Fabricating and Positioning Threaded Rod Brackets

This weekend I managed to locate and drill the hole on the opposite side of the wing stand post that secures the angle bracket to the wing stand. I also started the process of fabricating the brackets that will receive both ends of the adjustable threaded rod that will brace the support angle that holds the wing spar. I need to make 8 brackets, and there is a bit of measuring and fabrication work involved, as usual.

The process I used to lcoate the matching hole on the opposite side of the wing stand was to clamp a straight edge across the wing stand so that could get a precise measurement from a another ruler as to the exact distance of the edges of the drilled hole from the edge of the wing stand, as shown below:

I placed the edge of the second ruler up against the straight edge to get an exact measurement. Then I  measured from the top of the wing stand to the top and bottom edges of the hole. Now I have all 4 measurements needed to draw the matching lines on the opposite side of the stand as shown above. I marked and drew the reference lines as shown after reclamping the straight edge across the short side of the stand as shown above. Then I center punched the stand and drilled the hole. The test to determine if I did this right was simple -  if I could continue to push the drill striaght through to the hole on the opposite side, I did it right. Luckily it worked pretty well, and the holes were aligned as expected.

Next came the brackets for the threaded rod supports. I used 5/16 inch threaded rod, and 1/4 inch hardware for these. I also used remnant from the 1.5 x 1/8 inch aluminum angle that I used to drill the nut plate holes in the wing spar flanges. I cut the angles down to 1.25 inches. After making some calculations to allow for bolt head and washer thickness, I determined that probably not more than a 1 inch piece of angle is needed, but I wanted something a bit wider to help counteract any tendancy for the angle to distort or become compressed when the weight of the wings is applied.

First step was to determine where to locate the hole in the stand. I used the pythagorean theorem to determine this. That formula is a squared plus b squared equals c squared for a right triangle. the "C" value is already determined, and this is the length of the threaded rod, which makes up the hypotenuse of the triangle that is formed by this arrangement.  it is 12 inches long. The other measurement that is known is the B measurement. This is 6 inches from the location of the wing stand attachment hole in the support angle to the hole in the support for the threaded rod bracket. That leaves only the A measurement to solve for. I wanted to find the measurement that would allow me to use the stock 12 inch length of the threaded rod without the need to cut or debur the ends of that. It turned out at 9.25 inches left a C measurement of just over 11 inches. This would leave approximately 1/2 inch on either end of the threaded rod to allow for adjustments to keep the wing true with no twist or distortion. SO the measurements of the triangle formed by this support are 6 x 9.25 x 11 inches.the reality is that there is much more thread to use for adjustments because the attach points for the rod are well forward of the center mounting hole of the bracket. This will become more clear with more pics.

So I did my best to mark and drill 2 more holes in the same wing stand that were 9.25 inches below the first hole. this did not turn as well as the first set of holes as far as alignment of the holes on either side of the stand was concerned. I think the drill slipped a bit, and so the bottom bolt is at a slight angle compared to the top bolt. Regardless, I think it will work fine.

Here is the pic of the first hole, again after carefully measuring the location in reference to the forst bolt hole above:

And the second hole on the other side:

And then came the bracket:

It has to be tapered to accept the threaded rod that connects the angle support to the wing stand. I will have more pics as this all comes together. Still a lot of work to do, and 7 more brackets to fabricate. It may take me the majority of next week to finish everything for both Wing stands, but it will get done.