Saw Straightening Questions

[Greg Crawford]

I have several old "dog" saws to practice sharpening and straightening. I've followed the tutorial on straightening by Bob Smalser (thanks Bob!), but the first one I tried got better but not straight. I'm using a 32 oz. ball peen for the large hammer, and a 12 oz. for the small hammer. After the gentler hits didn't produce results, I whacked it pretty good for the heavy hits.

Are these good sizes? In the tutorial it looks like the large hammer is about a 3 lb. small sledge. The head would be larger, so maybe the impact is spread out more. Does this make a difference, or am I over-thinking this?

I also read that some saws have already been worked so much the metal can't be stretched any more. Is there a way to tell?

Also, I have an anvil that's slightly convex. Should it be flat?

Thanks,

Greg

[Bob Strawn]

I have several old "dog" saws to practice sharpening and straightening. I've followed the tutorial on straightening by Bob Smalser (thanks Bob!), but the first one I tried got better but not straight. I'm using a 32 oz. ball peen for the large hammer, and a 12 oz. for the small hammer. After the gentler hits didn't produce results, I whacked it pretty good for the heavy hits.

Are these good sizes? In the tutorial it looks like the large hammer is about a 3 lb. small sledge. The head would be larger, so maybe the impact is spread out more. Does this make a difference, or am I over-thinking this?

I also read that some saws have already been worked so much the metal can't be stretched any more. Is there a way to tell?

Also, I have an anvil that's slightly convex. Should it be flat?

Thanks,

Greg

I too am looking for answers on this one. I have had pretty spotty results. Some blades have wanted to be fixed and seemed to just go where I wanted them. Most of my results have been embarrassing.:(
Seems to be a knack I have not quite caught on to. I have at times thought I had it figured out, only to find that on another chunk of metal, I have no clue what I am doing. Saws are large area, thin, and should be pretty well perfect, close enough just won't do.

Bob

[george wilson]

Saw anvils were convex.

[Greg Crawford]

Thanks George. At least I'm on the right track with that.

[Kirk McElhinney]

I too have tried Bob's tutorial with limited success. I read Harold Payson's book on saw sharpening in which he talks about straightening a saw by putting the bent area between open vise jaws and tapping with a hammer. I tried it and worked the bends out. One word of caution, go easy with the hammer!

Kirk

[Adam Cherubini]

I've had sucess just pulling out gentle curves by hand. I'm not sure you can planish out kinks. Georhe, you're going to laugh. I asked Kaaare if I could hold a saw he was using during a break at the conference. I'm not sure it was one of yours. May have been some Pax saw. Anyway, it had a pretty good curve in it. He said they'd tried everything to no avail. I grabbed it and pulled it over my thigh and straightened it out. I didn't get it perfect. I think I recall you saying you did something similar except maybe you pured hot water on it first?

Straightening a saw with a hammer can be tricky business. Especially old saws which seem to be pretty brittle. New steel can be moved around and 100 light hits are all that's needed. I use a light weight body hammer (planishing hammer) used by auto body guys. It has a very very thin hickory handle. Bing bing bing bing just like that.

Greg, if you are coming to Woodworking in America, bring your saw with you and let me take a look at it. There'll also be a guy there with some experience with saws named Mike Wenzloff who may be able to help.

Adam