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Old Mar 11, 2009, 11:38 AM
treefinder
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I think we're two common foamy flyers separated by semantics. Do you always put the tips of the balance jig at the cg location identified by Tony? My way of understanding achieving the cg is to move the tips fore and aft (or the plane fore and aft assuming the jig is clamped to the table) until the plane sits perfectly level. At that point, the tips are at the CG/(fore/aft) balance point as the plane is configured. If i want to move the cg forward, i move something (typically battery) forward and that shifts the cg, so when I put it back on the jig at original location, it will point nose down, so i move the plane aft on the fixture til it's level again and the new point the tips touch is the new cg. Make sense?
Further, if the plane sits level when tips are at the Official cg, and plane flys tail down, then that plane needs a more forward cg location (all other things like thrust line, etc. being equal)

nothing quite as much fun as watching two engineers having a "discussion" eh? 8^)
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Old Mar 11, 2009, 01:07 PM
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I agree with Springer, but make that 3 engineers

chewy
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Old Mar 11, 2009, 02:00 PM
treefinder
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Ha!
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Old Apr 12, 2009, 08:49 AM
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Hey guys,
I have all my pieces cut out, and hope to start assembly this afternoon. I do have one question though. Is there anything under the leading edge of the KFM3 strip to put it at an angle to the wing panel or does it lay flat on the wing panel?

Thanks to Tony for the plans and everyone else for all the great info on this site!
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Old Apr 12, 2009, 09:19 AM
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Quote:
Originally Posted by Captain Bravo
Hey guys,
I have all my pieces cut out, and hope to start assembly this afternoon. I do have one question though. Is there anything under the leading edge of the KFM3 strip to put it at an angle to the wing panel or does it lay flat on the wing panel?

Thanks to Tony for the plans and everyone else for all the great info on this site!
Capt... The leading edges are beveled 45 degrees. When glued and spliced together the form a curved leading edge when you fold the foam over and glue it to the spar and KFm strip.
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Old Apr 12, 2009, 11:50 AM
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Foamenator,
Forgive me for being dense, but I still don't understand. I am pretty sure I understand how to build the wing back to the first step, but the second piece is what I don't get. Should the most rearward piece be flat or angled? Which sketch has the red part correct?

Thanks
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Old Apr 12, 2009, 12:33 PM
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Quote:
Originally Posted by Captain Bravo
Foamenator,
Forgive me for being dense, but I still don't understand. I am pretty sure I understand how to build the wing back to the first step, but the second piece is what I don't get. Should the most rearward piece be flat or angled? Which sketch has the red part correct?

Thanks
No problem Capt.... lst sketch is correct butted against the spar and flat against the bottom piece. Bpb
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Old Apr 12, 2009, 02:22 PM
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Quote:
Originally Posted by Foamenator
No problem Capt.... lst sketch is correct butted against the spar and flat against the bottom piece. Bpb
OK, got it now. Thanks Foamenator.
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Old Apr 12, 2009, 05:08 PM
treefinder
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parallel build! I just finished cutting the templates out (finally!) prob cut foam later today.

Question for Bob, how much rounding of the fuse could you do? Pics of your (beautiful) version look pretty cylindrical, Did you have to add fillets for extra meat to sand the contours? also, which way did you run the "waves" in the blucor?
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Old Apr 12, 2009, 06:59 PM
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Quote:
Originally Posted by springer
parallel build! I just finished cutting the templates out (finally!) prob cut foam later today.

Question for Bob, how much rounding of the fuse could you do? Pics of your (beautiful) version look pretty cylindrical, Did you have to add fillets for extra meat to sand the contours? also, which way did you run the "waves" in the blucor?

Hey Springer.... Glad your are working on the P-40. The only thing I did to get cylindrical nose was add a pieces of 6mm styrofoam to the nose area to give me the material to contour around the spinner and work in the radiator.
I also added a 1/4" piece to the cowling top to allow me to curve the fuse downward to the nose.

The rest is square with rounded edges. I used Cellfoam on the fuse so I didn't have the waves, but I would think you would want the waves running the length of the fuse.


Hope this helps, but let me know if you need more pics. Bob
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Old Apr 12, 2009, 08:07 PM
treefinder
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Great, thanks! If I understand correctly that black piece fits between the front end of tony's plan fuse side and the spinner, covering the motor, and makes the transition from "squareish" to round? I'll plan on adding some foam at those places.

Are those pics from the autopsy of the original nose? 8^)
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Old Apr 12, 2009, 10:02 PM
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Quote:
Originally Posted by springer
Great, thanks! If I understand correctly that black piece fits between the front end of tony's plan fuse side and the spinner, covering the motor, and makes the transition from "squareish" to round? I'll plan on adding some foam at those places.

Are those pics from the autopsy of the original nose? 8^)

This is the new nose job.
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Old Apr 20, 2009, 09:47 AM
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Word of Thanks

Foamenator Just have to give you a word of thanks for the great build thread and Tony for the great plans. You guys make this hobby so much fun

Attached is a couple of pictures of my P-40

Foam I used is foam board from the Dollar Tree

Plane flys great
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Old Apr 20, 2009, 10:36 AM
treefinder
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Outof: Bet one can't tell one from the other up in the air! Looking good, how's she fly?

Bob: Just checking, I assume your esc and battery wound up in the forward top compartment and rx, two tail servos in the aft compt, with ailerons on wing. Also notice you did torque rods? what dia? any picture of the actual link to servo connections for them?
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Old Apr 20, 2009, 12:35 PM
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Hermann, MO
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Quote:
Originally Posted by Captain Bravo
Foamenator,
Forgive me for being dense, but I still don't understand. I am pretty sure I understand how to build the wing back to the first step, but the second piece is what I don't get. Should the most rearward piece be flat or angled? Which sketch has the red part correct?

Thanks

I have a question now. Should someone (Tony) rename the 2nd wing? That is what's called out in the design for the BBAP1, i think it was called a KFm3 "Heavy Lifter". Can one of the brainiacs here explain the differences in characteristics to me please?

Thanks,
Tim
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