Carlson Skunk Works

May 27th, 2011

AMF 14H Maranda SN:1026 Making Sawdust May 27, 2011

Posted by Roger in AMF 14H Maranda SN1026, news

More progress and more pictures!

The sheet steele parts are done. The large tube has been cut and drilled. The jig for the windshield frame has been constructed and parts are starting to be fitted into place in it.

These are the finished sheet steele pieces for the windshield frame that were shown in my last post as a a piece of sheet with a bunch of holes drilled in it. I cut them out mostly with my Dremel tool, but finished up using my trusty old hacksaw. Once the parts were cut out I used a file to deburr the edges.

Two of the pieces have bends but I don’t have a metal break. I put each of them in my vice and carefully applied pressure to make the bend. I started with finger pressue until I had about a 20 degree bend, then I used a 2×2 and a hammer to GENTLY tap the tab to a right angle. It seemed to work ok and when I was done I checked the finished angle with a square and it was very close to perfect.

The Windshield Frame Jig

The windsheild frame jig is built from 1/2″ plywood and some fir backing pieces to screw things to in order to keep everything in place. This is used to hold the various parts in position until they are all tack welded together. Once the tack welding is complete the jig will be disassembled to allow access to all sides of each joint. Once all the parts are cut and fitted I will cut the lower back corners off of the sides to make it flatter for transport.

Wing Attach Holes Being Drilled

The top windshield frame tube connects the front wing spars together. A 5/16″ bolt goes through the front spar brackets and a 7/16″ tube that goes through holes drilled in the top tube. This is how I drilled the holes for these bolts in this tube. Essentially this picture shows the drilling jig that I used.

I cut the tube to length and deburred the ends. Then I screwed the blocks on the jig on one side of the tube. Then I put a 3/4″ boart on the other side of the tube and used that as a straight edge to draw a line the length of the tube with a fine point sharpy. Next I made a cross mark 20mm from each end of the tube which is the location of the cross tubes and center punched the location.

The holes are required to be exactly throught the center of the tube so that both wings can be bolted onto the plane at the same angle. So I started by using the extra tube that I cut off off to test my jig. I drilled a pilot hole first and verified that it was being drilled exactly through the center of the tube and to verify that it was perpendicular to the length of the tube. Once I was satisfied that my jig was holding thing properly, I drilled the pilot holes in the top tube. When the pilot holes were done I put a 7/16″ drill in the drill press, repositioned the jig to allow for the longer drill and drilled the finished holes.

After deburring the holes and verifying that the cross tube could be inserted into place, I slid the top tube into the windshield frame jig. I pushed it through the hole in one side piece, then installed the two sheet steele pieces with the bends. I was very careful to orient the pieces correctly according to the plans. Then I pushed the tube through the other jig end.

Now I only have to cut and fit the four 5/8″ tubes that make up the rest of the windshield frame. Oh, and the two cross tubes for the wing attachments.

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