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Old Dec 10, 2013, 02:23 AM
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Electric/DS build thread

I have recently restarted an old electric glider project with some major modifications to fuse and wing layout.

One major change was to cut the original straight leading of the foam core to make an elliptical leading edge. This however has left a thick leading edge and me the task of re shaping the wing. I know I could go out and get new cores cut but I am not looking for competition standards or perfection and in the past know that many wings were shaped by hand.

My plan is to cut different template to gauge the correct foil across the wing but thought I would ask how others have tackled this problem and the challenges they faced.
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Last edited by AUSELECTRIC; Dec 16, 2013 at 04:45 AM.
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Old Dec 10, 2013, 11:58 AM
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How much of the wing was cut off? If it's only the tips you can just use a sanding block and roughly reshape the LE to the shape of the airfoil.
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Old Dec 10, 2013, 02:19 PM
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The cut affects about a third of the wing
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Old Dec 10, 2013, 03:18 PM
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My guess Ause is that you are venturing into new territory here!
Perhaps a series of external templates cut from sections at several stations printed out from Profili2 might help.
If it were mine, I would reduce the wing to a series of multi (two or more) panel straight sections. But you might be running out of material?
Then, assuming you know the airfoil, you could use an end template to assist with the shaping.
Personally, I would not touch an ellipticall planform wing with anything less than CNC shaping methods. The loss of airfoil faithfullness via hand shaping will more than offset any efficiency gained by the improved planform, perceived or actual.
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Old Dec 10, 2013, 05:29 PM
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Thanks Jim, I have plenty of foam and could recut the wing if required. The elliptical leading edge has purely been chosen for the look and not the real or perceived benefits. I know the original wing was a RG15 I had cut for me about 10years ago.

Will continue with some external templates and see how it turns out. Never know may end up with some WR breaking section, lol
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Old Dec 12, 2013, 01:43 AM
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Hi Mick, I wouldn't try it as you will lose the airfoil. If you have some foam, cut a two or three panel wing with short tip sections. Then you can sand the transitions round and blend them into the rest of the wing but not lose the foil. This is pretty easy and you can use the other panels for something else. You could also use your current panels for this wing but cut them short and just make some new tip panels for it.
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Old Dec 12, 2013, 02:46 AM
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Thanks josh, plenty of foam and thinking that fresh cuts may be the way to go with not many responses to this thread. Have been working on the fuse plug ATM
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Old Dec 12, 2013, 04:16 AM
Arrarrar!
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No worries Mick.
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Old Dec 12, 2013, 05:40 AM
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The fuse is starting to take shape
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Old Dec 12, 2013, 07:10 AM
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I have hand shaped in the past. Hard to tell exactly what you end up with but you can get a reasonably good looking and flying airplane from it. Give it a go, especially if doing a repair.
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Old Dec 13, 2013, 07:03 AM
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You could read the instruction for this
http://www.pcm.at/english/Nano/index.html
The last page of the pdf has an interesting method that could be adapted for a foam wing.

Or try the instruction for mark drela's apogee hlg.
http://www.charlesriverrc.org/articl...oilshaping.pdf

Hope it helps
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Old Dec 13, 2013, 03:52 PM
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Thanks for the tip, drella's method looks easy enough to try. I will try and post a pic of the wing core and fuse plug today.
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Old Dec 15, 2013, 02:59 AM
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Here are the pics
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Old Dec 16, 2013, 05:08 AM
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About time I start thinking of a name, was thinking about blister what are your comments, thoughts or knowledge of other commercial planes with this name.
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Old Jan 23, 2014, 05:05 AM
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Well after careful consideration of the shape I decided I did not like the boom position and proceeded to cut my plug to reposition the boom.

I think although additional shaping is still required it now has much better lines
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Last edited by AUSELECTRIC; Jan 23, 2014 at 06:11 AM.
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