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I Forge Iron

Which is cooler to work with


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Which forge do you think is cooler in the shop to work with gas or coal? Right now I use coal and have to stop working in my shop when it gets into the 100's around 10 or 11 AM so my shop time is cut into quite a bit. I have been thinging of switching to gas because coal is getting harder to get where I live and just got the bug woundering if a gas forge would keep a cooler shop. Would be good to here your thoughts.
Also,I was not sure which forge sigh to put this on so just droped it here if wrong sorry.
Bill P

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That depends on your forges, and also types of fuel you use in your forge.

My gas forge heats the shop more than my coke forge, even though the forge is a side blast with a water cooled tuyere

The solid fuel for forging should be an intense localised heat rather than a radiant heat, some coal types are better than others for this

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My gas forge heats the shop up way more than the coal forge does. I sometimes use the coal in the summer even if the gas would be more efficient just to keep the shop cooler. If you really want to keep things cool get an induction forge.

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Which forge do you think is cooler in the shop to work with gas or coal? Right now I use coal and have to stop working in my shop when it gets into the 100's around 10 or 11 AM so my shop time is cut into quite a bit. I have been thinging of switching to gas because coal is getting harder to get where I live and just got the bug woundering if a gas forge would keep a cooler shop. Would be good to here your thoughts.
Also,I was not sure which forge sigh to put this on so just droped it here if wrong sorry.
Bill P


Coal because of its open hearth nature will radiate more heat into your work space. Gas forges must trap as much heat to maintain good operating pressure.

I dont use coal and wont ever though because I have asthma, dont like black lung and am not a fan of neurotoxins in coal fumes.
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Coal because of its open hearth nature will radiate more heat into your work space. Gas forges must trap as much heat to maintain good operating pressure.

I dont use coal and wont ever though because I have asthma, dont like black lung and am not a fan of neurotoxins in coal fumes.

Why would you contradict two smiths who have both coal and gas and have answered the question when you have no experience with coal?
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I have both coal and propane forges and the propane forges heat space more hands down! Think of it like running a salamander heater in the shop.

Now If I had heat issues I would build a forge surround and vent *all* the heat up a large chimney that I could.

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Gas forges do not "trap the heat" inside. They have a blast of 2000 degree exhaust going into the room. The radiant heat from a gas forge is usually far more than from a coal/coke forge also. Please don't state things as fact when they are actually uninformed opinion.

It's also more common to have a hood or chimney of some sort with a coal forge.

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At present I only run a gas forge, but in my last workshop, which I occupied for two years, I had a swan gas forge and also a very big stone built coal forge. Even with the coal forge roaring, it could never even begin to heat the space like the gas forge did.

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a coal forge of a specific volume would heat the shop just as fast as a gas forge of the same size would (it would depend on the temperature to determine the exact time it would take to reach temperature, but as far as we are concerned the times might as well be identical). It comes down to thermal energy. The more thermal energy the faster the shop heats up. The bigger the forge the more thermal energy is present. The temperature does not really factor in. think of it this way, it would take a torch much longer to heat the shop to temperature compared to a forge. Even though the torch is about twice as hot as the forge the focus of heat is about 5 cubic inches, where the forge is about 72 cubic inches. That extra volume allows for more thermal energy to be created in the same amount of time.

Thermal energy is what heats the shop and the bigger the volume the more thermal energy created. A pot of coffee has more thermal energy than a cup of coffee of the same temperature.

To simplify things a gas forge of the same size as your current forge would not keep the shop cooler. Even if you did run it cooler than the coal forge it would take longer to reach temperature, but minutes longer, not hours. The fuel is not the question but the size of the forge. Other than that you could wear lighter cloths to keep cool or get a fan.

A smaller size forge would be cooler than your current size forge.

I hope this helps

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I use a gas forge. When I made the table to hold it I put it on wheels. This way in the winter I can use it inside with the doors and windows open and stay warm. In warmer seasons I just roll it outside the door and carry the work piece to the anvil. I keeps me moving but I can forge anytime of year.

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a coal forge of a specific volume would heat the shop just as fast as a gas forge of the same size would (it would depend on the temperature to determine the exact time it would take to reach temperature, but as far as we are concerned the times might as well be identical). It comes down to thermal energy. The more thermal energy the faster the shop heats up. The bigger the forge the more thermal energy is present. The temperature does not really factor in. think of it this way, it would take a torch much longer to heat the shop to temperature compared to a forge. Even though the torch is about twice as hot as the forge the focus of heat is about 5 cubic inches, where the forge is about 72 cubic inches. That extra volume allows for more thermal energy to be created in the same amount of time.

