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Old Nov 14, 2012, 02:01 AM
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white lake michigan
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LOL your bro must be living in the stone age like me. My jvc is from back in the early 80's I guess JVC got there A$$'es sued off over the camcorder I bought. Don't laugh too hard im still using a flip phone.
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Old Nov 19, 2012, 07:42 AM
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Denver CO
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good news , bad news.

Getting real close, and the closer i got the more i realized my estimated AUW has been blown by 10oz!!!!

The fiber glassing added 6oz to the air frame alone.

Current weight: 47oz 21oz sqft for wing loading and counting

That's with no paint, no landing gear and its gonna need them!

Did a quick power test, 460 watts isnt flying this pig!!!

Now i seen these dectrum units fly 3.5lb planes respectfully, but not these two units.

Balancing is a chore,
the hole is not big enough for either top flight mag ballencer or the great planes thumb ballencer. All i could do was get them close, then use the rotate and spin up method.

Still no love.I surprised i didn't blow them.

going to run them up out of the duct work take measurements.

Still need to figure out the cog of the my pig as well.
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Old Nov 19, 2012, 12:10 PM
EDF rules... :)
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The COG looks good as long as the line dimensioned 10.738in is the centerline of the airframe.

Eric B.
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Old Nov 19, 2012, 09:08 PM
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^^^^^ +1. if you've used the root chord, the CG calc will be slightly off. as Eric recommended, you must use the centerline of the airplane and allow the natural lines of the wing outline to extend to the centerline. then take your measurements. 15-25% should be a good starting point. I'm guessing you'll find that 15% might be a tad nose heavy, but that's good too for the first few flights.
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Old Nov 20, 2012, 04:12 AM
smithy
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Cornwall, UK
Joined Dec 2004
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D, that c of g looks fine, mine came out 5.5'' from leading edge root, but it is bigger. She's looking real good, nice progress mate. Btw, you think yours is heavy, mine feels like a 'brick'.

Phil
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Old Nov 20, 2012, 08:43 AM
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Denver CO
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Thats better!

Discovered a bent motor shaft, and slipping edf blades.

straighten the shaft the best we could, replaced the collect with some that had knurls on them no more slippage.

System still needs fine tuning.

Currently seeing a peak of 1050 watts @72 amps,settles in at 960-900 watts with a 40c 2650 zippy


Landing gear in place as well, my bro hooked me up on some simple wire struts no retracts.

AUW now is up to 50oz!!!
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Old Nov 22, 2012, 11:14 AM
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A little heavier flys more realistically
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Old Nov 23, 2012, 04:43 AM
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Waiting for the weather.

I must have done something right with my duct work.

The a-10 has the exact same system and is producing 760 watts with 2lb 14oz thrust with a 56 mm exhaust
the frogfoot is settling in round 950 watts with 2lb 11oz thrust with 53 mm exhaust
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Old Nov 23, 2012, 05:47 AM
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It looks very nice....has the same mean look as the original...Congrats!
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Old Nov 23, 2012, 07:36 AM
smithy
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Excellent work D, she looks great. I think she'll be a great flyer. I need to pull my finger out and get mine sorted.

Phil
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Old Nov 23, 2012, 11:14 AM
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St.Catharines, Ontario
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that makes sense with the smaller diameter exhaust. she'll pick that back up with dynamic thrust at speed and will be much faster than the A-10 with similar power levels. it should fly really well and looks amazing. very well done.

Rich
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Old Nov 23, 2012, 02:18 PM
EDF rules... :)
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Looks great, good luck on the maiden.

Eric B.
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Old Nov 23, 2012, 07:52 PM
Firecracker!
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San Francisco & Santa Cruz
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Won't be long now -- this build has gone so quick, I'm impressed!
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Old Nov 23, 2012, 09:25 PM
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Thanks all,
Weather man better not be lying to me, says 68 and calm.
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Old Nov 24, 2012, 09:35 AM
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white lake michigan
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Looks Great D, good luck on the Maiden.
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