Started January 13, 2003
I want to make the steel parts now because I would like to start assembling the wings. In order to properly align the spars, the aileron and flap support frames will be needed.
I purchased a cheap, but fairly good, metal bandsaw from Harbor Freight Tools. The bandsaw was on sale for $169 (regularly $199) which included shipping. It will cut horizontally or vertically, has 3 speeds and auto-shut off when the cutting is done in the horizontal mode. Here is my new bandsaw in operation cutting a piece of 2" X 2" x 1/8" angle iron:
I set this up to cut and walked away knowing the machine will finish the cut and shut off automatically. Like Ron Popeil says of his famous Rotisserie Ovens "You set it and forget it."
The angle irons being cut will be used to build the jig needed to construct the Aileron and Flap Support frames.
The jig for building the Ail. & Flap Support Frames was outlined in the Summer 1995 Beartracks newsletter. The drawing called for 1" x 1" angle iron but I have made mine from 2" X 2". Here is a picture of my finished jig:
The welds are a little rough as I only had a #2 tip and it was a little weak for the 1/8" thick material. Actually an arc welder would have been best for this material but I don't have one, so I used gas welding. Anyway, the welds will serve the purpose for this application since its only a jig used to hold the parts in the proper location while they are welded together.
The uprights on the jig must be spaced correctly as per the plans at 31.59". Time spent now getting this jig perfectly square and spaced correctly will pay off later with properly fitting parts when you build the wings.
Aileron/Flap Support Frame Ends
The ends of the Aileron and Flap support frames are made from 4130 steel plate. They are the same size for the Ailerons and Flaps. The front ones that attach to the main spar are made from .062 thick plate and the ones for the rear spar are made from .080 thick plate.
The ends are formed into "U" shaped channels. Some builders do this with forms and a hydraulic press (which I don't have). Bill Johnson did in a way that seems simple yet very effective, so I decided to mimic his technique for making the support ends.
The steel plate was cut to the proper shape and a piece of 3/4" thick steel bar was obtained:
The bar was cut 2" wide and the corners were rounded smooth. You can see in the picture above that the end blank has been cut to the pre-bent shape and the bend lines have been marked (the two parallel lengthwise lines).
The bar was lined up with the upper bend line and a heavy hammer was used to bend the steel plate over the bar stock (kind of like the rib flanges were formed).
The whole thing was then flipped over and the other leg was formed in the same manner.
Here is a picture of the Aileron/Flap Support Frame Ends:
Click here to go to Welding Jig & Frame Ends page 2