Hi all, just starting out with blacksmithing. My grandfather was a Smith and so i kinda want to keep things traditional. I have many years experience in engineering and plan to start simple learning the basic skills first work my way up from there but ultimately would like to be able to forge weld and make knives and swords. So my question is should I get a gas forge or a coal/coke forge? If coal then I will build it myself. Like I said I would like keep it traditional but if gas is generally considered better I would go that route, but are gas forges good for general smithing? Are they restricted for size? Can you get bigger items in? Is coal more difficult to get started with? I will buy m ake a forge i can use for years so wont go for a starter set. All responses very welcome.
Gas is easier, especially for beginners, but coal/coke does have it’s place too. I would say this boils down to location and budget. Building a gas forge isn’t as difficult as you may think it is, I would say actually building a coal/coke forge is just about the same skill.
The first question I have for you is where do you plan on setting up? If inside, then the coal forge will require a hood to vent out the smoke. The gas forge produces a large amount of CO so you’ll also want to be sure that it gets proper air flow/ventilation.
To answer your questions:
Gas forges are great for general smithing, what you don’t get with a gas forge is localized heating. You can build a coal forge and your firepot to accommodate the size of the metal you want to heat. Also, in a coal forge, metal gets up to temperature much quicker when you are familiar with how to manage a coal fire.
Both gas and coal forges can restrict size, the different is with a coal is often times you’re able to fit the piece into the fire somehow, with a gas forge you sometimes simply can’t fit it in at all.
Coal is definitely more difficult to get started with. Gas forges you turn on the gas, light it up, and in a few minutes it’s up to temperature. Coal/coke needs constant management, you need to clear out clinkers, coke up new coal and continue to keep the coke fuel going into the firepot. Many new to coal blacksmiths also tend to burn up their metal in coal forges because it just gets that much hotter.
If I were sitting in your seat, new to smithing and wanting to forge weld and make knives/swords, a gas forge will suit you better. Knives and swords typically don’t have the odd shape that would prevent you from putting the piece into the forge. If you were making more decorative items, coal would probably be the way to go to get the isolated heat on where you need it on the piece.
I’ve made quite a few different gas forges before. If you have access to a welder, it’s real easy. If not, you can still get by, but will just have to hunt for the right piece.
Great response thank you. I think I still lean towards coal if fo no other reason than it’s versatility in terms of shape and size of individual pieces. It will be in a garage against an outside wall so a flue won’t be a problem, I’ll probably blow air into it to aid extraction as well. Still not 100% sure because as you say with a gas forge it’s a simpler starting point. But thanks for a comprehensive advice. I’ll let you know which way I go and how it goes.
Please do! And if you have any questions of course as well.
Quite honestly, coal is more fun to work with but it can be frustrating for a new smith - fire maintenance has it’s own chapters in some of the popular smithing books. That being said, I want a coal forge for the purpose of more a traditional feel, and not having the limitations of a forge cavity, if you are seeking a more traditional feel, coal will give you that feel no doubt. I have only open coal forges at my forge so I need to drag them outside, just becomes a hassle so I use gas most of the time. Once I find where I want the coal forge and flue to go inside my shop though I’ll be putting in one that is not powered, so it’ll need to be about 4’ above the top of the roof and a 12" diameter to get a good draw.
I’m not entirely familiar on what mechanical requirements you may need to properly vent, but if you are looking to vent out the side of your shop I would be aware of the coal smoke staining soffit/fascia. You said you’re an engineer, so I’m sure you’ll be able to find out what works best for you 
Have you connected with any local smiths yet? Where are you living? It might be worth it to “try before you buy”
I will take the flue above the roof line (single story garage which is separate from the house) to keep it clear of buildings. I have considered an open forge for use outside but I would then be at the beck and call of the weather, hot in the summer and wet in the winter.
I haven’t looked for any local smiths yet but I will and see if they are willing to offer any help. Due to commitments at home I doubt I will be able to start this project until September so Still have plenty of thinking and research time.
I’m in north Essex in the UK.
I had the same dilemma, when I was starting out, and knew no matter which one I picked, I would still feel it was maybe the wrong one, so I bit the bullet,
and built both, and I am glad I did, for they both have a place in Blacksmithing.
and I can do more with my coke/charcoal forge than with my Gas, but saying that Many projects I do that are small, I do on the gas,
and to be honest I would not be without either of them.
so go the whole hog, you wont regret it.
after all you can build a nice small coal/coke/charcoal forge from a Truck brake drum, then work up from there, if you like it, or sell it on for more than you paid to make it:
Grandpa.