Wing Building

[Geoff Daunt]

Hope someone can give me some advice.
I have bought the CAP plan and pack for this model.Has anyone built it.!!!
No instructions and probably a bit too difficult for me but l carry on bashing the balsa.
Fuselage fin and tailplane built but l am struggling to work out how to build the wing.
The centre section is ok and built but the two end panels have a dihedral of 6" at each tip. The root ribs are about2" in height and the end rib about 1/2". The ribs are about symetrical.
Clearly l cannot build flat on the board, given the wing taper. I can only think l will need to construct some sort of jig upon which to build the wing at an angle for a 6" dihedral.
Any advice or tips would be greatly appreciated

[Danny Fenton]

Hi Geoff, I am not familiar with this model, but usually you would build the two wing panels flat, propping up the trailing edge towards the tip for wash-out perhaps. Once the panels were made you would then join the outer wing panel spars to the pinned down centre section spars with the tip of the wing panel propped up to achieve the required dihedral. The outer panels root rib would normally be omitted as it is actually the centre section outer rib.
Forgive me if I have missed something strange about the design of this particular wing, and am teaching you to suck eggs, which is not my intention.

[Geoff Daunt]

Thanks for the reply Danny. The problem is you cannot build flat because of the taper of the wing ribs. they are not of equal height tapering from 2" at the root to 1/2" at the tip. Think of an elongated triangle. The taper needs to be equal on both sides and you cannot acheive this if you build one side flat. I hope this explains my problem to you and anyone else who might be able to assist

[Mike Rolls]

Geoff
You will effectively have to jig the ribs into position. Doesn't have to be anything too elaborate -simple bits of balsa sheet, appropriately sized, will do. All they have to achieve is holding the LE, TE and any botton surface spar/s in their correct relationship. Bit of a fiddle but once you get into the swing of it, quite straightforward.
HTH
Mike

[Danny Fenton]

Hi Geoff, ahh now I understand sorry about that. As Mike says you will have to lift each rib with a jig. In the past when I have built tapered wings such as the Hurricane, the ribs have been designed with lugs front and rear to hold them the correct height from the board, once the wing is complete the lugs can be removed and the bottom sheeted. I am surprised the designer didn't help you a bit by doing this. I guess no jig at the root, increasing with each rib to 3/4" at the tip rib will work. Then you can add the dihedral when you join the wing panel to the centre section.
Good luck and let us know how you get on :)

[Geoff Daunt]

Thanks for the replies guys. Guess l better start jigging. !!

[Evan Pimm]

Or you could build it flat on the lower mainspar and simply angle the inner rib at the right angle to mate with the centre section.
Evan.

[Andy Green]

This wont help you here but may be useful in the future especially if you build from plans -

I have a piece of steel tube about 1M long (you can buy similar chrome plated from B&Q) and a smaller off cut that I have sharpened, so as to be used as a cutter.

I cut rib blanks and slide them on the tube with the root & tip rib profiles and make my ribs with the swndwich method.

All I have to do is space out the ribs twist in any washout and assemble the panel. the ribs are held tight on the tube.

Andy

[arthur bishop]

Hey,Hey,Andy..superb,that stirred my brain without the pain! yes,I've got pieces of tube,also threaded rod....I had been wondering about jigs for wings and fuzzes,it takes me back to my early modelling days,excitement again! all those early rubber jobs,Heston phoenix,Defiant,
so many for Dads pocket to pay for...