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Jlinner

Burner Placement

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Question:

Can you do a layer of refractory cement in between each layer of wool?

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You could, but why would you?  The cement is only there for wear resistance, both mechanical and flux.  Otherwise it's just a heat sink.

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2 minutes ago, Alan Longmire said:

You could, but why would you?  The cement is only there for wear resistance, both mechanical and flux.  Otherwise it's just a heat sink.

Cuz I do a lot of weird stuff... LOL 

Just curious

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3 minutes ago, Alan Longmire said:

You could, but why would you?  The cement is only there for wear resistance, both mechanical and flux.  Otherwise it's just a heat sink.

Do you think it would trap more heat like barrier?

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It also helps lock in the pesky, and unhealthy, fibers from the wool.

Think of it as a high temperature sleeve.

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Hmmm 2 layers of cement, I have a two 20 pound bags of Bubble Alumina so I might try it.

I would like everyone to chime in here with opinions.

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5 minutes ago, Jlinner said:

Do you think it would trap more heat like barrier?

Think of the wool like the loft in a down jacket. The more uninterrupted loft of the down you have between the inner and outer shells of the jacket, the better the insulation works.

Don't worry, the rigidizer you put in already won't have a significant, if any, effect.

Edited by Vern Wimmer
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2 minutes ago, Vern Wimmer said:

Think of the wool like the loft in a down jacket. The more uninterrupted loft of the down you have between the inner and outer shells of the jacket, the better the insulation works.

Don't worry, the rigidizer you put in already won't have a significant, if any, effect.

I like that analogy.

I'm just trying to find any disadvantages to adding a cement layer between each wool layer and cant seem to think of one.

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8 minutes ago, Jlinner said:

I like that analogy.

I'm just trying to find any disadvantages to adding a cement layer between each wool layer and cant seem to think of one.

Vern just gave you one: it will reduce your efficiency.  Don't do it if you want best results.  If you want to play and don't care about having a slightly worse set-up, go for it.  

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1 minute ago, Jerrod Miller said:

Vern just gave you one: it will reduce your efficiency.  Don't do it if you want best results.  If you want to play and don't care about having a slightly worse set-up, go for it.  

Oh, I think I read that wrong then... Thank for the clarification.

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Adding all of that refractory (2 layers of wool and a cement layer) is not ideal IMNSHO. Refractory wool and cement only starts to reflect the heat efficiently after it has come up to temp itself. The thicker you make the lining, the longer you have to wait to come up to heat, and there's no real evidence that all that refractory really helps much at the temps we typically use. I only have a single layer of 1" wool covered with about 1/4" of Satanite and my forge gets to welding temp in less than 7 minutes.

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51 minutes ago, Joshua States said:

Adding all of that refractory (2 layers of wool and a cement layer) is not ideal IMNSHO. Refractory wool and cement only starts to reflect the heat efficiently after it has come up to temp itself. The thicker you make the lining, the longer you have to wait to come up to heat, and there's no real evidence that all that refractory really helps much at the temps we typically use. I only have a single layer of 1" wool covered with about 1/4" of Satanite and my forge gets to welding temp in less than 7 minutes.

That is going to be quite a news flash to Anvilfire and all the others, including some professional forge builders who suggest 2" of "wool"  plus a costing of refractory as a minimum.

In the case of our OP here he has a large enough forge body, and certainly more than enough burners, (and given that factor alone) to make the second inch of wool negligible in heating time and a good idea for keeping the heat from 5he burners where it belongs-on the inside of the forge 

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11 minutes ago, Vern Wimmer said:

That is going to be quite a news flash to Anvilfire and all the others, including some professional forge builders who suggest 2" of "wool"  plus a costing of refractory as a minimum.

Yep. It sure would be. That's what happens when a lot of people start taking common practice and regurgitating it over and over again without actually doing some simple testing and experimenting to find out if less is more. It will work fine with all that stuff inside it. I just don't think it is necessary.

