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Nicest Prop Pitch Fixture?

Threetracker

Active Member
I believe I have seen four or five nice propeller fixtures made for use with a digital level in setting the ground adjustable Sensenich composite propeller. I think it's time that we take a good look at who has the best little design and put together a 'package' that could be made available at $50-$75 that would make everyones life better that maintains an RV-12.

I see lots of 9" digital levels out there at Sears and Home Depot and they all proclaim a level of accuracy within .1 degree and a selling price of $39.95. A simple fixture and a worthy digital level would make a nice package for any RV-12 owner/operator.

Sure, I can build a fixture for my use and I'm pretty sure that someone at Vans has built a fixture that is used on the company demo unit; but I haven't seen a fixture offered to the RV-12 public?

Anybody interested?

Jay Sluiter
N124CS
Albany, OR (S12)
 
Nothing can set the blades closer to each other than to point a laser lite to a spot on the floor.
 
Prop Pitch adjustment instructions

Rvator issue Number 3 for 2010, has an in-depth article by Scott on using the protractor. If you don't have it, just click on the picture, go to page 3.




Tony
 
I believe I have seen four or five nice propeller fixtures made for use with a digital level in setting the ground adjustable Sensenich composite propeller. I think it's time that we take a good look at who has the best little design and put together a 'package' that could be made available at $50-$75 that would make everyones life better that maintains an RV-12.

I see lots of 9" digital levels out there at Sears and Home Depot and they all proclaim a level of accuracy within .1 degree and a selling price of $39.95. A simple fixture and a worthy digital level would make a nice package for any RV-12 owner/operator.

Sure, I can build a fixture for my use and I'm pretty sure that someone at Vans has built a fixture that is used on the company demo unit; but I haven't seen a fixture offered to the RV-12 public?

Anybody interested?

Jay Sluiter
N124CS
Albany, OR (S12)

For pitch adjustments I use vans fixture and a digital level per KAi and note the bubble is off a third to the right when looking straight-on, even after leveled on canopy frame, and reading 0.0. Any ideas why the difference? Woodblocks are squared. The digital level reads .08-9 when bubble appears centered.
 
For pitch adjustments I use vans fixture and a digital level per KAi and note the bubble is off a third to the right when looking straight-on, even after leveled on canopy frame, and reading 0.0. Any ideas why the difference? Woodblocks are squared. The digital level reads .08-9 when bubble appears centered.

I also use Van's fixture and haven't had any trouble setting my pitch but I can't visualize the two measurements you're referring to when you say there's a difference.

My digital level has both a bubble and a digital readout. Are you saying the bubble and digital readout on your level don't agree?
 
I also use Van's fixture and haven't had any trouble setting my pitch but I can't visualize the two measurements you're referring to when you say there's a difference.

My digital level has both a bubble and a digital readout. Are you saying the bubble and digital readout on your level don't agree?

Hi Tom, Yes. Bubble is off to the right when calibrated/digital reads 0.0. How can that be?
 
You may need to check the calibration of your bubble level. A web search for ?how to calibrate a spirit level? should return several written and video procedures. If your level is out of calibration and Unless your level is a expensive engineers machinists level you will probably just want to replace it.

-larosta
 
Level

Set the level on any close to level surface and mark the location of the level.
Rotate the level 90? in the same location and the bubble should be in the exact location it was in the first test, if it is the level is ok.

A easy test the level hold the level on the wall with the bubble between the lines then draw a line on the wall.
Rotate the level 90? and check the line, if it is not level then draw a new line with one end on the first line.
Level is a line in the center of the distance between the two lines drawn.
A good idea if you are married put a piece of paper or removable tape on the wall first.

Joe Dallas

You may need to check the calibration of your bubble level. A web search for ?how to calibrate a spirit level? should return several written and video procedures. If your level is out of calibration and Unless your level is a expensive engineers machinists level you will probably just want to replace it.

-larosta
 
Hi Tom, Yes. Bubble is off to the right when calibrated/digital reads 0.0. How can that be?

Is the bubble an actual spirit level? My digital level has a bubble but it's just an electronic picture of the digital readout, not a spirit level that's independent of the digital value. If my bubble was different than the digital readout I'd figure it was defective.
 
Hi Tom, Yes. Bubble is off to the right when calibrated/digital reads 0.0. How can that be?

Most digital levels have a calibration function.
If your bubble turns out to be accurate but the digital value is not, perhaps you accidentally recalibrated when it wasn?t actually level.
 
Most digital levels have a calibration function.
If your bubble turns out to be accurate but the digital value is not, perhaps you accidentally recalibrated when it wasn?t actually level.

Scott,
I?m fairly confident I have her set at 71.4 w/i .1.

Say, is it possible at 71.4 to get a high MP alert on climb out and it goes away at initial cruise?

Thanks,
Doug
 
Any info/historical facts on Effects of high MAP an ROTAX 912s

The few in our fleet do this regularly.

