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Joined: 1/20/2004 From: Emerald,
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It's a beautiful 60F right now with light winds out of the NE.. I'll be test flying some quickies after work I think.. Of course, last Wednesday it was 32F and the snow plows were out.
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Joined: 1/20/2004 From: Emerald,
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Ok, I'm going to try and bring this thread back on track.. I just ordered a new LS Q-40 engine and I was wondering about the wood props for these as they seem to like the lighter pitch APC's.. I heard Travis was running the 7.4 x 7.5 when he set the record.. So who's using wood with the LS and was there anything different you did compared to the SS engine??
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Joined: 6/28/2002 From: Arlington Heights,
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Old Style is affectionately know as "MOLD PILE" in Chicago. But Still very popular here. You know it is a good beer when you can buy a 30 pack for $10.99. Haven't been to a CUBS game in awhile, but that was the only beer you could buy at the ball park. Now you know why Wrigley still uses troughs!
Lee, wood prop wise the same holds true. You need to get a prop that turns near the 25K mark at peak. Your props will need to hold up to the increased RPM. Concessions should be made with tip thickness and wood selection. Long, straight, tight grain is always preferred. The numbers Tom published are still good.
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Joined: 4/30/2006 From: Cincinnati,
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Lee, Don't give up yet. The new motor offers new challanges. My woodies worked OK but not as solid as I hoped. My best time was a 1.01 for the whole contest. I , also didn't fly very well.My times could have been a bit better. I think Dan's close with the 25K mark and maybe a little more. Mine were turning over 25,500 and maybe just a little too much. The plastic props seemed to be pretty solid. Also I must say there were very few failiers of both Plastic and wood. 1 or 2 of each if that. The engines were a bit of a challange to get set up correctly but most got it together in the end. Much was learned at this contest. Good luck and keep it going. Tom
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Nope, not giving up, not yet anyway..
If I haven't said so before Tom, thanks for all the info you've provided. It's helped me a lot and I'm sure it's helped some others as well.. I actually enjoy working the props, almost relaxing.. That is of course until you find out for some reason they don't go
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Joined: 12/7/2001 From: Andover,
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7 more props done in the past couple weeks, hope to do a little testing today or tommorrow at the field. Dang I really hate that CA bath, but it really seems to strengthen the props.
Do you think doing the same with Dope (Midwest Aero Gloss Clear), would accomplish the same thing? I know it will take longer to dry, but even though it smells bad, it doesn't give me a 3 day head cold.
One last question, I'm doing most of my testing on a SS motor, if your looking for 25k on the LS, what would that equate to on a good SS motor? 24K?
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Joined: 12/7/2001 From: Andover,
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The Norman prop factory.
Props, blanks, sanding blocks, pitch gauge, prop balancer, dial caliper, prop mitre box, prop storage boxes, sand paper, 6" pipe for bathing props in CA, Mothers polish.
2nd picture is a closer pic of the "prop mitre box" that I made. For getting both blades cut exactly the same length, and overall prop length at 7 3/8", this thing works great. It has a 1/4" 20 nylon bolt that holds the prop in place and a slot for the zona saw to get a consistent angle and length at the the tip of the blade. It even sports the Norman race colors
3rd picture is a modified clothes hanger, for letting CA soaked props dry in the breeze.
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Joined: 4/30/2006 From: Cincinnati,
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Man you are the Prop Factory. That represents a lot of testing. I think that on the SS motor you might look for 23,500 and 25,5 to 25,7 on the LS and trim till you feel it's unloading well in the air. Good luck. Tom
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Joined: 12/7/2001 From: Andover,
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Sanded down another 8x7 tonight, slightly rounding the LE near the tip (outer 1 1/2" from the bottom up, per a conversation with Grunk in Florida. Also tried soaking it in DOPE versus CA. Actually smells worse, but it doesn't affect me as bad.
The Dope doesn't seem to penetrate the wood as much as the CA, we will see if it is an effective alternative. The CA really seems to harden the blade, especially the tips.
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Joined: 12/7/2001 From: Andover,
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I ran a couple of my woodies yesterday, and I may be sanding a bit too much of the blade away.
I'm getting a pretty consistent 24 - 24.5 k rpm out of the ones I have done with a good strong SS. The ones at 24 unload better in the air, but at 24.5 it seems too much, lots of noise, but not a lot of unload. These may make good "bad weather" Muncie props, but wouldn't be much good in Phoenix.
After 3 flights, I noticed a stripped gear on my rudder servo, so it ended my day. The locals at my new field were definately curious about the q40, I don't think any of them expected it to be that fast Thankfully, the safety officer was there, and helped me launch the plane. He didn't seem concerned about the noise or speed of the plane at all, so I may have found a new home to practice
< Message edited by daven -- 5/29/2007 4:05:27 PM >
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All Forums >> RC Airplanes >> Pylon Universe - RC Pylon Racing >> QM-40 Racing >> RE: wood props 
RE: wood props - 
from the bottom up, per a conversation with Grunk in Florida. Also tried soaking it in DOPE versus CA. Actually smells worse, but it doesn't affect me as bad.