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Sodium silicate


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I'm building a forge out of a oxygen cylinder. I have all the materials to build it but a adhesive to hold the Kaowool in. I'm using 1" blankets that will result in 2" of insulation. I wand to bond the wool to the inside of the forge and then bond the second layer to the first. I'm aware I'm supposed to use sodium silicate but not sure we're to get it locally or the right mixture that's required. Thanks

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My blanket was dense enough to be held up by compression alone. I only rigidized (e.g. the inside of the chamber and the but sticking out up front) the exposed parts, no glueing needed. I Just rolled up the blanket tight enough to slide in the cylinder and then unrolled it. Repeated that for the second layer.

Out of curiosity: What density blanket are you using? Will your forge be open on both sides? If the end will be closed cut out 2 layers for the back first and place them before inserting the rolled up blanket.

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I'm using one inch blanket but I'm not sure of the density because it was given to me. My forge will have hard brick doors at both ends. 

 

I have a rigidizer and then it will be coated with satanite then itc 100. I was hoping to get away with not having to use the silicate as adhesive.

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Sodium silicate isn't an adhesive in this use it's a rigidizer. You don't want the two layers of ceramic blanket bonded or you have to tear it all out to reline the forge. The refractory liner is a wear item, especially the fire contact and floor, building the forge so the inner liner is easy to replace is a good thing.

An oxy cylinder is an awfully heavy forge shell but using what you have on hand is a long standing blacksmith tradition. The bottom of oxy cylinders make excellent bottom dies for bowls, spoons and sinking for making hollow forms.

Frosty The Lucky.

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2 hours ago, Frosty said:

That explains a lot. No comment on Dave H. designs.

Frosty The Lucky.

I'm using what I had laying around is why I'm going off the super c design. Feels good to be able to utilize "junk" that my wife hates laying around. I'm glad to asked before buying stuff I don't need. 

Thanks for the tip on the bottom cylinder. 

Wouldyou think if I made my forge a little longer than 8" I could still get away with one 3/4" burner? It's 8" in diameter.

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Sodium Silicate comes in various densities. I think the units normally quoted are degrees Twaddle and my supplier sells both 140 and 75 and other sources may be different again. It means that it's difficult to come up with a simple dilution ratio in the form X Sodium Silicate to Y water.

I have found that diluting with tapwater to give a solution density of between 1100 and 1150 grams/litre gives a rigidizing solution that seems to work about the same as the commercial colloidal silica rigidizer in a forge application: I think it works out to around 17 1/2 to 18 1/2 Ounces per US Pint, but I'm not really familiar with the US units.

 

 

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1 hour ago, timgunn1962 said:

Sodium Silicate comes in various densities. I think the units normally quoted are degrees Twaddle and my supplier sells both 140 and 75 and other sources may be different again. It means that it's difficult to come up with a simple dilution ratio in the form X Sodium Silicate to Y water.

I have found that diluting with tapwater to give a solution density of between 1100 and 1150 grams/litre gives a rigidizing solution that seems to work about the same as the commercial colloidal silica rigidizer in a forge application: I think it works out to around 17 1/2 to 18 1/2 Ounces per US Pint, but I'm not really familiar with the US units.

 

 

Thank you for the info. I have a pint of a rigidizer I got from a foundry supply company. I'm guessing it's mixed at the right ratio. I all new to this but I'm starting to understand what it all does.

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Dave tends to really over rely on sodium silicate in his forge liner. Cementing the two layers of ceramic blanket into one solid mass defeats the purpose for using two layers using one layer of 2" would be just as hard to rebuild. Sodium silicate is also susceptible to being dissolved by hot flux and that's what he's using to bind the zirconium in flame contact.

While the forge itself may be fine I don't think much of his liners at all.

Frosty The Lucky.

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On 6/5/2016 at 9:53 AM, Firemn260 said:

sodium silicate but not sure we're to get it locally

One place to get it is at the auto parts store,  Look at the labels on the various snake oil radiator stop leak products, read the fine print and you will find it.

Bob

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