Sat Sep 13 2008

Drilling left longeron

The first order of buisness today was to match drill the center section to the tailcone.

Then it was time to fit the longerons. The first thing I did was to remove these F-711C bars so that the longerons would fit even before I made the notch in them.

Kerin helped me lift the fuselage so I could slip the longerons into position. However, they didn't slide into the notches in the bulkheads all the way. The notches are slightly too narrow. I really don't know why Van's doesn't just make these 3/16 inch wide instead of trying to get them to exactly fit the longerons. Frankly I think that would be better because the edges of these notches are bound to scratch off the primer (once I actually have primed the longerons).

After some work with a needle file, I got them to fit. I had to repeat this filing process at all the bulkhead notches. Grrrr.

At one point, Snickers came down to check out the progress and decided to lounge a bit in his shop dog bed.

After the filing, Kerin helped again and we successfully slipped the longerons into position.

I took an alternate approach to positioning the longerons compared to what Van's recommends. They say to align the aft end of the longeron with the aftmost flange of the F-712 bulkhead. Instead of that, I chose to align the (downward) bend line of the longeron with the corner of the F-770 side skin.

Here you can see that I left the longerons...uhhh...long...when I was working with them originally. I thought I would transfer the cut line while they're in assembly. Unfortunately they overlapped, so I had to make a rough cut to chop them off before continuing.

In preparation for drilling the longerons I went out and bought some new clamps. I really like the large Pony c-clamps I bought at Home Depot, but they don't carry small Pony c-clamps. Instead they had some crappy clamps, so I went to Lowes and got these Bessey c-clamps.

I remembered to grab this close quarters dimple die off the table. I had ordered it earlier this week when I was considering using AN426AD4 rivets to attach the F-776 bottom skin to the F-623L & R gussets. I have since decided to just use extra AN426AD3 rivets. I'll just store this puppy with all the other dimple dies for now. I'm sure it'll come in useful eventually.

Sooooo...back to the longerons. I started using the Dremel and a cutting disc to chop off the ends of the longerons. This was rather slow, however, so I reverted to using a hack saw.

Choppety-bop and they're no longer overlapping.

Then it was a bunch of clamping, aligning, drilling, and clecoing until I had the left longeron completely drilled. (...okay...not completely drilled...I still have to do the #30 holes at the very forward end of the longeron.

Since I don't have to mess with all the notch filing tomorrow, I should be able to get the right longeron drilled in a lot less time.