Friday, October 26, 2007

Losing my Bearings

I forgot the cardinal rule of auto racing: When everything looks like it's falling into place, you've missed something. Put another way, if anything can be described as "too easy", it is.

I purchased replacement bearings (four, in case we damaged any on installation). I took the upright off the car (it came off without any trouble). I packed everything in a box and arranged to take it all to LMI Thursday evening.

The first thing Bruce did was to take the stub axle out of the upright. As soon as he did, he could see that I had purchased the wrong bearings. Nothing about them was correct -- wrong size (by about 1mm on the OD), wrong type (double-row ball instead of single-row ball), and much too wide to fit the upright. He got the old bearings out without much trouble (he makes it look so easy), but there was nothing else we could do. The parts stores were closed, and none of the other cars in the LMI shop use the bearing I needed. I put all the loose parts back in the box and drove home.

The real shame is not that I wasted all that time driving to Darien. I felt worse that I asked Bruce to stay in the shop three hours after they closed so he could help me. But this morning I have an upright with no bearings, and no access to the proper way to install the new bearings once I get them.

The proper way to install bearings in a cast aluminum part is to start by warming the aluminum part to about 300-350 degrees. This makes the bearing bore slightly larger, making it easier to slip the bearing in. Ideally the bearings should also be chilled to shrink them slightly for even more clearance. Finally, a press should be at hand to squeeze the bearings into place. I have two out of those three here at work and at home. We have a press and a freezer at work, but no oven. We have an oven and a freezer at home, but no press. If the bearings arrive in time today, we may try to warm the upright on a gas grill. If not, I'll have to go shopping for a press on my way home tonight. And then I'll have to do a lot of explaining and apologizing for putting my car parts in the oven.

I'm giving myself until midnight tonight. If the car isn't on its wheels by then (or at least making significant progress), I don't think I'll make the race this weekend.

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