Do you repair your own sewing machines?

I was wondering if there were any folks here handy enough to repair their own machines?

Have you ever thrown your machine's Timing off? I did this once to my serger and had to take it into the shop to get it fixed.

I had a problem not long ago with my Bernina, there is a gear inside that keeps freezing up, and will stop the machine in it's tracks when it freezes up. I took it to the shop the first time and asked him specificially to tell me what was wrong and how he fixed it. Dang it if he didn't just say it just needed cleaning, I knew better, and it did happen again. I called my husband in there and told him the problem, he has a knack for being patient and finding the root of all problems it seems.

He took this machine apart and watched it in action, and quickly found out wht the problem was, and told me what it was and how to fix it from happening again, I now know what was going on with it but don't know why it has happened, and apparently neither did the repair man, as he just fixed it the same way my DH did and wouldn't tell me how he fixed it.

I've never been unfortunate to the point of throwing the timing out on my machines, except that serger the one time. I put it in a huge bind and knew I was wrong when I did it.

I have no patience for sitting down and fiddling with the machines to find the error. I have an embroidery machine just sitting here because I can't get it to go forward, it sews up and down and the presser feet won't move it forward, I know this is simple opperator error but I have sat down for hours with this machine and still not found the error. I just want to pull my hair out with it, so it's just sat there for months now because our closest repair shop for computerized machine is over an hour away.

How handy are you with fixing your own machines?