Cat litter forge help

[Cdworks]

How do I get this cat litter into a usable form?

[Dan C]

I gave up on cat litter and got refractory cement w some crushed firebrick

[Cdworks]

Dang. I know it works there's a hundred people that have used it and it worked... its just getting it into a usable state that is a pain

[Rich Hale]

Have you contacted any of those poeple?

[Dan C]

Yes I'd seen many online that said they used it. It just wasn't working for me at least. So i decided to quit messing with as I just wanted to get going. There was another thread out here about another alternative. Search refractory cement n u should find it.

My only experience with it was 2-3 days it still wasn't dried and what did dry cracked. As recommended I'd bought the cheapest I could find without any scent or perfume.

[Glenn]

Kitty Litter

The most common material is clay, although recycled paper "pellets" and silica-based "crystal" variants are also used. 

 

Additional research lists the material as Fullers Earth, granulated bentonite clay and others. Clumping litter usually also contains quartz or diatomaceous earth (sometimes called diatomaceous silica), Biodegradable litters are made from various plant resources, including pine wood pellets, recycled newspaper, clumping sawdust, Brazilian cassava, barley, okara and dried orange peel. Silica gel litter, often referred to as "crystal litter", is a porous granular form of silicon dioxide, Manufactures add things such as baking soda for odor control, fragrances, and many other ingredients.

 

Check the bag of kitty litter you purchased to find the ingredients and the name and address of the manufacture. Then contact the manufacture if you have additional questions about the contents of their product. 

 

The point is you may not be using the same kitty litter mix as the next fellow is using. 

 

When you buy or build a forge, there are products specifically designed for that application. Much research and development and testing was done before the product was made available to industry and maybe the public, Look into those products for your application as they work, you can contact the company if you have problems and the company will (or should) assist you with your specific application. They want you to use THEIR product, and want you to be happy with its performance so you will tell others.  

[Dodge]

I read something a while back that it needs to be "cheap" litter. The cheaper, the better. It has less additives. The better cat litters are better FOR cat litter and not refractory because of the additives. IIRC, polymers are added to the better litters to keep them in granular form but still absorb urine readily. This makes is a poor candidate for hydrating unless it is pulverized into a powder. Cheaper litter doesn't contain the polymers so they absorb water easily and can be turned into "clay" with less labor involved.

[SnailForge]

How do I get this cat litter into a usable form?

 

First, use the cheapest possible. That will have the least additives.

Then, just add ashes, some cement, and straw.mix it thoroughly, and only then add water. Lots of water. The kitty litter will absorb a lot.

Continue stirring and adding water until you have a thick gooey paste. That is when it is ready for use.

[Cdworks]

the only ingredient is "ground clay" its the brand that was recommended on here. Thanks for the info. I let the litter soak over night to dissolve the pellets. All i have to add to it is Sand and ash. I'll see what it does. Thanks again!

[Neil Blythin]

For best results, the clay pellets should be ground or pulverized into a clay powder, then hydrated. Add the water a bit at a time. Too much and its a horrible, nasty, sticky, gooey mess.

 

I helped a couple of guys to do this before. The first guy just added water to the kitty litter, as-is, and it was a disaster. The second guy ground the pellets up first, and it was far less of a disaster.  But in either case, I'll never help out with doing this again.  I don't think either turned out that great in the end.  Sure, it's cheap. And it does insulate well enough. It's just not a very elegant solution.

[Frosty]

Bentonite clay and sharp silica sand. Depending on the ratio of clay to sand it's used as green sand for casting up to iron casting, lining and repairing cupola iron melters, and various and sundry furnaces, including forges.

 

Here again we get into the, anything can be MADE to work category of things. sure it CAN be done but is it worth it? It's hard to beat for lining a cupola, green sand casting and making the plug in the cupola but as a gas forge liner? There are better alternatives, fire clay and sand being high on the list of backyard refractory mixes.

 

You'll run into some of the same characteristics no matter what kind of clay you use. Clay is hydrophilic meaning it LIKES water and will distribute any moisture equally throughout the entire mass. It just takes time. The PITA part of this is how little free flow water enjoys in clays. Yeah, want your pond to hold water? Clay it. It takes tempering to get the moisture evenly distributed. I like wetting the sand before mixing it in. Then mix the dickens out of it and then seal it in an airtight container and just let it set for a day or so. If you have to adjust the moisture content add just a little water or dry mix at a time and let it temper over night. If you try rushing it, you'll mix till your arms feel like falling off and it still wont be even and you won't know till a day or so later.

 

Mixing clay can be a real pain. When I'm making a refractory liner I use fire clay, sand and add saw dust if I want insulating "light" brick. I like ramming it just damp enough to clump if squeezed hard in your hand. It should break cleanly without crumbling or leaving damp clay on your hands. for the fire chamber liner I ram an inch of mix without sawdust and fil the rest of the form with light mix.

 

It ain't perfect but it's okay. Commercial fire brick works better but is WAY more expensive, a 25lb. sack of fire clay costs less than 4-5 fire bricks.

 

Frosty The Lucky.

[Cdworks]

thanks All! I used just the clay so when that disintegrates I will add sand to the mix. I appreciate all the information I had to let the kitty litter soak for about a day to get it into a usable state. I have batch number two soaking and will probably add some sand to it this time. After I get the fire pot built up I have to add a table to my construct and then have to crush my coal. Most of my coal is golf ball size plus :/

[Dan C]

This all explains at least why it didn't work for me.  I only mixed it with water and didn't grind it up beforehand.

[Nobody Special]

I used to use sodium bentonite cat litter in a casting furnace using the backyardmetalcasters.com recipe with portland cement, sand and perlite.