Thermal energy is what heats the shop and the bigger the volume the more thermal energy created. A pot of coffee has more thermal energy than a cup of coffee of the same temperature.

To simplify things a gas forge of the same size as your current forge would not keep the shop cooler. Even if you did run it cooler than the coal forge it would take longer to reach temperature, but minutes longer, not hours. The fuel is not the question but the size of the forge. Other than that you could wear lighter cloths to keep cool or get a fan.

A smaller size forge would be cooler than your current size forge.

I hope this helps


Getting too technical for me. Hard to say a coal forge of the same size as a gas forge, they don't compare easily. What the experienced smiths are saying here is that "a typical gas forge heats the shop a lot faster than a typical coal forge". Even if they were the same "size" you don't usually shut off a gas forge when you pull the steel out the way you do with a coal forge. Besides, experience always trumps theory.
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Aren`t most folks in this discussion discounting the fact that most of the escaping heat from a solid fuel forge is drawn up the chimney and out of the shop while the escaping heat from a gas forge is staying in the building?
Very few of the gas forges I`ve seen or worked with are vented or run in conjunction with a chimney or hood that will pull a draft.

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WOW kind of looks like I started more then I ment to. But you all did settle my main question so I guess I'll just keep looking for coal suppliers.
No, I did not mention my shop is small 10 x 12 all metal on a dirt and paver floor. I do use 3 fans but still have to stop work around 11 and restart around 6. Just got to thinking about the difference in gas to coal and thought I would ask. It did get a bit technical though but do appreciate the effort to educate. Thanks again for all the comments but then again I really don't see the fear in getting black lung. As it takes years of breathing the coal dust to effect miners and the time I put in is just a drop in the bucket.
Stay cool all
BillP

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Hey Bob! I mentioned that in my first post! What do I win?



A big gold star on your chart and,of course my continued respect. :)
Just thought I`d mention it again as obviously most missed it when you said it the first time.
Maybe the third time will be the charm? ;)
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Bill P so build your gas forge *outside* your building with an air curtain between it and the "door" in the shop; then you just get the IR that radiates through the door.

I think that what EWCTool is saying is that BTUs are BTUs and it doesn't matter how they are generated in the shop if they remain in the shop. Of course trying to figure out if things are equivalent is difficult with a punctuated solid fuel burn vs a continuous gas burn, etc.

For efficient heating induction wins! Very little waste heat compared to other methods.

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Aren`t most folks in this discussion discounting the fact that most of the escaping heat from a solid fuel forge is drawn up the chimney and out of the shop while the escaping heat from a gas forge is staying in the building?
Very few of the gas forges I`ve seen or worked with are vented or run in conjunction with a chimney or hood that will pull a draft.


OK another thought I use a side draft hood or as it is called a "super sucker" is that still drawing more heat up the pipe as appose to a full hood? Or does this style hood allow more heat into the shop?

By the way I still have a bit of trouble getting my hood to work as well as I would like on start up but was able to improve it service over all from advice I got from another post.
BillP
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Billp, is your metal shop in the sun acting like a kind of solar cooker? If so you could put on what is sometimes called an icehouse roof. That is basicly a roof on top of a roof to keep shade on the lower roof and air flows bottom to top between them to remove heat before it goes into the building. That is how some old icehouses used to be made. Also the british had a similar double roof on some of there older landrovers. Here in this part of Ca it gets 120F in the summer. Hope this helps.
Rob

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OK another thought I use a side draft hood or as it is called a "super sucker" is that still drawing more heat up the pipe as appose to a full hood? Or does this style hood allow more heat into the shop?

By the way I still have a bit of trouble getting my hood to work as well as I would like on start up but was able to improve it service over all from advice I got from another post.
BillP



Two of the things I found helpful during start up were to use a "visor" that extended the intake of the chimney during start up.I`ve seen ones that extend out from the box and can be pushed back in when things are going well and ones that hinge so they can be flipped out of the way once the draft is established(that`s what I made).The ones that extend out can be tuned as needed.I probably should replace my hinged version but...
The other thing that helped get the draft started was to wad up a couple of sheets of newspaper in the box below the chimney,light that and let it get going and the air rising in the chimney before I light the forge fire.I primarily use charcoal so there`s less initial smoke than with coal but that`s what has worked for me.
Hope some of this has been of help to you.
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