Heat Treat Rig.

Rick Marchand

Rick Marchand

Donkey on the Edge
Moderator
Joined
Jan 6, 2005
Messages
9,680
Instead of buying an oven made for heat treating (like a smart guy would), I chose go through the trouble of rigging up a muffle pipe-type system for my LP Forge. I took these pics for someone and thought I would just throw them up for your critique.

I wouldn't mind seeing your set ups if you have pics, too.




My Forge...
IMG_0093-2.jpg


At 7psi it runs at about 2100F...
IMG_0092-1.jpg


Here is my "knife" muffle pipe. There is a little hole that the thermocouple fits into to give me a reading of the temperature in the pipe.
IMG_0095-4.jpg


I stop up one end to contain the heat. I took Tai's advice and threw a piece of hardwood in there to eat up the oxygen and reduce scaling. It works well but fills my garage with smoke. Most of the time I just use the pipe.(The one for swords is longer with both ends open.)...
IMG_0096-2.jpg


Here it is positioned with the thermocouple in place (the camera doen't pic up the colour too well)...
IMG_0104-2.jpg


At 1.5psi the ambient inside is 1500F...
IMG_0097.jpg


I quench in a vertical tank using quench specific oil...
IMG_0023-2.jpg






Rick
 
Last edited:
Sweet looking LP muffle rig Rick!

A little charcoal inside (instead of wood) will help with the atmosphere a bit and won't smoke so much. I use mine open air.
 
Last edited:
Thanks, Tai. You gave me some great ideas for this. That "closed end, chunk of wood" technique works like a charm... but is better left for a dedicated forging shop.... not my garage.... lol.
 
Rick, the muffle itself will help shield it a little, as I'm sure you've noticed. It tends to cut down the oxygen intake and velocity a bit.
 
Yes... it is not like it is billowing smoke or anything, just a bit to much for being attached to the house. You may have noticed that I built that particular forge on a BBQ stand. I can roll it outside when I need to.:thumbup:

I'll try the charcoal...


Rick
 
Last edited:
Very nice Rick. If you want to add anymore pics, feel free. :p

How long does it take to get to temp from a cold start?

Paul
 
Not sure Paul. I fire it up when I walk into the shop and by the time I'm ready to start forging it's up to heat. There has never been a time that I had to wait for it... so I guess it's a non issue, really.


Rick
 
Hey - my forge is a long, thin 4" diameter tube (with mizzou, satanite, and kaowool lining a pipe that is actually 6" without insulation).

It is 13" long and has a hot spot about 4" in from the entrance (I put the burner closer to the "front door" so I could heat smaller sections some times).

Finally - the question: I am making a dao-like pweld blade that is 20" long, and I need to even-out hot spots. Will the pipe really stretch out the hot zone very much, so i can get a more even ht on something longer that I have to "pump" in and out?

It looks like a good setup (I think I saw Tai do it on a vid once, maybe the woodsmaster thing).

thanks,

Kevin
 
Great setup Rick! I wish I had that idea before spent the money on a kiln.
 
kevin -the professor said:
Finally - the question: I am making a dao-like pweld blade that is 20" long, and I need to even-out hot spots. Will the pipe really stretch out the hot zone very much, so i can get a more even ht on something longer that I have to "pump" in and out?
Click to expand...


It won't spread the heat the entire length of your forge, but it will act as a buffer so the flame from the burner won't be hitting the blade, directly. It will definately be worth the trouble. In your case, I would even consider just an upside down U channel toward the front of the forge, to sheild the blade from the burner. I don't think a single burner set-up would benefit from a full blown closed ended muffle rig like Tai has.

Rick
 
Rick with a single burner (weed burner type) I can get about a 5 inch blade nice and even without pumping it back and forth. The pipe I use is a heavier gage than the one you have which helps a little. The large bushy flame that the weed burner puts out is ideal for this type of rig. I recon with 2-3 weed burners I wouldn't have any trouble with fairly long blades... I currently use charcoal for the long ones.
 
The forge of a thousand faces... lol.

This was my old weed burner forge, Tai. You could slide the burner away from the forge body to keep it from over heating.

080405044252.jpg


Before that, it was my portable MAPP gas forge for doing small knives and strikers..
forgearea.jpg


I recently converted it to a Zoeller burner type forge...
P7310297.jpg


Likewise...

My one burner propane tank forge...
080819112404.jpg


Became my two burner forge...
IMG_0020-5.jpg
 
"Instead of buying an oven made for heat treating (like a smart guy would), I chose go through the trouble of rigging up a muffle pipe-type system for my LP Forge."


... might not be very smart,... but it sure looks cool!
(cool and hot)

Out here in the desert we roll "smart guys" in jumping cactus first and then throw them in the rattlesnake pit... :)
 
Rick, Tai
thanks for info. I have a trench-style charcoal forge outdoors for swords, too. It is a pita for European types because they are so very thin that they bend too much under their own weight. I am trying to find another way without spending any more money (I am married).

I will try the channel/baffle idea, it should spread the heat some, too.

thanks,

kc
 
Rick, Me too. :)

I've used up to a 3 inch pipe with no problems and have also compressed a 2 inch.

KC, with charcoal it will also help even the heat out, but be sure to leave a little space between the muffle and the coals by suspending it through the fire. It will get cold spots if coals are touching the bottom of the muffle. Air needs to be able to circulate under the pipe. I usually drape the top with a refectory wool blanket to save on fuel. The muffle will also create a nice space for the blade and one that's easier to see into.
 
I started using a muffle for H/T about 8yrs ago, thanks to Tai. Here's some pics of my set up.

Forge with muffle in place.
PA230003.jpg


Heated and ready. The hot area is about 10" long.
PA230005.jpg


Wood added for oxy removal.
PA230006.jpg


Two of the blades I heat treated today, after 2 temper cycles. Almost zero scale.
PA230004.jpg


Mike Broach
 
Tai, is the wood or charcoal placed in the forge or in the pipe? Could one end of the pipe be welded instead of the fiber blanket?
 
You must log in or register to reply here.
Back
Top