Subject: airhammer points

From: [email-masked]
Date: Mon, 22 Apr 1996 09:19:27 -0500

I was recently asked to sharpen some points. They are made by Brunner &
Lay, about 7/8 square with a tapered shank. I went over to the Thomas
Register site to get their phone number. I talked to Bill down at Brunner &
Lay. He told me that the points are made of 1045. They use a one step heat
treating process. After forging out the point reheat and quench in brine.
After a quick quench take out and allow to air dry. There is enough reserve
heat to temper. Regrind the edge and you're done. He advised moving the
heat line on the second heat to avoid a fracture line.
  There are a lot of these points out there if you are looking for that
kind of work. Check cement contractors, rental outfits and the like. Also
when they are worn down beyond use they will often give them to you. A
great source of good steel for shop tooling. Have Fun.

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From: [email-masked]
Date: Mon, 22 Apr 1996 14:58:33 -0500

>     Please explain, you said that it was a one heat process and then
>     advised to move the heat line on the second heat. What is the purpose
>     of the second heat?
>
>     Bob Ehrenberger
>
>
>Subject: airhammer points
>
>heat to temper. Regrind the edge and you're done. He advised moving the heat
>line on the second heat to avoid a fracture line.

The heat treat process is one step using reserve heat as opposed to
re-heating for tempering. The forging process may take more than one heat
depending on the condition of the chisel. Move the heat line for each heat
to avoid a fracture line.

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From: [email-masked]
Date: Mon, 22 Apr 1996 23:32:47 -0400

I have been very interested in sharpening air hammer points locally as I have
a big enough power hammer and the tooling to do them quickly, but I have two
questions:

I've been told that air hammer points are S7 (or something similar which air
hardens).  The same source of info told me NOT to quench them - just forge to
shape and let air-cool, then finish grind.  Care to comment?

The second thing has been touched on before, but I wonder if there is a
liability issue.  If a point breaks and a sliver goes in someone's leg, are
you liable?  Do you care? Do I worry too much?  I'm sure that during a trial
the original manufacturer of the point would question forging and heating
techniques used in the average shop.  I am not a full time 'smith and my
insurance agent told me that I'm NOT covered if I get sued.  I hate even
asking this question, but it is the society that we live in.

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From: [email-masked]
Date: Tue, 23 Apr 1996 13:39:53 -0500

>asking this question, but it is the society that we live in.

   Call the manufacturer for information on the type of steel. I got a
handout from Brunner & Lay several years ago that I would be glad to post
if people are interested. I was surprised to hear Bill at Brunner Lay say
that they were 1045 also but I believe him. As to liability I am sure you
could be in a bad spot if there was trouble. How much would this kind of
insurance cost?

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From: [email-masked]
Date: Tue, 23 Apr 1996 20:57:38 -0400

LliseW, on your first question, my experience with S7 has been really good,
I have several heavy duty punches made of it, and they work very well even
when hot, and yes, they do air quench.  Dip them in water to cool will result
in a thin case depending on the temperature when it entered the water.  By
the way, it's tough to get the head of the tool 
soft enough, use a particular hammer when you use the punch, as it may ding
the face
of your favorite forging hammer, resulting in little pimples on your work
later.
   To your second point, yes you are liable if a fragment injures someone,
and your insurance agent was correct, you won't be covered.  There are
several smiths who have taken on this type project, to their detriment, even
ruin.  I wouldn't touch one except for my own use for any money.  Let the
manufacturer assume and accept the liability, life is too short to subject
yourself to sleeplessness and possible ruin.
  There are probably warning stickers you could apply after you finish, but a
stamp like that seen on hammer heads and chisels nowdays would be better.
 They are expensive, and marking S7 with one would take enormous force, even
hot.  There are too many negatives, it's not for me.  Follow your gut
feeling.

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From: [email-masked]
Date: Wed, 24 Apr 1996 11:35:27 -0500

>hot.  There are too many negatives, it's not for me.  Follow your gut

  I called back to Brunner & Lay the manufacturer of the chisels I am
sharpening. He re-confirmed what he had told me earlier, that the chisels
made by them are made of 1045 and have been for 20 years or more.
  I also called an insurance office near me. The agent said he would write
a liability policy for a someone making less than $10,000 per year (a
reasonable figure for a part timer) for about $400.00 per year. This would
be $100,000 coverage.
  Whether an individual wants to take on this job is of course a personal
decision.

---

From: [email-masked]
Date: Thu, 25 Apr 1996 09:40:42 -0500

>        I think you're right to worry about liability. If you temper
>economically by just heat hardening the point (S7 is also a water hardening
>steel) you're at high risk for creating a fracture line right at the edge of
>the quench. If you don't temper back you've created an almost certain risk
>of small splinters flying off. This isn't a knife. This thing is going to be
>exposed in public to massive impact forces. When the thing breaks up -- as
>you know it's going to do --- and sends steel shrapnel into expensive body
>parts you are liable.
>        If your customer won't accept it back annealed, hire a lab to do the
>hardening and tempering and pass the cost off to the customer.
>        I won't touch them or truck chain tie downs for the same reason.
>
>                John W. Pollins, III
>                Speaking as a Board Member of both ABANA &
>                The Pennsylvania Trial Lawyers Association

  I think you are right to worry about liability also. You can buy
insurance that will protect you at fairly affordable rates.
  As to the use of S-7 in these tools I am not convinced (with all due
respect). Have you called the manufacturer? Brunner & Lay are not the only
maker of these points but they are one of the biggies, at least of the
points I see in my area (name stamped on shank}. They use 1045. I think
1045 is cheaper than S-7 and if it will do the job I would be surprised if
others were using S-7, but again its easy enough to find out.
  When I sharpen these points I try to err on the side of caution. I would
rather that they be to soft than to hard and I think the customer would
agree.

                                              Speaking for myself ))

                                              Bob Schade