thin safety wire works best in this application.


Noted, also going to witness paint those nuts on the shaft of the Carb throttle and enrichment devices.

A good example of where a picture is worth 1000 words. I am a much better visual learner, than written.
 
When replacing enrichment cable, you need to safety wire the end of the sheath where it enters the sweeping elbow at the carb. Because the cable gets so slack when enricher is shut off the sheath can back out of the cup on the elbow and then prevent full motion of the cable. Thin safety wire works best in this application.


I can see why it would be needed in the installation shown in the photo.
There is too much slack in the cable so the cable housing would easily come out of the barrel adjuster.

I have never seen the housing come out of the barrel if the cables are adjusted properly.
 
I can see why it would be needed in the installation shown in the photo.
There is too much slack in the cable so the cable housing would easily come out of the barrel adjuster.

I have never seen the housing come out of the barrel if the cables are adjusted properly.

I would sooner leave a little slack in the cable, and tie off with safety wire, than cinch it tight, have in excess of 1 inch of cable coming out of the clamp, and then cutting the excess end off of the cable and fraying it to bits, and the cable starts slipping, due to fraying.

Which is what the previous owner has put me in, position wise. A very expensive mistake, over something very, very simple, even a repair technician in a bicycle shop knows this. Put heat shrink on those ends, or a lead cap you can crimp on, everyone!

I don't know if Van's sells the cables with crimp on lead caps, if they don't, the prebuilt cables should come with those items in the cable kit.
 
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I think best to leave this cable with extra slack. The return spring for the enricher arm is very weak. You don't want to have enricher circuit happening during normal ops. Safety wire the sheath / elbow and you'll be fine.
 
Back to adjusting the prop

The 2012 I bought had a prop set up for cruising. It does have the 2018 upgraded hub version from Sensenich recorded in the logs as being replaced.

It has a very poor climb rate at 1000 ft ASL.

Read the Sensenich prop manual that came with the plane, as shown here.

http://www.sensenich.com/wp-content..._2_Blade_RotaxJab_Instructions_1314811785.pdf



Today, we tried to adjust the prop pitch. I have a thin almost mahogany panel looking wooden device from Sensenich that looks like it's for setting the pitch.

I also have a device (that the owner of 836BL who built a 2015 RV-12) says is a Van's pitch setting device. We are both dumbfounded on how it even works, whether the hook side goes on the leading edge or the trailing edge when the prop is level, does it sit flush, or do you pull it out so that the hook portion is tight.

Need help here, very, very frustrated, 1/2 day wasted with nothing accomplished.

The 2012 version has a plastic insert around the pitot tube with dowling pin guidance? See page 5 on link above, so that both props are within a half a degree of each other? Really Sensinich or Van's? I thought we had these down to 71.2 degrees pitch and within 0.1 degree pitch of each other?

If anyone can point me to instructions on how to use the metal Van's prop pitch gauge with an electronic level, I'd be very grateful to pay it forward. So much has changed between 2012 and 2020 on these planes, such that sometimes I feel my brain capacity is the experiment, not the plane.

When I look here on 47-07, at figure 4 picture, the tool appears to be hanging on the front edge of the prop in the picture, with the level measuring the pitch across the back side of the propeller, touching the tab of the gauge?


Yet figure 5 shows that the gauge is hanging off of the back side of the blade? So which is correct?

https://www.vansaircraft.com/wp-content/uploads/2019/01/Section_47.pdf
 
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There are many ways to measure the pitch angle of an adjustable prop blade.
Sensench supplies that (crude in my opinion) tool in the box with every new propeller. I don't know of anyone that uses it.

My recommendation is still that you get the Van's tool and use the KAI instructions (they show how to use the tool). Easy peasy.... You have a written procedure always at your finger tips if you forgot from the last time you did it, and you don't even have to ask on VAF and hope to get a correct answer in a reasonable amount of time ;)

Note that on 47-07 figure 4, there is no white paint on the tip of the blade..... the view is looking at the back side.
 
