Sunday, August 19, 2007

Too spooked to drill

It's 57 and rainy in Minnesota today so I fired up the Buddy Heater in the garage to see how hot I could get it. By late afternoon, it was up to 74, so I put the canopy back on the fuselage and lined it up with an idea that maybe -- maybe -- I would drill it. Working with the plexi these last few months, I've gotten a little more confident that maybe this idea was wrong that if I so much as look at it the wrong way, it'll crack.

I thought I was happy with the aft edge but I'm really not. It lines up fine on the pilot side, but I took a little too much off the passenger side and it's slightly forward of the line I drew in the middle of the rollbar. So I'm thinking a little more about this and what to do. But that's not my problem.

You know those builder sites that show a builder drilling some scrap plexi and noting that, try as they might, they couldn't get it to crack? I had no such "problem." And now I'm way too spooked to drill this thing.

Using an Avery plexiglass bit in the cordless drill, I put a little pressure on this scrap piece -- not a lot but I'll bet it's not much more than I'd put on pushing in the side of the canopy as I drill it.

This first time, I drilled at a normally speed, and just before the bit broke through, snap! The piece flew about 4 inches.



Here you can see that it broke just as it was about to break through.



Next, I didn't put any pressure on it, but drilled at the same speed. As you can see -- hopefully -- cracks developed:



I experimented a little more, not with putting less stress on the plexi, but slowing down the drill speed. I got it down to where it was turning very slowly, and while it took a long time to drill through it, it didn't snap this time, even when I put on a fair amount of pressure.

Obviously, there'll be no canopy drilling today. And if I can get the garage up to 90 degrees sometime this week (supposed to get hot again), I'll run these tests again.

But, boy, am I scared to death now.

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