Do Wood Forges Need Firebricks?

[GeneralHatchet]

Hi, I've made a couple of knives via stock removal, and I want to try my hand at forging one.  I'm planning on building a wood forge using a gas grill lid.  I'm using wood because I have an unlimited, free supply of it, and coal is hard to get cheaply in my area.  I know that wood has a number of drawbacks, like it has to burn a while to get the coals burnt down to forge with, but I'm still going for it. 

My question is this, do I need to line the inside of the grill lid with firebricks?  I'm 90% sure the lid is stainless steel, and I'm using black iron pipe with holes drilled in it for the air supply.  Most of the coal forges I've seen don't have firebricks or insulation, but there's also usually a huge bed of coals which I'm assuming provides insulation.  Will the forge get hot enough without firebricks to forge with? Or will the stainless steel get too hot and deform causing the whole thing to fall apart?  I know Whitlox's wood forge uses kaowool and firebrick for insulation, which makes me wonder why wood needs insulation, but coal doesn't.

On a side note, I know coal forges need a hole in the bottom to push the burnt ashes through, should I cut a hole in the bottom beneath the air supply pipe for the wood ashes to fall through?

I'll probably have more questions coming.

Thanks for the help,

Luke

[JHCC]

Do a web search for "Tim Lively washtub forge" to get an idea of the kind of thing you're working towards. You need some kind of insulation under the fire to keep the forge shell from burning out.

Keep in mind that a wood-fired forge is not heating the metal with the wood flame; rather, you are combining a charcoal forge below with a wood fire on top. You'll need a forge that will hold a fire big enough to produce enough coals to heat your workpiece effectively. 

[Meadowgrove]

If you have an infinite supply of wood, it would be useful to build some kinda retort and make your own charcoal. Search the forum for further instructions. I think there was a pinned thread about it in the solid fuel forges section...

[GeneralHatchet]

Thanks for the info. The Tim Lively Washtub Forge is exactly what I was looking for.

I've thought about making the charcoal beforehand, and I might give it a shot, but I want to have a forge that I can throw raw wood in and let it burn down to charcoal if I can't get making charcoal down.

Thanks again!

 

[Charles R. Stevens]

A couple of inches or Adobe mud will keep you from burning yourself on the tin, brick is not nessisary. 

[JHCC]

 

I want to have a forge that I can throw raw wood in and let it burn down to charcoal if I can't get making charcoal down.

Another option (a very simple one) is simply to have a fire burning separately, and adding the coals from that to your forge as necessary.

[GeneralHatchet]

Simple and easy, I like it, I'll give it a shot.

 

A couple of inches or Adobe mud will keep you from burning yourself on the tin, brick is not nessisary. 

That is exactly what I was thinking after seeing Tim Lively's Washtub Forge.  After a bit of research, I've seem them made with Adobe mud, ashes/water mix, and plaster of paris and perlite.  I'll have to decide which to go with and go from there.

 

Thanks for the advice guys.  It's been a great help.

[Charles R. Stevens]

You only need 10-50% clay and 50-90% sand. 

[ThomasPowers]

I took some gravel screen and made a shovel out of it to transfer hot coals but not ash or very small pieces of charcoal.  I really like being able to forge without the smoke and fire of doing your coaling in the forge.

[Arthur210]

I'm suprised none of the regular mentioned it, but if you put your location in your profile you may be surprised to discover that other IFI members live in your area. They may be able to suggest places where you could get coal at a reasonable price or, barring that, how to find other local resources.