Appfan

Okay so I'm a first time builder. I'm taking my time, no rush. However I have encountered my first "true learning opportunity". I built up both wing halves with no dihedral. I'm now starting to think that was a mistake. I've been flying for almost 2 years, but this will be my first low wing plane. I have not joined the halves together. So now is the time to make the change. I want to reset the dihedral back to recommended 2%.

So my question, for you kit builders/bashers out there is; what are some recommendations to reset the correct dihedral? I used thin CA on the stringers and tightbond on the sheeting. Let me know if a few picts would be helpful as well.

thanks much,
-Brian

UPF-7

One idea Brian would be to trace the root rib pattern onto 1/8 sheet balsa and cut out two new ribs. Glue one to each root rib of your wing panels. These will add thickness to your root ribs that will be sanded to the proper angle in the next step. Next, prop up a panel so that the tip is 1/2 the total amount of dihedral you want. Now using a sanding block, carefully sand the root rib until the sanding block is flush to the rib. Repeat for the other wing panel. When the two halves are joined together, you will have your full dihedral angle. The trickiest part of the whole process is keeping your sanding block square to the root rib. I hope this helps. Maybe some others will have an easier method. Mark

Campgems

THis is a good method. I would add though to make sure you use tightbond or the likes. Stay away from CA and epoxy here as you don't want to be fighting the glue when sanding.

Some of the guys go for no Dihedral in the 4*60. That and shortening the wings by one bay at the tips makes for a lively roll. The plane flys great with a stock setup also.

On tip I saw was to add a additional hinge on the aileron one bay in, in case that you decide later to shorten the wings.

last, no matter if you build the wing flat or with dihedral, make doubly sure that the LE and TE are matched side to side.

ChuckW

Some of the balsa suppliers offer tapered stock that would work also.

mgnostic

Building on what ChuckW points out. Some kits have even come with tapered stock for building the dihedral joint. A Midwest ME 109 comes to mind. It used the equivalent of trailing edge stock. Just find a piece of solid trailing edge that will span the wing rib from top to bottom with the thicker side at the bottom of the rib. Glue to one wing half and the once the glue has set glue on the other half taking care to align the leading and trailing edges so that there is no twist in the wing. Just be careful about how thick your stock is or you will end up with a lot of dihedral.

AERORICH73

Hi Fellows: Great info here, but there are two words missing here I believe; Dihedral braces. Is this wing built without them? The word I got from some builders is to build one wing panel with the dihedral brace installed, and then position it on the plans to build the next panel attached to it. The completed wing would have the correct dihedral with no misaligned LE, or T.E problems.

What is the threads thought on this?

Rich S.

aerowoof

last tome I saw brades used in a wing was when I built a falcon 56 back in 70 .afterwards most wings were joined by butt joints and strengthened with 6 oz fiberglass cloth and polyester resin,I recentlu built an arf that used braces that you glued indise a box around the spars there were 2 of them that had to be glued together to get the 1/4" thickness but they were made from liteply.I replaced the with a single poece of 1/4 birch ply,since the wing panels were pre covered and no easy quick way to wrap with fiberglass cloth