Tools and hardfacing

Quoted text begins.Does anyone feel up to the task of explaining the process of making your
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own

Quoted text begins.firesharp chisels? I would love to be able to go to Home Depot, buy some
steel rod, and make a high quality chisel or two, but the issues of
materials and tempering are big questions in my mind. Care to share your
two bits?

Tim Bunton
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Unless you're starting with new HCS,most commonly known as drill rod,you
won't have much luck with the big box stores.Most of what they sell is low
carbon steel ,like the steel used for bolts.
Instead of buying that high priced steel from away and paying for
shipping why not start with a local source?Pick up the paper and look for
garage sales listing tools or go to a flea market.Look in the rusty old
buckets for any old cold chisels or prybars that fit your hand and have
enough length to make what you have in mind,shouldn't cost you more than $10
for a large handful.Look for old tools with good brand names
Mayhew,Williams,Ryan,Snap-on,Mac are all good names.Toss back anything made
overseas.These things are better than 3/4 there to what you need,why
reinvent the wheel?Some of the best stone chisels I own are old jackhammer
bits which have been cut to length and retempered.Most of what I have I got
at the town dump.
Anneal these old gents after rough cleaning them and checking for deep
pitting.Once soft you can cut,grind and otherwise modify at will.Leave the
final edge grinding till after heat treating(fine edges will burn and once
burnt just need to be ground back anyway).
Now break out the welding gloves,fire up either the forge or a large
torch,break out the Ballpark franks and the fun begins.Heat the cutting end
of your new tool till it's hot enough that a magnet is no longer attracted
to it,just the cutting end now.Keep a bucket of water nearby and a pair of
channellocks or visegrips to pick the hot steel up and cool the striking end
in water when it starts getting too hot,watch out for the steam.You are
wearing your glove aren't you?.Once the cutting area no longer sticks to the
magnet plunge it into a large can of oil (More oil ,more cooling and less
chance of fire).Keep all body parts well away from the top of the oil
can,submerge the tool completely and swish it around(keep a lid handy just
in case of fire).Peanut oil works for me,it has a fairly high flash point
but used motor oil will work too.When the oil stops bubbling,just stop
swishing(the neighbors will talk)and drop the tool in the oil to finish
cooling.Cook up a dog,relax,this is supposed to be fun,not like the homework
in HS algebra class!
Once cool take a file out and try it at the cutting edge.Does it skate
off and not cut,good.Now try it at the striking end,The file should cut
because it's still soft.If either of these things fail to happen start
over,the books I mentioned will help.
If you were to try and use the chisel as is it the edge would shatter
like glass.It's brittle and has no toughness or resistance to fracture.In
order to make the tool useful you need to temper it and strike a balance
between hardness and toughness.The easiest way to temper your homework is to
use your wife's oven.Wait till she's not around to see this and be sure to
clean up after yourself(now you see why I use peanut oil and not old
crankcase oil).I put my stone chisels in the oven at 550-575 degrees and
heat them for about 1/2 hour.If you polish the cutting end of your tool
you'll see the color is between peacock and blue(just past bronze but not
into a light blue) when it reaches the correct temp.Let it soak at that temp
for 1/2 hour and then let cool.
If you want to flame temper your new tool then I suggest you get an
expert to help(stay away from the pros)or at the very least buy and read one
of the books mentioned in previous posts.
Put the tool to work,if the edge chips out retemper in 25 degree hotter
steps till you get it tough enough to resist chipping.If the edge mushrooms
in use then it's too soft,reharden and temper it at a lower heat.When it
fits your hand(with alittle pipe insulation over it for grip) and cuts the
stone the way you want you get an A.
Firesharps are traditionally sharpened by heating and hammering instead
of grinding.That's a whole other level involving something called packing
and finness with a hammer you've made friends with.You gotta crawl before
you run.
When you grind the edge on your new tool think stone.The bevels want to
look more like a cold chisel and not like a wood chisel's narrow,thin
edge.Quit complainin',it wasn't that much work and you've got a tool that
you made yourself that fits your hand and does what you want the way you
want don't you?
School's out,Have another Ballpark and a beer.Forget about what the
neighbors are saying,what do you care anyway.Those guys wouldn't know basalt
from talc.Put on your loincloth,do the druid dance,they'll forget all about
the swishing.

Mainely,Bob