8 replies to this topic

[defective]

i have found a few places that sell bentonite (sodium bentonite) and was wondering if this is the same stuff thats used in pyro. i havent bothered looking into it so i thought id try here first (cos im a lazy ba****d).

i have found 100g of it from youngs used for the clearing of liquids after or before fermentation, was just wondering if this is the same as that used in pyro.

any info would be great, thanks.

[pyromaniac303]

Yes, the bentonite sold for home brew beer/wine is the same stuff used to create clay plugs, but at £1+ for only 100g you are paying over 25 times the normal sale price!

Many brands of cat litter are pure, or almost pure bentonite, so you can either use these, or buy it from potters suppliers in pre-powdered form. Look for the cat litters with a relatively light colour, that say they are clumping. 5kg bags can be picked up for under £2 in the right places, but from that state it must be powdered with a coffee grinder or similar.

[defective]

Yes, the bentonite sold for home brew beer/wine is the same stuff used to create clay plugs, but at £1+ for only 100g you are paying over 25 times the normal sale price!

Many brands of cat litter are pure, or almost pure bentonite, so you can either use these, or buy it from potters suppliers in pre-powdered form. Look for the cat litters with a relatively light colour, that say they are clumping. 5kg bags can be picked up for under £2 in the right places, but from that state it must be powdered with a coffee grinder or similar.

i bought some cat litter actually to try it but i havent yet made a mill for any lumpy suff.

how about an old blender?

[mike_au]

In my experience milling bentonite just results in bentonite coated milling media. It is a horrible mess and rather annoying to clean up.

I think a blender would be a much better idea.

[seymour]

Be very careful with milling your cat litter. Not because it is dangerous, but because in many cases it is best to use it without any further processing. Yes, just those quarter inch grains.

They do indeed compact down perfectly well as is, and the corners bite in to the tube, reducing the chances of a blow out. Of course you will get a prettier plug using fine stuff, but you may have to compensate by adding an abrasive to make it work.

I advise saving yourself time and leaving the stuff as is.

[mike_au]

Agreed, the exception to the rule is if you are making small rockets where large grains won't fit around the tooling properly or are drilling your nozzles.

Admittedly a very good argument could be made that drilling nozzles is a bad idea.

Bottle rockets however are a really good idea

[seymour]

I always drill my nozzles, and have no problems.

Admittedly a very good argument could be made that drilling nozzles is a bad idea.

Yes, it is best to do it by hand, if at all. While I would not advise it, it is quite a common practice, even in commercial set ups!

[defective]

hi all, i went to my local wilkinsons store today and got myself probably a 10 or fifteen kilo bag of bentonite for 2 quid as cat litter.

i used my liquidiser on it and it turned out lovely not to fine but course enough to grip the walls of a tube.

[mike_au]

I always drill my nozzles, and have no problems.

Really? I've drilled a few and for the most part they held, but they tended to crumble a fair bit for the first few mm. I always made my nozzles a fair bit thicker than they really needed to be to cancel it out. Using finer clay works much nicer.

Maybe the best solution is a combination, a layer of fine stuff so the drill gets a smooth start and then a few layers of coarser grains to make the bulk of the nozzle. I might give that a shot next time I'm making one.