gas forge & little giant question

J. Neilson

J. Neilson

Joined
Feb 6, 2001
Messages
3,621
I'm finally going to brave doing my heat treating in the gas forge. To date I've always used oxy-acet. for my hardening or a small brick forge but, recently I've gotten a couple orders for blades too big for that. Before I screw things up, I figured I'd ask what psi is generally used for hardening? I know it approx. 10 for welding, 5-6 for forging, I assume it's lower for heat treat. Any tips?

Also, I'm going to order my drawing dies this week for the Little Giant (I hope). I'm really only concerned about drawing damascus billets right now. Do I need a top & bottom drawing die or just a top drawing and a flat on the bottom?

Thanks.
 
Yes you need both a top and bottom die for the "Little Giant" , on the heat treat maybe you should try "Tempil Stick's " they are sold at welding Supply shop's , i have one rated at 1500 degrees just for heat treating these thing's are like chalk but melt at the set temperature , most steel is hardened at 1500 or so so i leave it for a couple extra seconds before i quench , works very well for me .

hope this help's :)
 
J. Bring the blade up to non-magnetic and quench it in oil that is between 130 and 160 deg. Making damascus, I like to weld around 2400 deg. I run my forge at at 4 psi but I have a blower on mine. Wolf told me on his venturi forge that he had to run it at 12 psi to weld with it, his is a 2 burner.
Don't you have a arc welded?? Make your own dies. Do you have a picture of what they look like and measurements???
 
May I make a suggestion, this is a method I use myself and it will work with a blown or venturri forge. Place a length of pipe in the forge, stuff the back end with wool or put a cap on it. Direct your burner directly on the pipe. Place your blade in the pipe and watch your colors. You get a good even heat and very little decarb. I use 2 1/2" diameter steel pipe.

Ken beatty
 
Not that I claim to know anything about forging, but I thought when people suggested this method there's generally mention of sand in bottom of pipe, so you can stick tip in there and keep from overheating it?

Man I'm jealous of all y'all forging. hopefully by next summer I can move outof the city and actually get a house and setup a forge.
 
J.

I haven't tried this yet but... I have read here on the forum by many home heat treaters that they put the knife to be heat treated into a pipe that is placed inside the forge. Apparently this helps to give a more even heat to the blade (avoiding hot spots) while bringing it up to temp.

The way I've heard it described is to get a piece of pipe that your blade will fit into and cap one end. Then crimp the open end slightly to sort of seal it off from direct heat from forge. Put your blade into the pipe and then the pipe into the forge (propped up on pieces of steel or brick so that the heat can circulate around the pipe. I have also read about puting sand in the end of the pipe to protect the tip from overheating while the rest of the blade comes up to heat.

The first couple of blades I heat treated in my dragon's breath forge took me a half hour or so of constant manipulation of the blade in the forge to avoid over heating the blade in spots.

Hope that helps.

Good luck!
Rick
 
I keep forgeting to try the pipe (oldage)
I glad that that Wacko from Waco hangs around:p :p :p
Sorry MR. your OLDER than I:D :D :D
 
I tried the pipe idea. Worked great. It heats more slowly, evenly. And you can see the color of the pipe to help judge the heat.

Steve
 
Thanks guys. I'll have to try the pipe idea. Do you check the pipe for non-magnetic (I've never heard of the pipe method before)? Does anyone have any links hand for more info? I'm still not sure about the psi, lower or the same as forging?

I checked the Jim Hirasoulas(?)video on damascus since he also has a 25 lb. Lttle Giant. The reason I asked about the dies is because in the video he has a rouned drawing die on the top and a flat bottom. He also forges at 7 psi as opposed to 5 psi. I think I'll try upping my temps a bit. I don't have an arc welder George. I still do it the oxy. way. ;) I finally dug through the box of spare parts that I got with this hammer (I think I have one or two of everything) but, I did find two small flat dies about 3" wide. I think I should be able to just round these off and make a drawing die out of one or both? If that's the case the only thing I need to get is a $30.00 belt
 
J I bought a new set of drawing dies for my 50 lb Little Giant once. They are sold as a set and the bottom die is flat and the top die is rounded. If they are both rounded they are too aggressive especially for fine work like blades.

The pipe in the forge idea works great but you may need to preheat the ricasso area with your torch before installing the blade. The pipe gives a very even heat. Preheating will help keep the tip from coming up and past the critical temp. It will help to leave the tip thicker than normal also. Bring the forge to operating temp. Turn the lights out and turn your pressure down lower than regular forging. Check with a good magnet when you are even color and quench. !30 deg. quench oil.
 
J. we could make a die set up when you come down here. It can't be that hard. I make them for my press. Just bring the set that have and we could go from there.
 
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