Charcoal,coal and Gas?

Not that I have heard or read. Of course you might be to do certain things with charcoal that might be different or more difficult with gas. Perhaps case hardening??
 
There is more to case hardening than charcoal. In fact most case hardening kits are set up to use in either a gas or electric kiln.

Charcoal and Coal/coke can be used very effectively for forging. However the chances of burning your steel is much much greater using solid fuels. I have only burned a piece of steel a couple of times in a propane forge. While a second of in-attention will destroy your project with solids. There are ways of imparting carbon into the steel using solid fuel, however they are far to complex and ineffective for the average knifemaker.

Positives to solid fuels over gas

can get hotter faster
concentrated heat
easier to shape fire to fit project

Drawbacks to solid fuels

Expensive
Dirty
gets hotter faster thus more easy to burn steel
clinkers
bigger learning curve

The only real drawback using gas is the remote possibility of an explosion. Though I have heard of fires caused by negligence, I have not heard of a knifemaker blowing themselves up.

I started on a coal forge and have used coke and charcoal. I am glad I have the ability to use the solid fuels. I do not intend to ever use them again unless I have to at a demonstration or the like.
 
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In my opinion, gas has it hands down over solid fuel.

Start up time and maintenance are near zero for gas, and considerable for coal/charcoal/coke. You don't have to clean up and dump dirty ash and clinkers with gas, either.

You can HT reasonably well in gas, but it takes some skill and finesse to do it with coal. Part of this is the fact that with gas you can see the blade, and remove it easily as often as you wish for examination. With coal, you may have to re-build the "dome" you made each time you take out the blade....and you can't see how hot the blade is when in the coals.

Smoke and smell are also not conducive to running a cola forge indoors without some dedicated insulated chimney work (this can get expensive). Indoors or outdoors, you may not be allowed to run coal in the city. Gas can be used inside in a shop with good ventilation, and can be easily rolled outside on a cart. Coal forges are not particularly portable.

Coal has a smell that is nostalgic to smiths, but offensive to most people. No one will know you are running a gas forge by the odor. A gas forge makes a bit more noise than a coal forge, but unless it isn't running right, the noise isn't much at all. A lawn mower makes a hundred times the noise.

While no vapors from combustion are good to breathe, gas is much cleaner as far as air quality and lung health. Properly tuned, the output of gas is basically CO2 and water vapor. Besides the soot and other noxious gasses that make coal smell bad, it releases a lot of CO.

While you can build a simple coal forge from a brake drum with a little scrounging and some welding skills, the cost of a good coal forge with proper blower vs. a gas forge isn't significant. A top notch PID controlled gas forge can be built for about $200-300. A proper coal forge with a VS forge blower or hand crank would cost about the same.

Fuel is arguable, but I think for most of us propane is cheaper...and certainly more available. It is also a lot easier to store a months worth of propane in a #100 tank than it is to store a months worth of coal.

Things can go radically wrong when forging in coal much easier than in gas. Look away for one moment, or turn up the blower a tad too high, and the blade may become a Fourth-of-July lump if steel slag in seconds ( those who have used coal know what I am talking about). With gas you really have to try hard to ruin the steel in normal blade forging.

About the only advantage in a coal forge is the ability to have concentrated heat. You can build this easily by making a dedicated one burner blacksmiths open style gas forge for probably $50. One of these is a very useful tool in a metal shop, as it allows only part of something to be heated. I consider it sort of a hands-free torch. (here is an example - http://www.ebay.com/itm/Forge-Frees...001?pt=LH_DefaultDomain_0&hash=item2c8196e941 )
 
I hope this is not derailing but further discussion on the pros and cons. Currently I run a coal forge, and to me the fuel I think is cheap. Currently I get 40lb bags for $6.00 a piece and they last about 1.5-2 weeks per bag. Now I use it for making hooks rr spike knives. How long does a 100# tank last on say 5hrs of use a day?
 
If you run 1 or 2 days on a 40lb bag of coal you have a really small fire. A 40lb bag of coal, if we can find it runs about $20 on the west coast. You also have to make sure it's the right coal. Too much sulfur will ruin steel. Last time I ran coal making Damascus I went through almost 100lbs per day.

Though I have not made one yet, a forge like Dave Lisch runs lasts 60 hours on a 100# tank. Mine only lasts 18 hours right now. I started building my new one yesterday. Still even at 3 days per bottle at $60 it is cheaper to run propane vs coal. But I have not looked for coal in probably 15 years so no telling what it costs now.
 
Just did a quick search, coal will cost me over $1/lb. Guess it is nice to live near a coal field.
 
I get my coal out of west virginia which is little over 2hrs away. So its running $.15 a pound. I will just stick with it for now.
 
Another aspect, especially in southern Ca. There are air quality laws that prevent one from using solid fuels. I know in L.A. area it is illegal. Heck there are days you can't even use the BBQ.
 
There is coal and there is forging coal. Pocahontas #3 is the preferred forging coal.

I honestly don't know how long a 100# tank lasts me, but it is a good while.
 
I can get 50lbs of coal for $20 or a bbq propane filled for the same amount. I don't know which will last longer for blade work because I have only used crappy coal forges, but that is the apples to apples price comparison for me. Despite what ended up being cheaper I, personally, would chose gas over coal every time for all the reasons Stacy mentioned.
 
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