Push-Up, closely following Keith Laumer - RC Groups
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Nov 04, 2017, 11:37 PM
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david.ingham's Avatar
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Push-Up, closely following Keith Laumer

I am building Push-Up, retaining the size and 020 Pee Wee engine, but adding radio control. This will replace my old Push-Up that flew away to Never Never Land. I have some experience with RC now, so this one may stay around longer.
I want to improve a bit on my old build. I plan three channels, with partial power control by adjusting the mixture.

I printed plans posted on the thread: https://www.rcgroups.com/forums/show...PLAN-Build-Off. I am cutting up my old plans to trace around for part shapes.
Shown are my new fuselage sides, and the old one before and after the crash and re-build.
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Nov 05, 2017, 02:54 PM
B for Bruce
BMatthews's Avatar
I was going to suggest an exhaust ring. But I think you're right and a lever that controls the needle valve over about a 1/3 of a turn should work just fine to take the edge off the power.

Best of luck with the replacement!
Nov 05, 2017, 11:19 PM
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I added a contemporary carbon fiber touch, where the first one broke when it ran into a street.
The book calls for 1" Veco wheels, but 1 1/4 were on Ebay. Heavy, but most of that is in the plan.
I curved the landing gear legs to distribute the landing bending stress more equally along the wire. My Sky Ray landing gear bounces it 10 feet in the air.
Nov 08, 2017, 11:45 AM
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Nov 15, 2017, 10:37 PM
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I am adding three inches too the wing, as I did before. Covered the cowling with Al foil, in imitation of Ryan trainers with Alclad.
Nov 19, 2017, 02:11 PM
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I am making a lot of small mistakes and impressions, and fixing them up a bit.
Nov 19, 2017, 02:17 PM
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I am making some small errors and impressions and fixing them up somewhat.
The wing is 33 " as before, but the top of the tip sticks straight out, so that neither side has a compound curve. I came out that I had to end the planking before the spar instead of over it to make it fit right. Otherwise, it is strictly according to the plan in the book.
Last edited by david.ingham; Nov 19, 2017 at 03:00 PM.
Nov 19, 2017, 02:27 PM
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Looks like it's coming along nicely. Small mistakes are par for the course!

Nov 22, 2017, 12:05 AM
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The silk still becomes lose when the dope (SIG Supercoat clear) dries.
I am using the same 5mm silk for the fuselage as I used for the Dandy wing. For the wing I used 8mm colored silk. It seems a bit dark and a bit heavy.
I am weighting for the electrical stuff to come from BangGood, before I can cover the top and bottom of the fuselage.
Notice my newly acquired Space Bug in the second picture.
Last edited by david.ingham; Nov 22, 2017 at 12:11 AM.
Nov 22, 2017, 06:40 PM
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I had to shim the cabin roof too, because it wasn't flat.
Nov 23, 2017, 11:47 AM
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Weights, so far (grams):
wing 65 finished unless I put on another coat of SIG Supercoat clear. The 8mm silk is heavy.
tail 18 needs control horns and more color dope
fuselage 50 with landing gear, no electricals, color or window yet
engine 30 no muffler yet
battery 22
Nov 26, 2017, 03:47 PM
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The electrical stuff from BangGood came yesterday. The battery is too heavy and has the wrong type connector, no parallel charging port. I bound the Rx and Tx, and it works with a bigger battery.
Nov 26, 2017, 11:53 PM
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It is tending to be tail heavy. Maybe it is the silk covering on the tail surfaces. I don't want to crowd the front bay, because it may be tricky getting the engine control to work well. My old one had no in flight power control. The screws securing the arms of these servos are hard to tighten. I am starting to put oil on the screws.
Last edited by david.ingham; Nov 26, 2017 at 11:59 PM.
Dec 01, 2017, 11:58 PM
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Still putting in controls. I can't remember how I mounted the controls on my 1'st Pushup.
Dec 06, 2017, 06:50 PM
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The engine control gave me some trouble, as expected. The servo popped open when I pushed the arm down and doesn't work after re-assembly. I tried an old one I had and on the second try it worked. The way I captivated the push rod was too tight and the (nine year old) servo chattered and wouldn't turn all the way.

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