Gallery#5
Subj: Fuselage wing mount box building jig
Steve,
Below is an email I sent to John Bolding. It shows my box structure I made to put in the top wing mount tube. I was really happy with the way it worked. If you think it is worthwhile to put on the website, I could redraw the drawing using a straight edge to make it look a little better.
Regarding the aileron pulleys on station 3, is the front pulley on the left side the only one that needs to be lowered with an angle iron?
Dan
ED Note: Dan, that's the only angle and the right location... I used an alum extrusion and staked it so it stopped rotating when the cables moved... The holes are 3/16" for all the pulleys and the drawing suggested 1/4"... I had to make little bushings - ugh...
Subj: 3rd x @ charm...I hope
Date: 03/27/2003 3:56:32 PM Pacific Standard Time
From: 5buschs@pionet.net
To: SKiblinger@cs.com
Steve,
Here is the complete previous email, version 2, with the wing mount box redrawn with some straighter lines, and my proposed addition to the rear of the box.
Page 1 of the .pdf drawing shows how to make it from a 48" x 48" x 3/4" piece of plywood. The 3/4" x 1 1/2" strips are oak hardwood that you can buy in 4 ft. strips at Menards or elsewhere. All dimensions are approximate, except for the 43 1/2" which has to be an exact finished dimension. I just made my other dimensions so they would work, leave enough room for the box structure to slide around a little, and make for the least number of cuts to the sheet of plywood. Also, my box is for the 21 1/2" wide fuselage.
Looking from the side, I put my hardwood strips to the outside of the box. (i.e.. in front of the front piece, and back of the back piece of plywood) The side plywood pieces rest on top of the hardwood strips, clearing the cross brace in the bottom of the fuselage. Once the box structure is screwed together with sheetrock screws, position it where you think it should set. You can mark centers on the hardwood and plywood pieces ahead of time to help position it on your chalk line. Also, mark the top where you are going to fasten the wing mount tube.
I fastened my wing mount tube to the plywood with 1/2" copper pipe clamps and short sheetrock screws. Then I was able to slide the box enough to make the wing mount tube plumb. Once the wing mount tube was plumb, I was able to screw 3" sheetrock screws through the (predrilled holes in the) hardwood strips into my table. Once all 4 corners were screwed down, it didn't move anywhere. Measure your predrilled holes out far enough so you have enough room to get in there with your battery powered drill. I only had to do mine 3 times and almost ran out of hardwood strip.
Having the 24" high sides, gave me enough height to screw the arms on the side, going forward to hold the horizontal cockpit tube with the 1/2" copper pipe clamps. Length of the sheetrock screws on the sides varied, depending on how many items I was screwing through.
It was sort of dumb luck that I hadn't already tacked in the side seat braces, otherwise I felt the above procedure may not have worked. Once I had the top cabane structure tacked in, I could unscrew the pipe clamps, and side plywood pieces, and remove the box structure from the table. Then I tacked in the side braces. Checking later, I found out I could get the box structure (unassembled) in and out of the cockpit area with the side braces tacked in.
I was really happy with how this box structure worked, but after doing some more thinking, realized that I could have gotten more use from this box structure for the side seat tubes, seat back, and the V horizontal tubes going back to the top longeron. Page 2 of the .pdf drawing shows my proposed additions. Item 2 could be a flat board on top of the arms. It could be positioned so that it could hold both the seat back and the V horizontal tubes at the proper height, simultaneously. The tubes could be clamped to the board with 1/2" copper pipe clamps if desired.
Item 1 could be a 2 x 2, that is cut to the exact length of the ID between the lower longerons of stations 2 and 3. In the case of a 21 1/2" wide fuselage, that dimension would be 20 7/8". It will also have to be precisely centered and plumbed above your chalk line. The side seat tubes would then be clamped to the ends of the 2 x 2 with 1/2" copper pipe clamps.
Dimensions listed and shown are for using 5/8" tubing for your fuselage.
Hopefully, this will help current builders and inspire future builders for making the LEU fuselage, and the Double E fuselage that is coming.
Take care and thanks for hosting this site,
Dan
Dan Ellerbusch
LEU
Click next line for jig box drawing...
I used small squares of metal 1/16" thick to help tack weld my fuselage. They help shield the plywood from the heat. When tacking the 1/2" crossbraces to the 5/8" longerons, they help center the 1/2" to the 5/8". In the picture shown, only one square is completely under the (1/2") tube.
The area torched behind the copper clamp was formerly the area behind station 3, where you bend the lower longerons. I too, am building on a 12' table, but if Leonard had said you need a 14' table, I wouldn't be building yet. I am in an approx. 9 1/2' x 13' area. And it is tight. After I got the rear part of the fuselage built, I moved it rearward on the table. Replumbed it, etc., etc., then put the box structure in to do the top wing mount tube. The copper pipe clamps are really handy for holding the tubing to the plywood.
After thoughts!
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