HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Jan 08, 2009, 05:00 AM
56S
Certified Balsa Breaker
56S's Avatar
Joined Nov 2006
1,468 Posts
Question
Tips on installing the top wing on a biplane with only two hands?

I've run up against this one too many times before and thought I'd ask TWOTG to see if there is a better way to get (in this case on a Herr Stearman) six struts and a wing to all play together happily. I've never felt comfortable glueing the struts to the bottom wing/fuselage for fear of a small error in alignment somewhere so what I always end up with is a pile of cards so to speak. Any hints?
56S is offline Find More Posts by 56S
Reply With Quote
Sign up now
to remove ads between posts
Old Jan 08, 2009, 08:41 AM
Neophyte hacker
portablevcb's Avatar
Albuquerque, NM USA
Joined Sep 2003
15,684 Posts
Jigs.

I get the foam core posterboard. Cut four pieces to hold the wings near the root and near the tips. Put another piece(s) in between to hold them in alignment. Can also get fancy and put in some dowels to hold rubber bands across the wing panels. May also need a couple to hold the fuse in the right alignment. When making the jigs cut them so you have the proper dihedral for top and bottom and any washout you might want.

Carefully align everything and make sure struts and cabanes fit properly. Then start gluing. I like 30 min epoxy, or PVA type glue. They bond very well and take a while to set, giving some time to make sure everything is aligned.

If I plan to add rigging I will do it while the jigs are still setup.

After everything is set I remove the jigs. Sometimes I have to cut the foam board apart to get it off the plane.

charlie

PS for Rake designs this is not necessary. For his you simply mount the upper wing using the proper length struts. The bottom is 'suspended' from it, geometry determined by the root 'pins' and the struts.
portablevcb is offline Find More Posts by portablevcb
Reply With Quote
Old Jan 08, 2009, 09:16 AM
Gentle 'Bella'
gnats82's Avatar
Augusta, KS USA
Joined Dec 2007
4,666 Posts
N2856S -

I used a method very similar to that of portablevcb's post but my Stearman was a scratchbuild from foam. I used foamboard to jig the wings at their proper relationship at the interplane struts and glued them together off the plane. I glued the cabanes into place on the fuselage in their proper orientation. After all was set up, I slipped the wing assbly. into place and glued at the wing saddle and cabanes with some sort of aliphatic resin glue and made sure to have just a little pressure on the joints for a snug fit.

I realize you're building a kit with a rigid wood structure and would have to alter the method to suit your construction but the foamboard is really handy to work with and accurate to fabricate. My finished model flew with no vices and trimmed out easily.
gnats82 is offline Find More Posts by gnats82
Reply With Quote
Old Jan 09, 2009, 04:55 AM
56S
Certified Balsa Breaker
56S's Avatar
Joined Nov 2006
1,468 Posts
Thanks guys, I think I can picture that and will start carving some foam blocks. I hope to have it ready to cover in the next day or two and will let you know how the final construction goes.
56S is offline Find More Posts by 56S
Reply With Quote
Old Jan 09, 2009, 06:14 AM
Registered User
peterangus's Avatar
Blackpool, Great Britain (UK)
Joined Dec 2003
1,342 Posts
A couple of photos of wing alignment jigs.
peterangus is offline Find More Posts by peterangus
Reply With Quote
Old Jan 09, 2009, 10:56 AM
Light and floaty does it
Work in Progress's Avatar
Cambridge, Great Britain (UK)
Joined Sep 2004
2,859 Posts
Another good material for this sort of activity is the depron bases from some supermarket pizzas. Eat the pizza and one is sufficiently fortified to assemble the aeroplane.
Work in Progress is offline Find More Posts by Work in Progress
Reply With Quote
Old Jan 09, 2009, 11:46 AM
Registered User
P_J_Glor's Avatar
Valencia, CA
Joined Oct 2002
3,657 Posts
Where the center section is flat, some builders use a small board of balsa or foam to set up the cabane lengths and alignment to the fuselage rather than fighting the whole upper wing. If you do this, make sure you use the same method of strut attachment to the jig board as that for the wing.

Pete G.
P_J_Glor is online now Find More Posts by P_J_Glor
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Help clear the fog on Amps/Watts with these two motors? jbarr2000 Beginner Training Area (Aircraft-Electric) 8 Jul 11, 2008 02:54 PM
Discussion ESC for brushless with only two wires? Spiteful Power Systems 7 Sep 24, 2006 06:24 PM
Question CG on biplanes with forward top wing floss Scale Kit/Scratch Built 18 Jul 28, 2006 05:46 PM
Biplane with only bottom wing? Montega Modeling Science 1 Dec 02, 2004 02:44 AM
anyonw know if i could move my top wing on the gws pt-17 to make the CG more aft? jeff262 Foamies (Kits) 4 Jan 08, 2004 09:54 PM