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Peter Scoma
07-11-2011, 12:18 AM
So I found a 1" swan paring chisel in an old box of tools at an antique store for 5$. When I went to flatten the back of the chisel, I realized the chisel is bent, fairly acutely, at about 3 inches up from the edge. The chisel (wo handle is about 7-8 inches total). It appears that someone must have used it as a pry bar since it bend at such a specific point. It is bent at maybe 1-2 degrees. Its a real nice piece but im not sure how to go about fixing the bend. Should I heat the chisel and then bend it back or do I risk affecting the metal?
Any help would be appreciated.
Thanks
PJS

Mike Henderson
07-11-2011, 12:26 AM
I just use a hammer and beat it back straight. The metal is not so hard that it'll crack. If you want to avoid hammer marks on the chisel, put a piece of wood on the chisel where you want to hammer it. Swan chisels are nice but they're not that rare. If it has the full logo - "James Swan Co" above the swan logo, and the words "Best Cast Steel" below the logo - it might be worth a bit more than if it just has the words "The James Swan Co" on the chisel, and no logo. Even then, it's probably only worth maybe $30-$45, depending on condition.

Mike

Peter Scoma
07-11-2011, 2:06 AM
Thanks for the info and education Mike. It has the logo and "best cast steel" stamp but its a user to me so I'm really just interested in making it functional. Tomorrow ill try hammering it out with a lignum vitae scrap and see where I get. Thanks for the reply.

Peter

Pam Niedermayer
07-11-2011, 4:49 AM
Some paring chisels are intentionally bent slightly to give the user the ability to pare mortises while protecting the hand. I don't know whether this was the case when Swans were made, but probably. Therefore, it's time to be careful.

Pam

Terry Beadle
07-11-2011, 10:36 AM
Before hammering I would recommend you warm it up in an oven to about 300 degrees. This will make the metal mallable but not affect the hardening. Also, I'd use a vice to do most of the straightening before I'd start with the bigger hammer technique. It's more controlled with the vice and will allow you to see how well the metal will take rebending. Some times old metal is reluxtant and a bit of a warm up gets the molecules ready.

george wilson
07-11-2011, 10:40 AM
IF the chisel is bent in a continuous curve so that the handle just clears the wood when the chisel is laid BEVEL UP on a piece of wood,so you can pare down the wood without the handle hitting the wood,it may be original.

But,you say it has a sudden,acute bend. That may be abuse damage. Evaluate the chisel carefully,therefore. If it BENT it can probably be straightened. If it was MADE that way,you may break it trying to straighten it..

IF you polished a surface,and heated it CAREFULLY until it is a medium brown,and NO HOTTER,you can bend it like a noodle as long as it STAYS HOT. You need to work quickly. Putting the chisel in a vise will quickly suck the heat out of it,and render it brittle. Heat it up,and hammer out the bend with a wooden mallet ,or something that won't leave permanent dents in the metal.

Heating to a medium brown will not affect the original temper in any way,since it was tempered at that heat to begin with. I suggest you lay the chisel WITHOUT its handle,on an electric burner,with the cutting end hanging well off the burner. let the colors develop slowly. Take it off when the chisel develops a golden yellow color. It will keep getting darker. If it starts to turn PURPLE,quench it in water at once,polish of,and heat again more carefully this time. As long as the purple color is not allowed to get near the cutting end,you will be o.k.. Since the bend is 3" from the end,you should be able to heat until the colors are past the bent place,but not all the way to the cutting edge.

Having said all this, Mike's suggestion to beat it flat will most likely work,since the chisel did bend while cold. It probably can be bent back. In cases where something is very valuable that I mustn't break,I use the heating it up method.

I don't know if Swan chisels were BITTED. Many old large chisels had a thin layer of hard steel welded to the belly side of the cutting end. This is usually about 2" long,when new. When you polish it,or file it with a fine file,this hard steel will look shinier than the rest of the body. If you can determine that the chisel is bitted,you can beat the soft body and it will not break.