11 minutes ago, Vern Wimmer said:

In the case of our OP here he has a large enough forge body, and certainly more than enough burners, (and given that factor alone) to make the second inch of wool negligible in heating time and a good idea for keeping the heat from 5he burners where it belongs-on the inside of the forge 

Probably right, but as I look at that forge, I start to think that it's likely over-powered for its size. My prediction is that after a few uses, he will probably turn off the center burner or take it out entirely. I may be totally wrong but it looks to me like it has one too many burners and most of the heat is going to be pushed out the doors making the dragon's breath difficult to deal with. Especially once he chokes down the inner volume with an extra inch of wool.

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Given that the burners he is using can be throttled down the breath of the dragon can be controlled while still giving the desired results . But, as you point out, he is "overburnered" and that gives me concerns about the potential temperature of the shell and the plumbing. I have never seen a forge of that design running three burners, of that size, with only 1" of blanket.  There is another side to the word "efficiency" , that is fuel consumption. I agree that he will likely decide that 2 burners will suffice. This will be more efficient and probable with a smaller interior space anyway.

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3 minutes ago, Alan Longmire said:

That's just an awful lot of burner for the volume.  

Even for welding you think?

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More burners means more potential for an oxidizing atmosphere, which is definitely not conducive to welding.  A pair of 3/4" T-Rex burners would be able to melt steel in that forge.  If your burners are as efficient, act accordingly.

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10 minutes ago, Jlinner said:

Even for welding you think?

I have a single burner "Chili forge"  that has the less efficient old style burner. It is around 1/2 or a bit more, than the length of your forge and probably 3/4 or so of the diameter of yours. I can get to welding temp with it. Maybe not as fast as some would be happy with but I know that if it were the size of yours with two of the new "El Diablo" burners, like yours, it would reach welding temp about as fast as I'd want to work. I am not sure that a third burner would do much more than create dramatic Dragon's Breath and heat up the shop.

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19 minutes ago, Vern Wimmer said:

I have a single burner "Chili forge"  that has the less efficient old style burner. It is around 1/2 or a bit more, than the length of your forge and probably 3/4 or so of the diameter of yours. I can get to welding temp with it. Maybe not as fast as some would be happy with but I know that if it were the size of yours with two of the new "El Diablo" burners, like yours, it would reach welding temp about as fast as I'd want to work. I am not sure that a third burner would do much more than create dramatic Dragon's Breath and heat up the shop.

I think I'm going to roll with it the way it is for now and test it the way I have it setup and see what's up. I have spent a ton of time on it and haven't even heated a piece of metal up yet. If it turns out I need to delete the middle burner I will do so because I do not want to cause my work piece to be damaged.

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Good plan. It does no harm to try and you will have options. I like options myself.

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Just now, Vern Wimmer said:

Good plan. It does no harm to try and you will have options. I like options myself.

Yeah you know, might as well try.

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Would make any difference if I added a 2 inch layer of wool to my existing 1 inch or just add another 1 inch layer?

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1 hour ago, Jlinner said:

Would make any difference if I added a 2 inch layer of wool to my existing 1 inch or just add another 1 inch layer?

I was told you can but its a world of diminishing returns in other words you wont gain as much for adding the 3rd layer as you will by going from one inch to two.

Sounds like at least one person here thinks less is more when it comes to wool.

I have 2" and my shell and burners get real hot....mostly after the forge is off. It was real apparent real fast why they came with quick disconnect fittings.

 

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2 hours ago, Kreg said:

I was told you can but its a world of diminishing returns in other words you wont gain as much for adding the 3rd layer as you will by going from one inch to two.

Sounds like at least one person here thinks less is more when it comes to wool.

I have 2" and my shell and burners get real hot....mostly after the forge is off. It was real apparent real fast why they came with quick disconnect fittings.

 

Exactly. If just adding more insulation to something increased efficiency in a steady linear fashion we'd all be living in houses with 3' thick walls. With a forge you want to heat the insulation to keep the heat in where it is usable and safe but too much and you waste more energy heating the insulation than you save. You then also would have the problem of dissipating the residual heat after shut down.

Edited by Vern Wimmer
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