anybody here ever done any thermite welding? I have a HUGE ol' US made
vice, and when I bought (many decades ago) it had the lower front 'tang'
triangle broken off. very thick part of the casting. like a dumbash,
back then, I held the pieces together, and nickel-rod welded it just
around the outer crack-seam, probably without preheat or postheat, too.

I'd like to start using that vice every day, so I'd like cut the old
welds, sererate the busted-off piece again, then re-do it the RIGHT way
"somehow or another"

related questions: if using thermite proves impractical for whatever
reason, how hot can I make a charcoal fire BE, in degrees, assuming I
stack some firebricks in a circular beehive sort of shape, and have it
'blower fed' air, from like a vacuum cleaner or somethin'?

what's involved with thermite, anyway, other than the danger? would I
need to make 'side and bottom' molds for it somehow, to contain the
molten stuff? out of what? there -are- videos on youtube, of guys
thermite-welding railroad tracks (and other bizarre thermite stuff, like
melting through car hoods then their engine blocks "in one pass")...is
thermite even procurable, or do I need to make my own? (thermite recipes
also online).

please, no replies from 'insurance adjuster, safety warning' or 'just go
buy a new $900 vice' type guys...

many thanks,

toolie the DIY guy :-)

So, it is a cast iron vise?

Thermite welding that I saw described, involved ductile iron.

By the way, I have appx. 2 lbs of thermite that I would love to sell
and get rid of.

i

Well, some guys in a blacksmith club in NJ used to run an anvil repair
workshop once a year. You'd pay your $150, bring your anvil and they'd
rebuild the face, etc.
They were using a large coal or charcoal fire to heat up a whole
anvil, upside down, hot enough the remove the old tool steel face plate
and then they planned to forge weld a new face plate on in it's place.
They failed to check the anvil at a critical point and pretty much
melted most of it away. Hot enough? I suspect that anvil was in the
150 pound range.
If any members of that club see this, feel free to correct or add to
this post as necessary.

Pete Stanaitis
----------------

P.S. Our club's retired railroad guru absolutely refuses to give us a
thermite demo.
-------------------------------------------------

dave wrote:
snip
related questions: if using thermite proves impractical for whatever
reason, how hot can I make a charcoal fire BE, in degrees, assuming I
stack some firebricks in a circular beehive sort of shape, and have it
'blower fed' air, from like a vacuum cleaner or somethin'?

"dave" wrote in message
...
anybody here ever done any thermite welding? I have a HUGE ol' US made
vice, and when I bought (many decades ago) it had the lower front 'tang'
triangle broken off. very thick part of the casting. like a dumbash, back
then, I held the pieces together, and nickel-rod welded it just around the
outer crack-seam, probably without preheat or postheat, too.

I would just try it and see if it holds together. You can always fix it if
it breaks.
I have a very old bench vise, Bulldog brand IIRC. I broke the front jaw
right off the slider a few years ago, and being low on cash, and needing a
vise, I used my MIG welder and ran 5-6 beads around the break. That was
probably 10 years ago and the vise is still holding together quite well. In
fact before the break the jaws were not parallel, but I was able to clamp it
together so true that when I welded it back together is is better than
before.
Greg

dave wrote:

I'd like to start using that vice every day, so I'd like cut the old
welds, sererate the busted-off piece again, then re-do it the RIGHT way
"somehow or another"

I vote for using it until it breaks.

Forced air into the bottom of hole in the ground filled with charcoal will
likely get you enough heat to preheat it for a reweld.

Wes
--
"Additionally as a security officer, I carry a gun to protect
government officials but my life isn't worth protecting at home
in their eyes." Dick Anthony Heller