- I bought 2 brand new cobalt drill bits (3/32"). The first bit did not successfully make even one hole in the stainless steel of the lower firewall. I used cutting fluid, went super slow, and used a lot of pressure. NOTHING. Finally the bit shattered and went flying.
- Second drill bit, same basic technique, but no cutting fluid. I actually got 3 holes drilled! But after that I could not get any more holes done! The bit would put a little pin prick in the stainless, but that's it.
- So I need to come up with a plan B. I have no idea what that may be, but I've gone through 4 bits and gotten 3 holes.
- What's weird is that I drilled about 40 holes in the stainless last week while it was flat on the table! Why won't it work now, with fresh bits?
I have to give up for now.
===============
So I went on to make two more pieces of the upper firewall assembly (photo #1), and then test fit the rear spar carry through (photos #2 and #3). I'll drill these after I get the fuselage leveled back on the saw horses.
Two more stainless steel pieces of the upper firewall
