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Obby's Spitfire

obollox
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15 Feb 2014 14:32 #46 by obollox

Replied by obollox on topic Re:Obby's Spitfire

Shake a tail feather!

Thanks: Klipkopwildlife, Sarah-Jane Smith, old fart

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Phil Wood
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15 Feb 2014 14:48 #47 by Phil Wood

Replied by Phil Wood on topic Re:Obby's Spitfire

What's with the strip of the different shade of wood?
I've seen some slight variations in shades of balsa, but that looks a completely different wood.
Would it be any advantage to drill lightening holes in it & cover it ?

Pol.

I just own the forum .... you guys make it great thanks.

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obollox
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15 Feb 2014 15:19 #48 by obollox

Replied by obollox on topic Re:Obby's Spitfire

That's what came cut in the CNC wood pack. It is harder than the front section. I think it needs it or the fin would be too flexible I think the built up tail on the hurricane looks better.

Thanks: The Beard, Sarah-Jane Smith

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Eric
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15 Feb 2014 15:51 #49 by Eric

Replied by Eric on topic Re:Obby's Spitfire

It's hard to tell from that photo, but you might need to make the V in the elevator larger, to allow more deflection. You will need plenty of rudder for take-off and landing.

if you are calm and collected when all about you are going berserk - you've missed something important!

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obollox
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16 Feb 2014 14:06 #50 by obollox

Replied by obollox on topic Re:Obby's Spitfire

Think I have enough deflection for some 3D !!!
Got the cowl off and it's mounting is in progress. RH wing should come off the board
in the morning and the under
spar fitted and the edges
trimmed ready for sheeting.
I am fed up with shoveling snow!!!

Thanks: Klipkopwildlife, blue123, Sarah-Jane Smith, old fart

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Phil Wood
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16 Feb 2014 17:02 #51 by Phil Wood

Replied by Phil Wood on topic Re:Obby's Spitfire

That battery looks like it's got room to slip slightly from side to side.
Don't want to ask the obvious or teach granny to suck eggs, but are you sure there's no way it can come into contact with any of those wing nuts/bolts after the cowl is fitted.
I remember Garry telling us that he had a model burst into flame mid flight because the battery slid forward sightly & the motor shaft drilled right into it.
The pictures don't show everything, I can see a wing nut under the battery, but I can't see what's on the other end or the underside.

Pol.

I just own the forum .... you guys make it great thanks.

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Eric
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16 Feb 2014 18:39 #52 by Eric

Replied by Eric on topic Re:Obby's Spitfire

That wing nut is part of the stand, Pol, not the model! There's an identical one in the foreground.

if you are calm and collected when all about you are going berserk - you've missed something important!

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Si_B
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17 Feb 2014 01:20 #53 by Si_B

Replied by Si_B on topic Obby's Spitfire

I think he meant the pack could make contact with the end of one of the bolts that would go through those L shaped brackets on the bulkhead?

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obollox
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17 Feb 2014 02:59 #54 by obollox

Replied by obollox on topic Re:Obby's Spitfire

So you think I shouldn't drive a self-tapper into the lipo!
Don't worry the only thing to touch the battery will be velcro

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obollox
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18 Feb 2014 15:26 #55 by obollox

Replied by obollox on topic Re:Obby's Spitfire

Cowl fitting sorted out, glued some nylon spacers into the cowl to prevent it crushing. RH wing is sheeted. Still waiting on the retracts from HK. Haven't seen the postman recently, probably too scared to ride his bike in the snow!

Thanks: Phil Wood, Eric, Klipkopwildlife, Quorneng, blue123, Sarah-Jane Smith, old fart

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Quorneng
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18 Feb 2014 17:29 #56 by Quorneng

Replied by Quorneng on topic Obby's Spitfire

obollox
Nice build!
A slight concern that the main spar is cut in two by the wheel well. :ohmy:
The wing skin in the area where the load is transferred to the front and rear spars will be under extra shear forces as will the ribs in that area, however as an all sheeted wing I am sure it will have more than sufficient strength but 'in extremis' I would expect the wing to fail just outboard of the wheel well.

I will be very interesting to see how you set up the necessary angles on the retracts!

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obollox
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19 Feb 2014 08:01 #57 by obollox

Replied by obollox on topic Re:Obby's Spitfire

I think most of the load is taken up by the front spar. It seems to be a well tested design and the hurricane was similar in the wing design. I haven't heard of one failing. The position of the retracts is pretty much decided by the position of the bearers. When my bits turn up I will be able to see the angles better. If you go to the TN site and read the article of his spit build, he explains it further.

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obollox
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24 Feb 2014 13:56 #58 by obollox

Replied by obollox on topic Re:Obby's Spitfire

My bits turned up at last. Got the retracts and the struts sorted out. Had to thin the wheels down in the drill press to get them to fit. Servos and mountings made and fitted, ready to sheet the underside of the wings.