Question about rehabing my abused chisels

[Dave Houseal]

Once upon a time when I didn't know any better, I tried to sharpen my plastic handled Stanley bevel edge chisels with bench grinder.

Long story short, I trashed them pretty good, and definitely overheated them. They've since been replaced with a set of Crown bevel edge chisels, which have been great for me, but lately I've realized that one set of bevel edge chisels isn't enough.

To be sure there's nothing special about those stanley's. They're maybe 10 years old. Probably not that great of steel and the plastic handles aren't all that great. But there are times I'm doing carpentry work that I'd rather not expose my good chisels too, and I really would like to have a skew.

So I started reading about hardening and tempering. Even if it doesn't work out these chisels are already ruined, what's the worst I could do :p

So my first question is about the handles. I'm kind of assuming that they are going to melt when I heat the chisels to harden them and if not falling apart then they probably won't survive the oven for tempering. So...do they have to go? Are they going to melt if I try to keep them in tact?

Also what kind of steel am I likely dealing with? I'm guessing its a standard carbon steel which from what I've read should get an oil quench and be tempered at between 300 and 325 degrees.

Any other things I should keep in mind? Or is it not even worth bothering with these things?

Thanks!

[Sean Hughto]

I can't imagine that you overheated any more than the first what, 1/2 inch maybe at most? Some patient and proper grinding can set this right without resort to tempering and hardening alchemy.

[Dave Houseal]

Well that certainly sounds a heck of a lot simpler. Is there a good way to know once I've ground enough off that I'm into the metal that's still hardened properly?

I guess if it still doesn't hold an edge when I'm done I haven't gone far enough.

[Jay Bush]

Not saying that It cant be done; but having worked with steel, I know getting perfect results is difficult enough in an industrial setting let alone attempting to quench, temper, and anneal at home. Sean has the right idea. I would just grind (using proper technique) until the chisel was capable of holding an edge. If you really wanted to get fancy and had access to a hardness tester, you could measure the hardness every 1/8th inch from the edge until you found where the damage to the heat treatment ends.

[Sean Hughto]

I've usually had pretty good luck simply by grinding off the blued area plus a bit. Odds are that you didn't generate temper ruining heat at a grinder much beyond the existing bevel, for example. Grind that bevel away, and once square and fresh, patiently create a new one with plenty of quenching (maybe only use the grinder to remove the bulk and use whatever method you now prefer in the way of stones or whatever to get them sharpened and honed.

[Dave Houseal]

They were really only blued out at the tips...maybe I'll get the grinder out and give this a try tonight.

[Jim Koepke]

Sean is giving good advice.

Mine is that if these are to be the beater chisels… Get a good edge on them and then if it doesn't last, just hone them again and again until they do.

Also, you will find after awhile you may want even more chisels for different work. I have a few Craftsman chisels that I was going to get rid of, but they seem to work fine so they are now my better beaters.

It is possible, but hard to have too many chisels.

jtk

[Dave Houseal]

Sean is giving good advice.

It is possible, but hard to have too many chisels.

jtk

Hahaha...this is the conclusion I'm quickly coming too. After chopping through mortises with my bevel edge chisels for a Christmas present I was working on, I am now the owner of a set of narex mortise chisels, and after testing those out I couldn't believe what I was missing.

I'm working on learning dovetails now, so I can see myself needing a 1/8" or 3/16" bevel edge OR both, and I'd like to convert the 3/8" stanley to a skew to try that out.

The more I learn apparently the more tools I need.

[Paul Saffold]

Yep, that's a fact.

The more I learn apparently the more tools I need.[/QUOTE]