redbate

Do I NEED rigidizer for Kaowool?

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Hi another question regarding use of Kaowool, originally I was going to just coat the inside of the forge with satanite and call it good since I can't find ITC-100 here but I was wondering after some research and not being able to make up my mind about it thought to ask you guys. Do I NEED rigidizer for Kaowool? Especially for the burner port? Because I was thinking I would just apply thin coat of Satanite around the burner port and thicker coating else wheres in the forge. Would this work or would I need to buy some rigidizer? It's hard to find but not impossible here, I think but would rather use what I have on hand if I could. 

Also side note, for the pressure gauge on the forge, I have a regulator that says Gauge on the side with a brass filler nut in there would I just have to buy a LPG gauge and attach it there?

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I've never used rigidizer for my forges; so I wouldn't sweat it.

Also I assume that most gauges are off and learned to adjust my burners by sight and sound and *never* expect that someone else's gauge pressures are accurate.

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I used Mizzou and it was relatively inexpensive, easy to apply and cure, and has held up great. Once it gets hot, which takes about 10 minutes my forge runs at 5 psi and will get steel glowing in a short amount of time.

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If your finish coat is thin enough not to stand up on its own, then yes you do need rigidizer. If you want the wool to last as long as possible, then yes, you need rigidizer. Rigidizer is cheap; building a forge without employing it makes as much sense as allowing your car to run low on engine oi, just to save a hew bucks.

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15 hours ago, redbate said:

 It's hard to find but not impossible here

Are you searching for rigidiser already mixed up? If so do a search for fumed or colloidal silica and make your own - its cheaper too

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6 hours ago, RobbieG said:

Are you searching for rigidiser already mixed up? If so do a search for fumed or colloidal silica and make your own - its cheaper too

Like the stuff West Systems sells to make resin thicker? Do I just mix it with water and spray it on?

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Yes and Yes.

Caveats: there are hydrophobic and hydrophilic versions of fumed Silica. You need a hydrophilic type. I think Cab-O-Sil M5 is probably the most widely-recognized product.

When I last bought some of the commercial rigidizer, I measured it's density for when I got around to making a homebrew version. I got a density of 1109 grams/litre. I don't think it's critical at all, but it gives a starting point. 

At 1109 g/l, it suggests that there is a little over 100g of fumed silica per litre of water: about 2 Oz/pint. Checking out prices for the West System 406 over here, it looks like it would cost as much to homebrew using the West stuff as it would to buy the commercial rigidizer, so I'd suggest checking out generic fumed silica products. 

 

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2 hours ago, timgunn1962 said:

Yes and Yes.

Caveats: there are hydrophobic and hydrophilic versions of fumed Silica. You need a hydrophilic type. I think Cab-O-Sil M5 is probably the most widely-recognized product.

When I last bought some of the commercial rigidizer, I measured it's density for when I got around to making a homebrew version. I got a density of 1109 grams/litre. I don't think it's critical at all, but it gives a starting point. 

At 1109 g/l, it suggests that there is a little over 100g of fumed silica per litre of water: about 2 Oz/pint. Checking out prices for the West System 406 over here, it looks like it would cost as much to homebrew using the West stuff as it would to buy the commercial rigidizer, so I'd suggest checking out generic fumed silica products. 

 

Over here though West Systems 406 would cost me about 13 bucks + shipping where as commercial rigidizer which I had to go through a hoop and loop to get a contact that would sell it to me in litres would cost me about 35 bucks+ 20 bucks in freight.

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Fumed silica is used in many products; it has even been used as a thickening agent in shakes at the local drive-in (burger joint). If nothing else, follow the food additive angle to find some locally.

timgunn1962

Hydrophobic and hydrophilic versions of fumed Silica?  I didn't know that. Thank you.

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by the way, fumed silica is light as a feather, so if your shipping on it is more than minimal, then you are being ripped off--big time!

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On 4/6/2017 at 3:50 PM, redbate said:

Over here though West Systems 406 would cost me about 13 bucks + shipping where as commercial rigidizer which I had to go through a hoop and loop to get a contact that would sell it to me in litres would cost me about 35 bucks+ 20 bucks in freight.

That is the product I was considering, we have a local marine supply store which sells it, only a few $ for the small amount I need :D

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On 4/28/2017 at 2:18 AM, EnglishDave said:

That is the product I was considering, we have a local marine supply store which sells it, only a few $ for the small amount I need :D

Go for it mate, I just got one with building it and it seems to have served me very well I think.

