Thread: forge ideas

You might want to get some veggie oil instead of engine oil. Engine oil is very thick and wouldn't work well on a lot of steels.

Josh

Originally Posted by JoshEarl

You might want to get some veggie oil instead of engine oil. Engine oil is very thick and wouldn't work well on a lot of steels.

Josh

Oh.. I thought "thicker is better", so I got me some diesel engine oil Thank you for stopping me in time, will olive oil do? Or just any "fryer" oil?

Originally Posted by mastermute

I'm just starting out and I annealed my bar in te woodburner overnight (as per "greenpete") and for "forging" the tail I used a butane/propane hand held burner. I'm lost right now for the heat treatment, but I think it'll involve a hairdryer and a charcoal bed, some piping and engine oil...

I've used a stainless steel colander in a metal bucket, and have built a blade forge from regular red clay bricks. I use coal or charcoal to fuel it. It's very cheap and I love it for blade work.

I finally tried out my forge today, I made it this weekend with a coffee can and an asparagus can. The lining is a mixture of clay (kitty litter) and sand that was wet and rammed into the space between the two cans. The first time I just heated it up to drive off any remaining moister. The second time I tried I annealed a portion of a file. It took between 6 and 7 minutes to get hot enough that it was not magnetic. I then put the file in a can of lime to cool. I ended up doing both ends of the file. The file came out soft enough that I could hacksaw and file the perimeter to shape. I used the jth7 torch with the yellow bottle for the annealing.

Now my questions,

Is seven minutes to heat up on par with home made micro forges?

Does the yellow map gas bottle burn hotter that a regular propane bottle?

Will the jth7 torch hook up to a big propane bottle?

Charlie

Mapp gas burns a lot hotter than propane. I don't know how much, though.

I think my two-brick forge with the JTH7 torch could get that file glowing in three or four minutes. If you line your little forge with some kind of refractory coating, like ITC-100, it'll get more efficient. Does the inside of the forge glow bright yellow-orange? If not, you're just kind of containing the heat and concentrating it a bit. That's better than just using the torch in the open air, but ideally the flame heats the forge liner, which absorbs the intense heat and reflects it for more even temperatures.

Sounds like you're having fun, which is important.

Josh

Originally Posted by mastermute

Oh.. I thought "thicker is better", so I got me some diesel engine oil Thank you for stopping me in time, will olive oil do? Or just any "fryer" oil?

No, thicker is, well, different.

It depends on the steel you're using, really. Different alloys have different requirements for how they should be quenched. Some, like 1080, 1095, and W1, need a fast quenchant to fully harden. Technically, they can be hardened in plain water, but that takes some skill and raises the likelihood of cracking the blade. Water is a very fast quenchant.

The next step down in speed is thin oil. Thin oil moves around better and disperses the heat faster than thicker oil. That's why you hear guys recommending that you preheat your quenching oil to around 130 degrees F. It seems counter-intuitive, but the preheated oil becomes even thinner.

Thick oils are for steels that work best with a slower cool. O1 is a good example. If you heat it properly, it will actually harden a bit just by air cooling it. Slow oil like motor oil will work OK for O1.

Air is the next slowest quenchant. Steels like A2 are heated and then allowed to cool in still air.

Make sense?

Josh

I think the kitty litter forge looks great, hell its made of cat litter! nice blade shape too, what is the blue all over it? Dammit if i only had the money...ive been looking to try all this stuff out for years but just cant do it..i live in a very small studio apartment and have barely any money to play with at all...do you think id be able to make a fire brick forge and operate inside?

Originally Posted by JoshEarl

Make sense?

Indeed it does!

Josh
Thanks for the input. Yes it does glow, but not on the ends. There is about a 3” section in the center of the chamber that works well the ends do not get as hot. It glows for a while after the gas is shut off. I will probably end up ordering the stuff to make a two brick forge. Considering the forge cost me nothing and kept me out of trouble for the weekend I am calling it a good experiment.

Tjiscooler,

The blue stuff is layout dye, It makes it easier to scribe lines on metal.

MidwayUSA - Starrett Kleenscribe Layout Dye 4 oz Liquid

Charlie

Find some firebricks to block up the exhaust hole and that little fire will retain a lot more heat. Really, any forge is nothing more than a collection of insulation to contain the heat in one spot long enough for the smith to get the material to the temperature they wanted to get work on the material done. All you need is a smallish hole not much bigger than the steel you're putting in there.

I know smiths whose forges are great big piles of brick that get moved around and repiled frequently depending on the size and shape of the job they are doing.