Setting up to the correct angle, nothing more than a balsa strip

16 January 2025

Scenario 1

How does one go about setting the wing panels so that both are to the correct dihedral angle?

Here's a possible solution:

• Find the surfaces where the angle can be set. Examples: wing spar, fuselage spacer, and in the case of the tail surfaces, the elevator spar and the fin spar.
• Get a flat strip of 1/16" thick balsa. 
• Score the strip, snap the balsa gradually so that the cranked strip is still in one piece and not broken into 2 pieces. Offer the legs against the 2 reference surfaces, douse the snapped joint with superglue. If building from the plan, offer against the referenced lines.
• Use the cranked strip to set up one wing panel and then use the same bent strip to set up the other wing panel.

This can be made to any angle.

Scenario 2

How about making some right angled pieces so that the wing ribs can be set up perpendicularly to the spar and vertically on the building board? Yes, that ought to be possible:

• Make rectangular balsa pieces to the desired length to support the ribs, something that is a bit higher than the depth of the largest rib would do. For example, if the rib is 1/4" deep, something like 1" length of 1/4" width of 1/16" thickness (any thinner it won't be durable or re-usable, any thicker the cracked piece might break right through).
• Score in the middle of the rectangular balsa pieces, i.e. at the 1/2" mark of the 1" length. Snap the pieces and place against a right angled surface. Wick some superglue on the snap line to lock in the right angle.

Placing these cracked up pieces either flat or on edge on the building surface will provide support at a right angle. Keep them in a box as they can be re-used.

You can also make some pieces in other angles (for example, for use in setting up the root rib to the dihedral angle). Just remember to mark the angle on these customised pieces less you forgot what it is for.