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5 minutes ago, redbate said:

Go for it mate, I just got one with building it and it seems to have served me very well I think.

I actually went out this morning and got my Kaowool from a pottery supply house and then some West 406 from a marine supply store.

Have mixed up a batch and sprayed it on (with a nice blue food color mixed in so I can see where I have missed). No idea how it will dry/cure but we will see tomorrow :)That colloidal silica sure is some weird stuff, so light it blows away if you are not careful when you open the tube! Made sure to wear a face mask also, probably not the best stuff to breathe....

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1 minute ago, EnglishDave said:

I actually went out this morning and got my Kaowool from a pottery supply house and then some West 406 from a marine supply store.

Have mixed up a batch and sprayed it on (with a nice blue food color mixed in so I can see where I have missed). No idea how it will dry/cure but we will see tomorrow :)That colloidal silica sure is some weird stuff, so light it blows away if you are not careful when you open the tube! Made sure to wear a face mask also, probably not the best stuff to breathe....

Oh yeah I wasn't expecting it to make so much dust but I got lucky wearing my respirator for doing Kaowool related stuff. If you are curing the sillica or satanite or something similar, put the forge on it's end so the holes are perpendicular to the ground and hang a halogen light in it. I cured Satanite largely by just doing that. Good luck with everything mate!

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Just now, redbate said:

Oh yeah I wasn't expecting it to make so much dust but I got lucky wearing my respirator for doing Kaowool related stuff. If you are curing the sillica or satanite or something similar, put the forge on it's end so the holes are perpendicular to the ground and hang a halogen light in it. I cured Satanite largely by just doing that. Good luck with everything mate!

Thanks, will let you know on here what happens!

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Did you cut your Kaowool a LITTLE long so compression holds it after you press it in?

Frosty The Lucky.

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1 hour ago, Frosty said:

Did you cut your Kaowool a LITTLE long so compression holds it after you press it in?

Frosty The Lucky.

Yes indeed I did, to be honest I was pleasantly surprised how stiff the blanket was, it is nice 1" thick stuff and does a pretty good job of holding itself in shape. I did the silica rigidizer thing anyway since I had bought a tub (only $13) and will apply a thin metrikote layer once that is cured. 

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Good, it doesn't stay so stiff when it gets HOT. Rigidizer makes a huge difference and Metrikote is a little armor for the cause.

Frosty The Lucky.

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On 4/6/2017 at 3:00 PM, timgunn1962 said:

I got a density of 1109 grams/litre. I don't think it's critical at all, but it gives a starting point. 

At 1109 g/l, it suggests that there is a little over 100g of fumed silica per litre of water: about 2 Oz/pint. Checking out prices for the West System 406 over here, it looks like it would cost as much to homebrew using the West stuff as it would to buy the commercial rigidizer, so I'd suggest checking out generic fumed silica products. 

 

That's a little higher than I expected it to be.  What did you use to test the density?

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More than you probably ever wanted to know about Silica .

It appears that while diatomaceous earth is also amorphous like fumed silica, the particle size is much larger in the micormeters vs nanometers of fumed silica.  That would be to easy if we could just buy some diatomaceous roach powder at a big box store. 

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I poured 1 litre of Rigidizer into a measuring jug, stuck it on the kitchen scales, noted the weight, poured out the rigidizer, weighed the measuring jug again and subtracted the weight of the jug.

I like simple and low-tech, it minimizes my chances of screwing up.

2 hours ago, ede said:

That's a little higher than I expected it to be.  What did you use to test the density?

 

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9 hours ago, Frosty said:

Good, it doesn't stay so stiff when it gets HOT. Rigidizer makes a huge difference and Metrikote is a little armor for the cause.

Frosty The Lucky.

So tell me if I have misunderstood please but the rigidizer only becomes rigid once fired, is that correct?

Is it OK to apply more layers over the top of each other if the first one is not stiff enough?

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I am at the stage right before EnglishDave.

I am searching for the right rigidizer product to purchase.

So, I just search for any "fumed silica"? 

Is this what you bought @EnglishDave [link to commercial site selling West System colloidal silica removed]

Edited by Mod34
Link to commercial site removed per TOS

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