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I would sooner leave a little slack in the cable, and tie off with safety wire, than cinch it tight, have in excess of 1 inch of cable coming out of the clamp, and then cutting the excess end off of the cable and fraying it to bits, and the cable starts slipping, due to fraying.

Which is what the previous owner has put me in, position wise. A very expensive mistake, over something very, very simple, even a repair technician in a bicycle shop knows this. Put heat shrink on those ends, or a lead cap you can crimp on, everyone!

I don't know if Van's sells the cables with crimp on lead caps, if they don't, the prebuilt cables should come with those items in the cable kit.

I think best to leave this cable with extra slack. The return spring for the enricher arm is very weak. You don't want to have enricher circuit happening during normal ops. Safety wire the sheath / elbow and you'll be fine.

That is more than just a little slack.
It is far more important for the two sides to be in sync with each other. With that much slack it makes it much more difficult to do that.

All that is needed is just enough slack to allow the cable to be wiggled very slightly when the enrichment control is fully turned off.
 
There are many ways to measure the pitch angle of an adjustable prop blade.
Sensench supplies that (crude in my opinion) tool in the box with every new propeller. I don't know of anyone that uses it.

My recommendation is still that you get the Van's tool and use the KAI instructions (they show how to use the tool). Easy peasy.... You have a written procedure always at your finger tips if you forgot from the last time you did it, and you don't even have to ask on VAF and hope to get a correct answer in a reasonable amount of time ;)

Note that on 47-07 figure 4, there is no white paint on the tip of the blade..... the view is looking at the back side.

We HAVE the Van's tool.... please look at figure 4 on 47-07, what is the level measuring in that photo? Is the level on the front side of the prop, or the back side of the prop in that photo, with a reading of 71.4 degrees? Is tool 0002 with most of the metal on the front side or the back side of the propeller? What does the picture show?

What I am asking is this: is the written step 4 correct, or is the photograph of step 4 correct? Only one of them can be right. Both show the level on the back side of the prop. The photo in figure 4 show the gauge 0002 hanging on the trailing edge, with most of the metal on the gauge on the front side of the propeller, while the level is
taking a measurement off of the BACK side of the propeller.

The written instructions says it differently.

I want to understand that we do NOT use the magnetic feature of the steel in Tool 0002 with the magnetic feature of the digital level? The level never goes against the whole steel plate when taking the angle of measurement, is that correct? The magnetic level only touches the aft blade surface and the extended tab of the tool?

I'm having a reading comprehension problem here, Scott.
 
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Sensenich Prop Adjustment

As some else said, follow the instructions in the KAI. But here is a practical tip I got from someone on this forum. Buy two small digital levels. Then when you level the prop, you can leave that level in place as you adjust the blade angle. That way when you are making the adjustment, you can glance back at the other level and know it is level when making the adjustment. I have done it with one level and two levels, and it is much easier with two levels. And the levels only cost about $30.00 if my memory is correct.
 
We HAVE the Van's tool.... please look at figure 4 on 47-07, what is the level measuring in that photo? Is the level on the front side of the prop, or the back side of the prop in that photo, with a reading of 71.4 degrees? Is tool 0002 with most of the metal on the front side or the back side of the propeller? What does the picture show?

What I am asking is this: is the written step 4 correct, or is the photograph of step 4 correct? Only one of them can be right. Both show the level on the back side of the prop. The photo in figure 4 show the gauge 0002 hanging on the trailing edge, with most of the metal on the gauge on the front side of the propeller, while the level is
taking a measurement off of the BACK side of the propeller.

The written instructions says it differently.

I want to understand that we do NOT use the magnetic feature of the steel in Tool 0002 with the magnetic feature of the digital level? The level never goes against the whole steel plate when taking the angle of measurement, is that correct? The magnetic level only touches the aft blade surface and the extended tab of the tool?

I'm having a reading comprehension problem here, Scott.

Look closely at Fig 4 again. Note the the entire blade is black (no white tip paint)
so the view of the blade in that photo has to be looking at it from the back side.

