Greetings all:

My favorite crowbar / wrecking bar is one that came with a house that
I bought. http://i290.photobucket.com/albums/l.../crowbarSV.jpg
Unfortunately this crowbar had the claw broken off by a prior owner
and it appears that someone tried to weld it back on.
http://i290.photobucket.com/albums/l...g/IMAG0231.jpg
http://i290.photobucket.com/albums/l...g/IMAG0228.jpg
I know that I could buy a new crowbar but I would like to try to
reshape the end to create a new claw - and of course I do not know the
steel grade.

My plan is to grind off the vestiges of the weld, heat to a cherry
red / straw color w/ a torch and hammer it to get the taper needed for
a claw. I think I want to let it air cool and grind in the "V" for
the nail puller on the claw and blend the outer edges of the new
claw. Next heat to cherry red and then??? quench in water?
quench in oil? stick the claw end into sand or kitty litter and allow
to cool? air cool? quench and then temper?

I have a torch set, hammers, I-beam drop for an anvil, non-contact
digital thermometer (up to 500 F, I think) & a contact thermometer (I
don't remember the range - was used to test for plugged catalytic
converters, higher than the non-contact one).

Your thoughts and suggestions?

On 7/8/2012 8:28 PM, aribert n wrote:
Greetings all:

My favorite crowbar / wrecking bar is one that came with a house that
I bought. http://i290.photobucket.com/albums/l.../crowbarSV.jpg
Unfortunately this crowbar had the claw broken off by a prior owner
and it appears that someone tried to weld it back on.
http://i290.photobucket.com/albums/l...g/IMAG0231.jpg
http://i290.photobucket.com/albums/l...g/IMAG0228.jpg
I know that I could buy a new crowbar but I would like to try to
reshape the end to create a new claw - and of course I do not know the
steel grade.

My plan is to grind off the vestiges of the weld, heat to a cherry
red / straw color w/ a torch and hammer it to get the taper needed for
a claw. I think I want to let it air cool and grind in the "V" for
the nail puller on the claw and blend the outer edges of the new
claw. Next heat to cherry red and then??? quench in water?
quench in oil? stick the claw end into sand or kitty litter and allow
to cool? air cool? quench and then temper?

I have a torch set, hammers, I-beam drop for an anvil, non-contact
digital thermometer (up to 500 F, I think) & a contact thermometer (I
don't remember the range - was used to test for plugged catalytic
converters, higher than the non-contact one).

Your thoughts and suggestions?



I suspect that all that work was done when the bar was straight and the
bends were the last things done before final tempering. I would guess
that you will need to straighten the bar back out to have a chance of
forming an adequate new head and then reforming the curve. My
experience with welding and modifying hot forged items has not been
great, I hope your experience is better.

--


___________________________________

Keep the whole world singing . . .
Dan G
remove the seven

On Sun, 8 Jul 2012 18:28:14 -0700 (PDT), aribert n
wrote:

Greetings all:

My favorite crowbar / wrecking bar is one that came with a house that
I bought. http://i290.photobucket.com/albums/l.../crowbarSV.jpg
Unfortunately this crowbar had the claw broken off by a prior owner
and it appears that someone tried to weld it back on.
http://i290.photobucket.com/albums/l...g/IMAG0231.jpg
http://i290.photobucket.com/albums/l...g/IMAG0228.jpg
I know that I could buy a new crowbar but I would like to try to
reshape the end to create a new claw - and of course I do not know the
steel grade.

My plan is to grind off the vestiges of the weld, heat to a cherry
red / straw color w/ a torch and hammer it to get the taper needed for
a claw. I think I want to let it air cool and grind in the "V" for
the nail puller on the claw and blend the outer edges of the new
claw. Next heat to cherry red and then??? quench in water?
quench in oil? stick the claw end into sand or kitty litter and allow
to cool? air cool? quench and then temper?

I have a torch set, hammers, I-beam drop for an anvil, non-contact
digital thermometer (up to 500 F, I think) & a contact thermometer (I
don't remember the range - was used to test for plugged catalytic
converters, higher than the non-contact one).

Your thoughts and suggestions?

To forge the bar you need to get it "cherry Red", or thereabouts,
which is nearly to the yellow stages. Forge to shape and finish.

To harden heat to "Cherry Red" which is nearly yellow and quench in
something like kerosene or very, very light oil. Cold water provides
the fastest quench and the greatest hardness (and the best chance of
cracking). Once the part is hardened sand or grind off a section - to
get a clean bright strip of steel where you can see the colors and
temper by heating to a dark yellow/amber or very light blue and
re-quench. Lighter colors mean a lower temperature and thus harder
tempering.