Mike Henderson
07-11-2011, 10:46 AM
Pam may be right. All the ones I've seen that have a bend in them to give you more finger room have the bend at the junction of the socket and the shaft of the chisel. I've never seen one that I thought was intentionally made with a bend further down the chisel shaft. You mention that the chisel is a paring chisel rather than a regular bench chisel and I'm wondering what makes you think it was intended as a paring chisel. Regular Swan bench chisels were made that long (7-8") and were made with a rectangular cross section as well as the sloped sides cross section. If yours is rectangular in cross section, it doesn't indicate that it's a paring chisel, it's probably a bench chisel.

I have a full set of Swans, rectangular in cross section and all marked as I described, but a couple with the words "Best Tool Steel" instead of "Best Cast Steel". It took me years of watching and buying to accumulate that set (there's a difference between finding any Swan chisel and finding, for example, a 7/8" Swan chisel, marked "Best Cast steel" rectangular in cross section, and still in decent shape). The ones marked "Best Tool Steel" are not as old as the ones marked "Best Cast Steel". I've attached a picture of my set of Swans. I made all the handles.

Mike

[Older American chisels were made in factories but with a lot of hand labor. The widths should be looked at as "suggestions" rather than actual widths. I've rarely found one that's exactly the size specified.]

201432

john brenton
07-11-2011, 11:04 AM
Even if it wasn't made to be like that, it will be more useful that way (provided it's curved the right way!). The only time I use my paring chisel is for undercutting tenon shoulders, and the slight bend is invaluable. Put an appt. 20* bevel on it and it'll serve you well.

Peter Scoma
07-11-2011, 11:16 AM
Thanks for all the feedback everyone. On the back of the chisel, near where it is bent, there are a few dents in the steel so it looks like someone was prying metal when it bent, therefore I don't think the bend is original. I will try George's directions and see where it gets me. Also, can I use a torch to heat the steel instead of a hotplate? Im thinking it'll allow me to heat the area more directly.
Thanks
Peter

george wilson
07-11-2011, 12:01 PM
Mike,well,I swan! nice collection!:)

Peter Scoma
07-11-2011, 1:05 PM
Hey John, Its actually bent the other way so if the chisel is laid bevel up, its shaped like a rainbow (for lack of a better example).

john brenton
07-11-2011, 1:09 PM
Oh, OK. Yeah, that things jacked up.

Mike Henderson
07-11-2011, 1:38 PM
One more comment: For cleaning an old chisel (or a lot of other things) a deburring wheel works really well. It won't cut into the sound metal (very much at all) but it will remove the crud and stain that accumulates on old tools.

Just to forestall an argument on whether to clean old tools or leave the "patina" on them - I want my tools to look almost new so I clean them the best I can to make them look that way.

Mike

Jerome Hanby
07-11-2011, 1:43 PM
Thank god there is at least one other person who thinks that way. I like bright, shinny, and looking like new.


One more comment: For cleaning an old chisel (or a lot of other things) a deburring wheel works really well. It won't cut into the sound metal (very much at all) but it will remove the crud and stain that accumulates on old tools.

Just to forestall an argument on whether to clean old tools or leave the "patina" on them - I want my tools to look almost new so I clean them the best I can to make them look that way.

Mike

Mike Davis NC
07-11-2011, 2:03 PM
I have straightened a few old chisels with a dead blow mallet. No marks, no problems, no bother. Really easy to see exactly what is happening and to hit where needed.

john brenton
07-11-2011, 2:06 PM
If I can get it looking like new I will. I think most of us will do it if we think it'll be worth it without investing too much time. I think most of us can recognize a tool that is more valuable as a collector's item with patina than as a cleaned up user.


Thank god there is at least one other person who thinks that way. I like bright, shinny, and looking like new.

Peter Scoma
07-11-2011, 5:44 PM
Great advice in this thread, thanks guys.

Mike, will the deburring wheel remove the makers inscription??

PJS

Mike Henderson
07-11-2011, 6:30 PM
Great advice in this thread, thanks guys.

Mike, will the deburring wheel remove the makers inscription??

PJS
Of course, you want to go lightly on the logo, but, in general, a deburring wheel will not take sound metal off of the tool (or certainly not much). It will remove rust - but not pitting - and other crud, including plain dirt. When I use a deburring wheel on the area of the maker's mark, I don't linger in that area - I just make a couple of passes and let it go from there.

Mike