 

(yes, I know the portland slags in a furnace at much above brass melting temps, or in a gas forge when it gets crazy hot, but I've forged with this mix on a coal forge and it works well with patching once in a blue moon.)

 

For about the same price though, you can get a 50 lb bag of fireclay at a masonry store (I know there's one in huntsville that sells it at $7 a bag.) or if you have to have bentonite, it's sometimes sold at feed stores as a clay pond liner, and....it's not pelletized and baked like cat litter. 

 

(dunno current price, last time was about 10 yrs ago at 4 bucks a 50 lb bag in texas, dcraven it's easy to get in texas cheap because it's mined in west texas.) 

 

Also, I've found it makes a pretty crumbly refractory no matter what the mix, but the dryer the better when mixing it and ramming it. Adding too much water is always a bad temptation because it makes it easier to mix. Also, ram thoroughly, let it dry well for a few days and warm SLOWLY the first time, as trapped air or steam explosions blowing out chunks of refractory shrapnel are scary and can tend to hurt. Not that I did that the second time I built a casting furnace or anything (too much water, fired too soon/fast)......and good luck!

[Cdworks]

Thanks I will check with the local supply stores for bentonite clay next time around. thank you!

[Cdworks]

So I got the kitty litter to work. I pulverized it and it was a lot easier than I thought. I found a unique tool. I happened to have an extra coffee grinder that worked perfectly for pulverizing the clay. I mixed it with portland cement and sand and built up my forge. It has cured for over a week. Do i still need to light a small wood fire to draw out any moisture before running it full blast?

 

Here it is!

 

https://www.dropbox.com/sc/4q6atm8zdc7dsku/gOF6n1ECfl

[Charles R. Stevens]

Bentonite expands when wet. All clay dose to an extent but that's what bentonite is known for, so when it dries it will have big cracks.
Might have better luck with fire clay sand is ok as grog but ground up fire brick, or old flower pots works better.
If your looking to home brew might try this link, some one else posted it on an earleyer thread.
http://ezinearticles.com/?Depression-Refractory-Mix-For-The-Backyard-Foundry.&id=85797

[Bentiron1946]

My first melting furnace back in 1969 was made from the cheapest cat litter there was at the time, straight Bentonite clay, I think it was a $1.25 for a 25# bag. I mixed it up in a couple of 5 gallon buckets with mason's sand and let it set for a week and then rolled it into balls and rammed them into another 5 gallon bucket with a sheet metal form in it. I let this set for a week then built a wood fire in let it cook slowly, then patched the cracks with more clay/sand mix, let it set and then fired it off with my burner and melted 5 pounds of brass, success, I had my first pour! My next melting furnace was made from an old gas fired water heater tank and I lined it with standard fire brick held in place with Bentonite clay, yes, it works for a mortar too, then I made a wash out of it and painted the inside of the furnace with it and made a rammed lid of clay and sand.

[SierraBladeAndTool]

I have my Hibachi forge currently curing.  
I did a test mix a few days ago: 1-1-1-1 of fine screened concrete/ wood ash/ sand/ cat litter >>>>  It was UGLY!  Gobbed and cracked up... no.

So... I bought two little containers of Furnace Cement... made another better batch of clay from ash/sand/litter (no cement this time).     I lined the metal base and sides with 1" or so clay mix... set in my air pipe, then edge mortared my fire brick with the proper furnace cement... and set into place.

  

Packed it all in hard... pressed into all gaps... and then seam sealed on the fireside with the furnace cement.   Going to leave to cure a few days... and any drying cracks I guess I can just make a slip like paste and fill and smooth over right?

I'll start a thread on it with pics soon... (figured it out... some pics below)

The "burn" was to make my wood ash... and the coffee can is holding my SCREENED combo of litter/sand/ash (50/20/30%s)

 

 

[Arbalist]

I can't remember the exact mix but it was cat litter (bentonite) Portland cement and Perlite. Cheap and easy enough to mix and shape.



It's easy to get hung up about what other folks use but we don't all have easy access to the best materials or have to work on a tight budget.

[Logan Bryant]

So does this kitty litter clay harden up hard enough to make its own firepot?

[ThomasPowers]

Take a shovel.

Dig a good scoop out of the yard;

you now have a forge---Start using it instead of worrying about if it's hard enough or soft enough.  The forge pot is just to keep the fuel together for the tuyere's access;  it doesn't need to be all that hard  As I've mentioned I commonly use old adobe brick "mud" to build firepots when I do viking era Demos.

[Charles R. Stevens]

Sand and ash and a sprinkle of water are hard enugh, and the reason I recomend a brick or two as a floor is only to keep us from getting to close to the wooden floor when we clean out the forge and rebuild the fire bowl. The only reason I used clay is that's what was under my feet. You don't need a special mix, 

[Kozzy]

Pondering this from a concrete perspective--the strength in concrete comes from the aggregate filler.  You also don't want too much cement to filler because that's the weak part and shrinks.  Think of the cement as glue and the sand and aggregate as the structure being glued together:  What if you tried that with 95% glue and 5% material being glued?  Clearly that'd be a big messy failure.  Yes, I know we're talking clay and not cement as the binder.

Obviously a forge wouldn't use aggregate in the normal sense and would lean toward sharp sand or some other fillers instead within the clay "glue". 

No, I haven't experimented with this directly for the perfect mix--just trying to steer the thought process toward a similar subject on which there is a TON of research and information to draw from.  Typically it seems that mortars are strongest with 2 to 3 parts sand to 1 cement....and I bet clay mixes follow a similar trend.

[JHCC]

Looking back at the OP, I realize that everyone here has made a horrible mistake of understanding. Let's go back to the beginning, shall we?

On 7/6/2013 at 7:37 PM, Cdworks said:

How do I get this cat litter into a usable form?

Put it in the litterbox, and send in the cat.