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phintz
03-08-2014, 08:24 PM
Hello, I installed my 72" warp drive prop today, and I'm going to set the pitch tomorrow. What is approx. the starting pitch degree for intial testing, I'm looking for a in between # for cruise and climb!


Also for warp drive install, the 4 bolts for each blade, do you put the heads of the bolts forward or aft. Instructions didn't say, does it matter?


My engine is a rotax 912.


Thanks
Patrick Series 6 builder

SkyPirate
03-08-2014, 09:51 PM
I have the bolt heads forward..582 I had around 11 degree's ..not sure what it is on my 912 for pitch

HansLab
03-09-2014, 06:36 AM
Mine is 12 degrees @ 75% of the blade. (IVOProp, 912UL)

phintz
03-15-2014, 08:17 PM
I called warp drive the other day and he suggested 14 degrees as a starting point, possible going to 15. I was wrong on the size too, mine is a 70 " radius. He also said that every degree added + will drop your static rpm 100 rev. since this is loading the prop more.

just thought I'd share

Thanks again
Patrick
series 6 builder
:D

Wheels
05-07-2014, 08:50 PM
I flew my model IV today with the 70'' three blade warp drive. the most I could get at WOT was 4800. I have a friend who offered his digital level but I don't have a pitch angle tool. Do I need one?
I guess I'll call Warpdrive for the torque values, but can anyone ballpark the numbers.

Jerrytex
05-09-2014, 01:41 PM
I have the Warp protractor and a digital level. I only use the digital level anymore. You can get it dead on with a digital level.

Blade bolts- 120 inch lbs (10 Ft lbs)
Hub bolts- 175 inch lbs (15 Ft lbs)

Wheels
05-09-2014, 01:46 PM
Thanx, I"ll start tonight and report how it goes, although its raining and the cowling is at the paint booth.
Wheels:D

kitfoxnick
05-11-2014, 05:09 AM
I have mine set to 11.5 deg. That gets me a 105 mph cruise and reasonable short field performance. My strip is 900'. Static is 5200.

Wheels
05-11-2014, 11:35 PM
Mother's day, didn't get anything done on the plane but at the end of the day checked the pitch with a yardstick prop holder and a digital level. None of the angles were the same, so tomorrow I'll get serious. Air the tires to exact pressure, digital level the plane, chock the wheels, take communion, then begin. this is my first time but I'm hoping Warp drive will send me some good info on the process. I won't fly the plane till I'm happy with the numbers and I get a go ahead from my inspector.
thanks for helping.

kitfoxnick
05-12-2014, 09:31 AM
When I adjust them I don't level the plane. I take a reading at the hub and take a reading at the tip. Take the difference between the numbers and that will give you your pitch. Make sure you pull out on the blade so the root is set. Another thing is make sure you have the match marks on the hubs aligned when assembling the hub halves.

Wheels
05-13-2014, 08:18 AM
I called warp drive and talked to them. They were great! They corrected my bad measurment technique and are sending me the instructions, tools and torque values to fully enjoy my ground adjustable Warp Drive product.:p

SkySteve
05-13-2014, 01:37 PM
Wheels,
I have a 68" 3 blade square tip Warp Drive prop. I've always measured my pitch from the tip of each blade but my degrees are always different than I hear about here. Did they tell you to measure somewhere other than the tips?

kitfoxnick
05-13-2014, 06:56 PM
Mine is 11.5 at the tip.

SkySteve
05-13-2014, 07:19 PM
Mine is at 9.5 at the tip. Rotax 912A 80 hp. Cruise 92 mph @ 5000 rpm, 100 mph @ 5400 rpm. Off the ground in 350-400 ft. The elevation is 4500-5000 MSL. Empty weight 670#

Wheels
05-14-2014, 08:31 AM
Wheels,
I have a 68" 3 blade square tip Warp Drive prop. I've always measured my pitch from the tip of each blade but my degrees are always different than I hear about here. Did they tell you to measure somewhere other than the tips?

No, they said the tips. I said I was measuring 6" in with a digital micrometer. That gives me more surface area on the flat side for my level. They thought that was fine. When I remeasured last night with their technique, I found only one blade out, but its really out. 5 degrees. So I'll give it a shot today on the ground run with the tools I have. Probably won't fly ;) until I see the tools from warp drive, but I am thinking I can make the vibration go away. I have calibrated torque wrenches and all the numbers.

Wheels
05-16-2014, 11:03 PM
The prop pitch is probably fine now. the vibe went away except at some midrange points and a little more than I like at WOT so I am investigating plugs, and balance. If I can't get it cleaned up with that I will check the clips in the carbs but the vibration is 80 percent bette now that the blades are so close in pitch.

Jch
05-17-2014, 04:49 PM
On a related topic...I was trying to balance my 3 blade Whirlwind that has a carbon graphite spinner and plate. Are there any caveats for drilling through the spinner plate (type of drill bit, edge distance, dont do it all???) to put balancing weights?

Wheels
05-18-2014, 10:43 PM
Ok, the pitch is set. The blades are within about a tenth of a degree. the balance is good with the low mid and full throttle points being smooth as silk. I am seeing 5200 static and 5800 at cruise. The plane is doing well. I'll send pix this week, or next, you have all helped me put together a plane that came to me in boxes. I can't thank you enough.
Wheels

Wheels
06-03-2014, 11:04 PM
I got the vibration back and when I checked the blades, one of them was out by nearly 4 degrees again. Wow! I reset the pitch, re torqued to specs, rechecked the pitch, rechecked the torque, I'll test it tomorrow and I'll send it off if it slips out of pitch. Any other suggestions.

PapuaPilot
06-04-2014, 07:43 AM
Make sure you are torquing the hardware properly. If you have self locking nuts you may not have accounted for running torque. If this is the case the resultant torque will be less then it is supposed to be.

To get the correct torque add the running torque to the actual torque. Example: An AN4 bolt/nut (1/4"-28) has a torque range of 50-70 in-lb., if the running torque was measured to be 5 in-lb then the final torque would need to be 55-75 in-lb. Personally I would take it up to the high end of 75 for a propeller, especially if the blades have been slipping. If you torqued it to 50 without accounting for running torque the actual torque applied to the bolt/nut would only be 45.

Running torque is the amount of torque it takes to overcome the friction for a bolt turning in a hole or a a self locking nut turning on the bolt/stud. You can find running torque by using a torque wrench and measuring what it takes to make it turn.

Slyfox
06-04-2014, 08:52 AM
my thought, if it's just one blade with the problem, possible bad blade. call warp and ask them.

also check your bolts and make sure you are not bottoming out before it tightens the blade. threads aren't long enough. might need to put on washers.

Danzer1
06-04-2014, 09:03 AM
Wheels,


the balance is good with the low mid and full throttle points being smooth as silk

Was this confirmed with a Dynavibe (or equal) digital balancer - Classic or preferably GX2 type?

Greg

Wheels
06-07-2014, 10:07 PM
Confirmed by my hand on the controls. I will take the plane to the big city this month and they will balance the prop. I don't know what they use.

Paul Z
06-08-2014, 07:33 AM
I flew my model IV today with the 70'' three blade warp drive. the most I could get at WOT was 4800. I have a friend who offered his digital level but I don't have a pitch angle tool. Do I need one?
I guess I'll call Warpdrive for the torque values, but can anyone ballpark the numbers.

Yes you need a pitch angle tool. It is the only way to assure you have the level at the right prop angle.