Wednesday, July 27, 2011

BRING OUT YOUR DEAD - Repairing a smashed chisel socket.

Joe sent me a chisel. 
Why did Joe send me a chisel? 

Well Joe had a problem. 
On the 'Old Tools'<>; mailing list of which I am a proud member Joe sent out the following:
I've got a 3" slick (Ohio Tool Co) with a socket that is beyond
de-mushrooming. It needs the TLC of a skilled blacksmith. Someone on
this list actually has repaired/replaced such a socket and posted about
it - with pictures no less. But I can't find the name/site. I really
have no need for a 3" slick, but it's sitting there mocking me and that
just has to stop.

Anybody out there with the tools and skills to rebuild this thing for me
(at a reasonable price please!)?

Here's a couple pics of the current damage. There's 1" of socket
remaining, and the curled over end of what used to be another 1/2" or
so. The fat stuff looks to be some sort of cloth tape and although my
blacksmith skills are severely limited, I'm guessing that it holds no
structural value and could probably be removed.

Joe M.
Because the Old Tool List is a great collection of guys and gals who share their opinions, ideas, and a vast quantity of helpful advise with anyone who asks and sometimes before they think to ask Adam replied:

I sent this link to Joe this morning, but forgot to copy the list.  Dave
Nighswander posted a great series of pictures on a socket chisel repair
job (one year ago today, strangely enough):

The links are split in the archives, so here's the photo page on GIC:

Port Angeles, WA

Joe sent me a chisel. 

Actually Joe sent me two chisels. The top one is the Ohio Tool 3" chisel. The design is what is called a firmer chisel because it has squared off edges. The tool is made from wrought iron and a hardened tool steel blade that is welded on the business end. The bottom one is a hitchhiker that Joe sent along as a practice piece.

How does a person go about repairing a mushroomed socket chisel? First I find out what it's supposed to look like by verifying what it is.

Then I try to match it up against a pattern that is similar.

In this case it is an old unnamed chisel that resides in my chisel drawer. The the remaining section of socket on the Ohio Tool matched the taper on the no name socket. I had my pattern.
Then I need a mandrel to form the socket over. After looking through my various neatly arranged collections of miscellanious iron shapes, the scrap pile, I determined that I didn't have any object with a matching taper. I did have a rather large bar of iron that used to be a car axle. See dear I told you I would need it someday. It just needs to have a special taper on the end. Not to worry, I have a lathe and I get to claim another reason for owning said lathe.

But first I have to shorten the bar enough to fit in the lathe. I made a rather pointed argument about my feelings for hacksaws in another forum. (Old Tools) Put on your safety glasses the sparks are flying.

Now all I need to do is chuck up the piece, center drill it, and turn it to the proper size and angle.
If you are really fascinated with South Bend Model C 9" lathes then go here:
Otherwise go to the next picture.

Now all it needs is a 1" square shank welded on so it will fit in the hardy hole in the anvil or in the post vise in this shot.

With the mandrel made I heated the mushroomed area with an acetylene torch. The size of the chisel dictates the amount of heat needed to get the socket up to yellow where it can be reshaped. With this big of a part that little hardware store propane torch just won't cut it. On a really big object the gas forge will work quite well. If necessary the coal forge can be used but in this case it isn't needed.

(Sorry guy's I'll have to fire the cameraman. He forgot to turn it on for this step.)

After heating the curled edges of the socket the metal is pulled and hammered back into a semblance of it's original shape. Sometimes there is enough metal left to reform the entire socket. Sadly in this case there wasn't. The material had been stretched and hammered over the years until there was only 3/4" of usable socket left. 
A donor piece was found, I told you I was going to need that, and welded on the chisel. Before you ask: Yes, it could have been forge welded. I'm not a fanatic about blacksmithing with only traditional tools. Yes I do have a coal forge, anvil, post vise, tongs, hammers etc just like they had in 1860. I also have arc welders, torches, lathes, and abrasive cutoff saws. I use what works.

After heating the two welded parts, hammering them into shape, grinding and filing the socket, the chisel is back to working condition. 

I sent Joe back his chisel. 

Let's see I think I can find something else to do but then jobs just seem to show up. Maybe I'll wait and start in the morning.

1 comment:

  1. You do great work and I've got the 3" slick to prove it! Thanks again.