saintjohnbarleycorn Posted July 10, 2011 Share Posted July 10, 2011 I found a crowbar with my lawn mower, and it bent one of the nail puller part, so I have to heat it bend it back and harden and temper it. Is possible with a simple setup. I can't heat the whole thing up, its a 40" long one, am I going to put a hard breaking point on the bar if I only heat and temper one end that I can fit in the gas forge? I don't think that I can just hammer it back, with out breaking the prong, I would guess it work hardened when it bent. Or should I just call it a loss and buy a new one? thanks for the help. Quote Link to comment Share on other sites More sharing options...
edge9001 Posted July 10, 2011 Share Posted July 10, 2011 Thats a good question. I have a crowbar with one side of that same end broken off. I want to reshape the end so I can fix it, but I have the same concern. ok guys what do you think? Quote Link to comment Share on other sites More sharing options...
Marksnagel Posted July 10, 2011 Share Posted July 10, 2011 40" crowbar with a broken foot? Hmmmm. If you do chalk it up as a loss I think it would make 5 nice 8" punches. Mark <>< Quote Link to comment Share on other sites More sharing options...
Old N Rusty Posted July 10, 2011 Share Posted July 10, 2011 Did the lawnmower survive? Quote Link to comment Share on other sites More sharing options...
bigfootnampa Posted July 10, 2011 Share Posted July 10, 2011 When I make or alter pry bars I generally leave them "as forged". They should NOT be hardened... thus no need for tempering. Normalizing might be useful when working on an end with thin cross section, to counter any unintentional air-hardening (but I rarely do it). It is better to use a higher carbon steel and leave it unhardened when more strength is needed... or just to use thicker steel. You would NOT want any brittleness in a pry bar. By keeping heats minimal and working the material to shape quickly you will keep grain growth down too and have a good working tool. This approach has always been satisfactory for me anyway. Quote Link to comment Share on other sites More sharing options...
son_of_bluegrass Posted July 10, 2011 Share Posted July 10, 2011 If you're going to heat treat a pry-bar or crow bar you just want the working end hardened then drawn back like a spring. You don't want it hard enough to chip if struck. And it will actually work better if just the working end is heat treated. ron Quote Link to comment Share on other sites More sharing options...
saintjohnbarleycorn Posted July 10, 2011 Author Share Posted July 10, 2011 Thanks , that sounds do able for my skill level. I am guessing just use a torch on the end low cherry red bend it and put it in vermiculite. sound reasonable? Quote Link to comment Share on other sites More sharing options...
bigfootnampa Posted July 20, 2011 Share Posted July 20, 2011 Thanks , that sounds do able for my skill level. I am guessing just use a torch on the end low cherry red bend it and put it in vermiculite. sound reasonable? NO! That would anneal the end that you want to harden and strengthen. You would quench it in oil (NOT vermiculite) and then bake it back to about 900 degrees Fahrenheit (greasy stick method). Quote Link to comment Share on other sites More sharing options...
double_edge2 Posted July 20, 2011 Share Posted July 20, 2011 I do lots of crow bars, usually tip only , harden in oil and temper to peacock, after reshaping. The most basic setup will achieve this no probs .. Quote Link to comment Share on other sites More sharing options...
saintjohnbarleycorn Posted July 20, 2011 Author Share Posted July 20, 2011 thanks I will do it that way. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted July 20, 2011 Share Posted July 20, 2011 Note that this depends on what alloy the crowbar is made from. Generally they are a medium carbon steel; but they can be high carbon or even Titanium---remember the russian Ti crowbars sold about a decade ago? I'd spark test it first and adjust the tempering temp based on that lower for a medium carbon steel and higher for a high carbon steel. Quote Link to comment Share on other sites More sharing options...
saintjohnbarleycorn Posted July 20, 2011 Author Share Posted July 20, 2011 I will spark test it. I don't think it is anything fancy, it was an ace hardware, about 10 years ago. thanks for the help. Quote Link to comment Share on other sites More sharing options...
Frank Turley Posted July 24, 2011 Share Posted July 24, 2011 Assuming that you sparked and found it to be medium or high carbon, I have a suspicion that the entire crow bar is hardened and tempered.. You can protect the part behind the claw by wrapping with a wet rag leaving only the claw protruding. Another way is to use Heatstop or Heat Fence, a putty like material designed to keep heat from traveling. Once you've done that, the claw can be heated, straightened, normalized, hardened, and tempered (to perhaps a pale blue tempering color. Quote Link to comment Share on other sites More sharing options...
edge9001 Posted July 30, 2011 Share Posted July 30, 2011 I did my crowbar repairs yesterday. I heated the end I worked on till above magnetic, quickly dunked in water until the surface just started losing color, but mostly was still some shade of cherry red and then set aside to finish air cooling. When i tested it out, it seems to work just fine. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.