I started a thread about rear window channel rot a couple weeks ago. Shrinker/Stretchers came up in it. I had the opportunity to experiment with one at my autobody class. It was the more expensive Eastwood.

The first photo, I tried to do the window channel corner. The metal on the top flange started to get pretty thin and tore when I was stretching the outer edge. I cut a slot out of the bottom flange and it started to bend a lot easier. I didn't have time to finish, but it can be done. The top flange would end up pretty thin, probably too thin to butt-weld but could be lap-welded in.

The second photo is a piece for just behind the front marker light. I had more success with this.

I asked the instructor about the cheaper Eastwood models. He said that the teeth in the jaws jaws aren't as hard and need to be kept very clean for them to bite. They should be fine for home/hobby use.

What's the max guage it can handle?

What's the max guage it can handle?
The website says 18 ga mild steel

What guage did you use in the pics?

I think it was 20. I'll measure it when I get home tonight.

I bought a cheap pair as you have described and they more or less useless. I ended up cutting slits to get the shape I was after and then welded them up.

I bought a cheap pair as you have described and they more or less useless. I ended up cutting slits to get the shape I was after and then welded them up.
Good to know. I was considering buying a set. What was the problemm with them?

Good to know. I was considering buying a set. What was the problemm with them?

Well they just didn't seem to shrink or stretch the metal enough to be of value. If you are shooting for VERY gradual curves they will work but other than that they are no good.

The double flange piece took a while to do. I switched from shrinking to stretching for about 15 minutes. I figure this was the best test I could do for the machine. It shrinks and stretches about a 1/16 of an inch at a time.

There's nothing wrong with the shrinker. You just reached the limit of how far you can go with a flange that wide. Use a narrower flange and you'll be able to shrink or stretch it farther before it fails. I like to keep the flanges under 3/4".

Tom

Thanks, I'll try that next time. I wish I would have had more time to play with it but I spent the better part of the day fabbing up an inner brace for my fender.