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Charcoal Vs. Propane as foundry fuel

Are you about to build your first foundry and wondering whether to fuel your furnace with charcoal or propane? I've spent considerable time using both propane and charcoal as fuel for my foundry so I'm convinced that I can give a non-biased accurate judgment about the pros and cons of each. The beneficial attributes are in green text, while the drawbacks are in red text. Aug/17/2002

A charcoal fueled furnace Vs. A propane fueled furnace

Charcoal
Propane
You must first get the charcoal burning which can be smoky at times, lighter fluid is helpful lighter fluid is helpful but those sheet metal igniter devices for barbecues are best. But it still takes about 5 minutes. Propane is ready to go as soon as you set the burner in the furnace and open the gas valve. No wasted time.
Charcoal must be loaded around crucible and adjusted occasionally to keep the crucible centered. The heat from propane flames enter the furnace and twists around the crucible filling the chamber.
Charcoal does hold crucible centered after it's loaded. Propane does not hold the crucible in place leaving it liable to tip over.
Produces some smoke in the very beginning and sometimes needs more fuel to be manually added. Burns cleanly all the time and no manual reloading is needed during furnace run since new propane enters the burner constantly.
Barbecue charcoal is usually only available during the summer, making it hard to melt metal during the winter unless you stock up. Propane is usually available year-round since it's used for more than just gas barbecue grills.
Charcoal is pound for pound a lot cheaper than propane. Propane can be expensive even if you exchange tanks with a dealer (here in NY at least).
You can make your own charcoal in your backyard! If you can make propane in your backyard you get plenty of respect from me...
Barbecue charcoal briquettes can sometimes last for several crucible loads. Once the propane leaves the burner it's gone with the wind...
Hardwood charcoal (not the briquettes) can melt iron but you need a special furnace (cupola). Build a big burner and you can even melt iron with propane!
Charcoal furnaces are pretty quiet. Often the blower is the loudest part. Propane burners aren't disturbingly loud but they sound like a small jet or a big plumber's torch.
Charcoal leaves a lot of ashes to be cleaned away. With propane you don't have to clean up jack... it's clean heat.
A charcoal furnace requires no special hardware and can be rigged together very quickly from junk. You have to build or buy the propane burner and you might need a regulator. You need the propane tank also!
If you run out of charcoal you can toss in some wood (if you don't mind the smoke). If you run out of propane... time to open your wallet and start the car.
Based on physical laws charcoal transfers heat to the crucible faster since it's in direct contact. Therefore it is more efficient. Propane burns and heats the air around the crucible, and the air doesn't transfer heat as quickly making it less efficient.
Summary:
In my opinion charcoal is a much more economical fuel and since it transfers heat quicker it is more time efficient also. However propane is a heck of a lot more convenient and much neater. For that matter alone I find it hard to fire up my charcoal foundry even if I've run out of propane and can't make it to the store to get a refill or tank swap. A propane foundry can really spoil you!

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