The photos in Figure 5 and Figure 4 were both taken without moving anything. Your eyes are being fooled on Figure 4 because it is a fwd looking view and the digital level is covering/hiding most of the tool.
 
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As some else said, follow the instructions in the KAI. But here is a practical tip I got from someone on this forum. Buy two small digital levels. Then when you level the prop, you can leave that level in place as you adjust the blade angle. That way when you are making the adjustment, you can glance back at the other level and know it is level when making the adjustment. I have done it with one level and two levels, and it is much easier with two levels. And the levels only cost about $30.00 if my memory is correct.

Actually I use a 9" Torpedo bubble level on the prop hub. Make sure wood blocks are identical and mark Front/Back/L/R so you can repeat the setup. Also flip bubble level around to check accuracy of bubble.

Digital level is used for setting pitch of blades. Because it is used only for blade pitch you only have to zero once on canopy rail. Use Van's sheetmetal gauge - it works great...
 
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Actually I use a 9" Torpedo bubble level on the prop hub. Make sure wood blocks are identical and mark Front/Back/L/R so you can repeat the setup. Also flip bubble level around to check accuracy of bubble.

Digital level is used for setting pitch of blades. Because it is used only for blade pitch you only have to zero once on canopy rail. Use Van's sheetmetal gauge - it works great...


We are using the Van's stamping. Something is not working great, beginning to think it's the digital level that is on the fritz. Had to change out the AAA batteries in it, one of them leaked, and there was some corrosion on the terminals.

Edit: Went back out to the hangar this evening... Friend who has done this numerous times before set the jig on the wrong split of black and white, one inch closer to the hub... tried it on outside line 3 Inches from the tip... and the measurement is looking much, much better with the jig.

I am thinking of wedging a small piece of foam between the jig and the back side of the prop, to retain the jig in place without having to hold it there with my index finger.

Magnets on the Husky brand digital level are not strong enough to hold the level to the steel Van's jig without slipping, so I ordered a digital level with neodynium magnets for some more oomph of stick 'um to the jig.
 
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Use digital level with a mounting hole on the bottom

The Van's TOOL-00002 has a rather small surface area for the magnets on the bottom of a level to get a stable grip.

My digital level has a threaded tripod mounting hole on the bottom, so I drilled a single 1/4" hole into the TOOL-00002 pitch tool so the digital level can be attached to the pitch tool without relying on the anemic magnets on the bottom of the level ... as can be seen in the photo in the link below.

https://2.bp.blogspot.com/-omZdN-nmEQg/V284dCsbqWI/AAAAAAAAMCk/JeHNmBuSnOcN8hJpll6p2EI-QLG6eszxACLcB/s1600/DSC02077.JPG

If your digital level has a threaded hole on the bottom, use it. Works great!
 
Regarding the prop adjust tool...

Folks, please note that my original post to start this thread was 10 years ago!

Since that time the technique for adjusting the prop has matured and the tool that Van's now supplies with the kits works better than my original tool. The procedure has also matured by referencing the prop pitch to the cockpit rail.

I have recently had inquiries about making my tool. I recommend using the Van's tool. My tool was aluminum so magnets would not hold it. Not all levels have the tripod mounting threaded hole.

The Van's tool is steel. Some short digital levels have stronger magnets on the bottom than others. When shopping for a level to use with the tool-00002 take the tool with you and check the strength of the level magnet.
 
Folks, please note that my original post to start this thread was 10 years ago!

Since that time the technique for adjusting the prop has matured and the tool that Van's now supplies with the kits works better than my original tool. The procedure has also matured by referencing the prop pitch to the cockpit rail.

I have recently had inquiries about making my tool. I recommend using the Van's tool. My tool was aluminum so magnets would not hold it. Not all levels have the tripod mounting threaded hole.

The Van's tool is steel. Some short digital levels have stronger magnets on the bottom than others. When shopping for a level to use with the tool-00002 take the tool with you and check the strength of the level magnet.

My builders KAI from 2010 for 120212 isn't the most recent or current version, hence the search here.
 
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