With respect to MAP, I know what overboosting an C/S prop?d engine is and what it can lead to rather quickly. Any stories out there about effects on fixed pitched ROTAXs? Any more info out there other than it should be avoided..? If 27.5? is high on the meter, then is there a too high number for short durations like climb out?
 
See: https://legacy.rotaxowner.com/si_tb_info/serviceletter/sl-912-016-r1.pdf

That is ROTAX's Service Letter SL-912-016R1.

Section 3.1.3 pertains to MP and appropriate operating limits.

I've used the Vans prop pitch tool on every ground adjustable prop I set - no matter what the manufacturer or blade configuration along with a small digital level. Since I don't keep the battery in the level it gets calibrated each time I use it. I consistently see 0.1 degree or less between blades.

See thread meltdown for the gory details of not paying attention to the parameters set forth by Rotax. You can't comment on the thread since the Vans employees closed it - too much heat I guess.

The Vans posters on this forum would have you believe that something other than the parameters outlined in SL912-016 were in play here but that's simply not the case. It failed exactly as Rotax said it would given the parameters in that service letter.

In my situation every parameter in that SL was in play for an inflight engine failure.

I run about 1 degree less bite from the "recommended" pitch in the prop now and it sees just over 5200 on roll out so I feel good about that. Still see numbers in the yellow for airspeed and the bird is so light that any turbulence really pushes it around so I'm good.

It is the owner / operators responsibility to ensure that the engine operates within the parameters of the engine manufactures specification. Ignoring Rotax' "recommendations" could be costly.

And don't get me started on what it takes to work with Rotax. It took 9 months to reimburse me the $4200 for the pushrod debacle on the new engine.
 
Scott,
I?m fairly confident I have her set at 71.4 w/i .1.

Say, is it possible at 71.4 to get a high MP alert on climb out and it goes away at initial cruise?

Thanks,
Doug

Yes - you can configure the Dynon to set a redline for MP. The MP will unwind as you gain altitude but I wasn't comfortable not being able to use full power on takeoff. I just re-pitched the prop.
 
Yes - you can configure the Dynon to set a redline for MP. The MP will unwind as you gain altitude but I wasn't comfortable not being able to use full power on takeoff. I just re-pitched the prop.

Hey Waterboy How much did you flatten it out roughly - .2 or ? to obtain desired results?
 
You can't comment on the thread since the Vans employees closed it

That can only be done by a forum administrator. Van's employees do not have admin. rights so have have no way to close a thread.

The Vans posters on this forum would have you believe that something other than the parameters outlined in SL912-016 were in play here but that's simply not the case. It failed exactly as Rotax said it would given the parameters in that service letter.

As has been mentioned numerous times here in this forum, the cause of the failure has never been full investigated because a partially disassembled engine (with critical p[arts missing) was shipped for evaluation (who does that with a new engine that is still within it's warranty period......???), but that the USA Rotax representatives and Rotax engineers (during a meeting at the 2018 aero-expo in Germany) are confident that there was more involved to cause the failure than just the engine RPM during take-off.
 
That can only be done by a forum administrator. Van's employees do not have admin. rights so have have no way to close a thread.

Vic is both an employee of Vans and an admin on this site. I'm sure you are aware of that.

As has been mentioned numerous times here in this forum, the cause of the failure has never been full investigated because a partially disassembled engine (with critical p[arts missing) was shipped for evaluation (who does that with a new engine that is still within it's warranty period......???), but that the USA Rotax representatives and Rotax engineers (during a meeting at the 2018 aero-expo in Germany) are confident that there was more involved to cause the failure than just the engine RPM during take-off.

Just to be clear: No one from Vans or Rotax has ever contacted me in any official capacity WRT the inflight engine failure. Only the FAA reached out after the incident.

The engines intakes were removed exactly as described in the KAI - during the timeframe of the build - to recover the drip trays and cooling plenum for use on the new engine.

Who does that? Literally all 600 912ULS builders. Since I'm both an A&P and certified Rotax iRMT I actually am qualified to dissemble and inspect these engines. I've had this very conversation with Rotax.

There's no question that the "recommended" pitch is in direct contradiction of Rotax' recommendations and the failures they have seen in the field per the service letter. That service letter IS Rotax' official stance on engine operating parameters. All other conversation, opinions and experiences cannot superceed the official documentation from Rotax.
 
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I need to check the limits my SV SW version has programmed MAP at. However, IF I interpret the chart correctly, then 29" at 5200RPM is the limit I can operate to?? OR is this chart more useful for inflight adjustable systems....? Like a certified C/S prop??

No answer, or no idea...Doesnt matter, I pitched to average 5650 WOT at 3000 MSL and numbers seem real good/optimized. I feel WOT over that and the performance numbers don?t improve but may decline. Just my humble opinion.
 
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