<December 2, 2007>
Crotch Strap Brackets - Day 4
Finally, back in the shop! I have good excuses for my lack of progress; I was out of town for my brother’s wedding, and then I got a cold, a very bad cold. I’m finally feeling better, but not perfect, so I kept it short today. I finished up the drilling of the crotch strap brackets today. I still have to enlarge the holes in the seat pans for the buckles, but I take care of that later.
It's been a bit chilly here lately. Well, at least by California standards it has been. I fired up the propane heater today, and while I know I am not supposed to used it in an enclosed space, it sure does take the chill out of the room quickly.
To drill the holes to attach the hooker harnesses, I simply follow Mike's lead again. No need to reinvent the wheel. I simply drilled pilot hole ˝" lower than the stock holes. Since the control sticks and belt attach point isn't centered between the ribs, I made sure to mark each part so that I drilled the new holes on the outboard side of the brackets.
I then put the aft bracket back in place and clamped the spacer between them. I then drilled the forward bracket using the hole I just drilled in the aft bracket as a guide.
I then enlarged that hole using my 3/16" piloted reamer. Afterwards I took the reamer out of the drill and inserted it through the holes to see how aligned the holes were. Looks good to me.
Since I didn't have a 5/16" drill bit, and my 5/16" reamer isn't piloted (pointy tip), I took both brackets out and enlarged the holes with my step-drill (Unibit).
I reassembled it, along with the Hooker Harness Crotch strap I borrow from a friend (I haven't ordered mine yet), to check the fit. In a word… perfect!
The AN5-5 bolts Van's provides with the crotch strap kit end up being a bit short for the increased spacing required by the hooker harnesses. The mark on the bolt shows where it comes out the other side and according to my calculations I will need to order some AN5-7s. The -7s have 7/16" of grip, which means the threads won't rest on any of the layers of material.
I repeated the entire process for the left side. Again, perfect!