Charcoal pack color case hardening

[BrianH]

Is it possible to  color case harden without a furnace ?
I thought I'd read before about using a wood fire but I can't find it now

[Hungry Horse]

 I'm not sure you can get the parts hot enough in a simple wood fire, without some kind of air source. I do know you can get it hot enough in a medium to large coal fired forge.

  Hungry Horse

[Smoketown]

Is this what you're looking for?

http://americanlongrifles.org/forum/index.php?topic=15508.0

http://americanlongrifles.org/forum/index.php?topic=29351.50


Cheers,
Smoketown

[BrianH]

Thanks guys
That was part of it smoketown but I thought there was one that went into more detail
Think I might just have to give it a try maybe add a small blower to the fire to keep it burning hot enough
Want to get it hot enough to get into the greys and bronzes along with the hardening

[jerrywh]

A regular wood fire with a simple draft burns at about 1500°. With the use of a blower the temp can be raised to about 3000° or more for a short time until the fuel burns up. Wood burns very fast when a blower is used.
  I have case hardened frizzens with a large wood fire in a wood stove. It works fine for a small part but a person would have to have a huge fire to do a lock and I would not recommend a blower because it raises the temp too high. If a part is quenched when it is above 1600 you will probably not get any colors but it will get very hard. If you bend a case hardened part it will crack or break depending on how long it was in the fire and what it is made of. I have case hardened a lot of parts with a propane furnace but one needs some sort of temperature monitoring devise such as a pyrometer if he expects to obtain colors. I don't post hear say. I do this stuff a lot. I have four furnaces. One natural gas 8cuft. two electric and one propane.  I made all my own furnaces and you can also. Directions can be found on the net.

[44-henry]

If I had a choice I would go with gas over electric. Color
case hardening with charcoal is hard on the elements, even when using high quality wood and bone charcoal. I used a Johnson Gas Tripple Treat furnace with Honeywell controllers  for most of the work I did and it was about ideal for the job. Lindsey publications had a fabrication manual for a rather nice little propane atmospheric forge and furnace that looks as though it would work well with  if rigged with a pyrometer. I have found much over 1550 colors start getting pretty dark and as Jerry said at 1600+ they are pretty much gone. The higher temperatures are good for general casehardening however and will give you deeper case depths in less time.

[jerrywh]

 A good way for a person with limited assets to get set up for case hardening is to find a old pottery kiln. The ones with the front opening door is best but the top loader will work.
 Acer had a neat setup for case hardening. He built a small enclosure out of fire bricks. Maybe he will tell us again how he did this.

[BrianH]

Thanks for the information guys
Right now funds are close to non existent ! Would be interested in seeing acers set up
I checked local ads for old kilns for sale but didn't find anything but I'll keep looking

[JPK]

Here's something that may be helpful.

I would like to share an experiment that came out well. I used bone and wood charcoal and packed the part as normal then placed in the fire. I didn't time it or measure the temperature other then guessing. The water is tap water nothing added. The first photo is all the equipment used.

[Goo]

If I had a choice I would go with gas over electric. Color
case hardening with charcoal is hard on the elements, even when using high quality wood and bone charcoal.

Have you tried bone charcoal from the aquarium supply or do you make it yourself ?     

[jerrywh]

 I know that charcoal pack is supposed to be hard on the elements but I have been doing this in my electric oven for over 12 years and so far no problem. I think the problem with the elements is caused by using charcoal that is not completely charred or dirty.

[BrianH]

Do you have an opinion jerrywh is one heat source better than other ? are they both about the same cost to build