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Bob,
To look right and to be scale, both the top and bottom wings have 2° on each side. This is also on Paul Matt's drawing (Historical Aviation Album) of NC 14031, the Pica subject plane.
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John F Howard (aka skylarkmk1) AMA 10955, WACO Brotherhood #26, AWC, NWC
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I am going to start this project and have Pepino plans so this thread has given me insperation much needed information. Great job guys.. As I have never built a bi-plane before, Is building washout into the wings of a bi-plane a common practice or not?
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Thanks John I was perty sure it did but I wasn't sure that it needs 2 degrees in the top wing I was afraid it look funny. But if that be the case then I feel ok to put the 2 degree in THANKS.
Bob Waco Brotherhood # 35
< Message edited by obo -- 10/27/2007 9:46:00 PM >
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Bob, Ken nor I are building washout in the wings. I don't think the washout is necessary on a model like this. I think the purpose of it is to prevent tip stalling on landing, which I am sure none of will do anyway .In looking at the plans, the washout is formed using the inner-plane struts. I am not sure how this is accomplished. It seems to me that trying to do this would pull the trailing edge of the bottom and top wins together, which would in effect cancel out the washout, and probably cause a whole new set of problems worse than tip stalling. Ken, correct me if I am wrong please. "Skylark" or some of the guys might be able to tell us if the Pica kit or the ARF has any washout in them. I have never had a biplane that did. Hope this helps, and good luck. Keep us posted!!! Scott
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BOBFI,
The PICA wings are built flat. The last 3 ribs in the tip (W-6, W-7 and W-8 on the Pica plans) are where any "washout" occurs. The last W-6 needs to be shortenened in hieght slightly along the bottom (tapered) at the trailing edge to be correct. The tops of W-7 and W-8 are nearly level with the rest of the ribs (along the spar/high point), while the bottom angles up and the result raises the trailing edge in that area. The aileron curves up in the same area and the curve up actualy starts between the last 2 W-6 ribs. The YKS and YMF wings are similar in construction (they use the same aileron) and I have had access to the YKS while it is being restored.
P1 Covered full size YKS top wing P2 Uncovered full size YKS top wing, you can see how the last 2 ribs are "tilted", raising the trailing edge.
< Message edited by skylarkmk1 -- 10/27/2007 10:52:58 PM >
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John F Howard (aka skylarkmk1) AMA 10955, WACO Brotherhood #26, AWC, NWC
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I have never intentionally put washout in a biplane wing. I really don't think it needs it. I did put washout in the two Ziroli corsairs that I built per Nick Ziroli's instructions. Warbirds are a different story.
Here is the way the tip came out on my Pepino Waco. Unfortunately Pepino doesn't give much information on the way the tip should look. Does it look alright or how would you change it if you could?
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Ken,
It looks ok, don't mess with it. On the next build I would raise the trailing edge and center of the tip a little. The full size when measured along the spar/high point has the rib W-7 (second from tip) about 1/4" lower and the W-8 rib (last rib) about 5/8" lower. This makes on a 1/4 scale, W-7 about 1/16" low and W-8 about 5/32" low. Compare your picture to the uncovered wing in my last post.
P1 Trailing edge of wing at aileron hinge line. Note upsweep on lower edge start well inboard (between last 2 w-6 ribs) and just the last little bit of the top curves down. P2 Leading egdge of aileron with matching curves P3 Aileron bolted in place, note the last few ribs of the top of the aileron (between the end of the hinge and tip) curve down, just barely.
< Message edited by skylarkmk1 -- 10/28/2007 1:56:52 AM >
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John F Howard (aka skylarkmk1) AMA 10955, WACO Brotherhood #26, AWC, NWC
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quote:
ORIGINAL: Big_Bird
I have never intentionally put washout in a biplane wing. I really don't think it needs it. I did put washout in the two Ziroli corsairs that I built per Nick Ziroli's instructions. Warbirds are a different story.
Here is the way the tip came out on my Pepino Waco. Unfortunately Pepino doesn't give much information on the way the tip should look. Does it look alright or how would you change it if you could?
I appreciate your dialog on the Pepino. I'm making notes for my build. Yours and others remarks will help greatly.
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quote:
ORIGINAL: mango12
Thanks! Printed it to add to my collection.
Your very welcome. If I come across any more similar material I will post it as well. This stuff is not very plentiful. Once it a while something just comes up from an old periodical. Wm. John
Edit: I should include that that page came from Raymond H. Brandley's "Waco Aircraft Production "1923 - 1942"
< Message edited by JoeAverage -- 10/28/2007 10:18:06 PM >
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Great article. I had trouble printing it though. It kept chopping off on the sides for the margins. I just saved it to my pictures/documents and then printed it from there. I only wish the pictures could be printed larger. I'll have to work on that.
Makes you want to build a big one doesn't it? Like my dad always told me. It's just a giant model, you just want to make sure everything is perfect and built to withstand a cataclysmic event keeping in mind weight.
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All Forums >> RC Airplanes >> Scratch Building, Aircraft Design, 3D/CAD >> RE: Jim Pepino's YMF-5 Waco 
RE: Jim Pepino's YMF-5 Waco - 
.In looking at the 
