Stephan's Sonex #1627 Builder's Log

I fabricated the SNX-T12-10 clip from a scrap piece of SNX-Z03-02 channel stock. I was supposed to have a 12" piece of SNX-Z02-03 angle stock in my kit to make that part, but it was missing from my kit. I contacted Sonex to find out if there were any issues making it from 0.032" instead of 0.025" and Kerry Fores indicated it was not an issue.

I worked on fabricating more parts for the vertical stabilizer today. I fabricated SNX-T12-03, 04, 08 and 09. The SNX-T12-09 part had to be fabricated from 0.060" aluminum sheet. The bend on the part is 65° and the bend radius was 3.2mm. I used the extension rod that came with my deburring tool which had a diameter of 6.2mm, close enough to give me the proper bend. I used my bending brake with the rod secured as indicated in the picture below. 

I also wanted to fabricate SNX-T12-10, but it calls for SNX-Z02-03 angle stock, which I don't appear to have. I believe the angle stock is 0.032", so I can probably make it from scrap SNX-Z03-02 channel stock.

I thought that I would start the Sonex build with something simple: bending the forward spar fitting. This part came with the tail kit already cut to size, all that needed to be done is bend it to 35°. This proved not as straight forward as I had hoped. I initially inteded to use my Arbor Press, as Sonex suggested with the wood cut out, but I decided to use the dowel and vice method that other builders had successfully used. 

When you're using the dowel method, the dowel is centered between the bend tangency lines. I managed to split my wood dowels so I ended up using 1" diameter steel pipe instead. It is important to make sure that the steel pipe extends above and below the edges of the part, so that you don't get any imprints on the part. The steel pipe tended to move around while I closed the vice, so I drilled two 1" holes about 2.5" apart in a piece of 2-by-4 and split it in half to hold my steel pipe in place.

The steel pipes also tended to deform, so I decided to use a socket wrench with a 1" OD. This ensured that the part had the proper bend radius. I ended up needing to bend almost 10° further just to end up at 35° when the part is removed from the vice.