Using spectrum cullet for pate de verre

[Terry Gallentine]

I recently got a frit crusher and I will be using it initially to crush a large supply of system 96 scrap to use for pate de verre work. When I run out of clear scrap, I was considering crushing system 96 cullet. Will the crushed system 96 cullet be compatible with the crushed system 96 sheet glass? Is there a difference in 96 cullets and which would be the best for my purpose?

[Brad Walker]

Yes, they will be compatible.

Spectrum 96 cullet is made from trimmed off edges of regular System 96 sheet glass, so it should always be compatible with regular System 96 scrap.

[Terry Gallentine]

Thanks Brad. I know that I will be getting a little iron in the frit when I crush it but I read where a 10% solution of sulfuric acid will clean it out. I have easier access to hydrochloric acid and I was wondering if it would work as well as the sulfuric?

[Stephen Richard]

A superficial search of Google indicates hydrochloride will not do the same as sulphur

[Terry Gallentine]

I know that hydrochloric acid is used as a pickling solution for steel to dissolve scale so my thoughts are that it might work on the small amounts of iron that might be present in the crushed frit.

[jim simmons]

Use a STRONG magnet.
Jim :>)

I know that hydrochloric acid is used as a pickling solution for steel to dissolve scale so my thoughts are that it might work on the small amounts of iron that might be present in the crushed frit.

[charlie]

and put the magnet in a plastic bag first.

[Bert Weiss]

and put the magnet in a plastic bag first.

Good one Charlie!

[Morganica]

So is the idea that you wash the frit with dilute sulfuric acid to create iron sulfate or hydrochloric acid to make iron chloride, and then (since both are water soluble) you wash the frit again like crazy to dilute and remove the aqueous salt solution? You would want to make sure you get the frit very, very clean because I think both those substances will stain glass. Haven't tested, so don't know for sure.

Seems like the magnet would be a lot easier. BTW, of the two, the iron chloride is probably the nastier chemical to deal with. You're not dealing with a great deal of either, but I'd be careful.

[Terry Gallentine]

I ran onto the information about the acid wash in a dissertation from the Rochester Institute of Technology. The idea is to wash the frit with the dilute acid and then do a few rinses before neutralizing it with a base wash (baking soda solution). I have worked with metal salt solutions before and I have some experience with how they work with glass, so that doesn't bother me (at least not in the extremely dilute form that we are talking about). It just seems to be a good way to not only get the iron out but also any other organic contaminants.

[Tony Smith]

I can see how an acid wash might work with clear, borosilicate glass, but I would think the sulfuric acid would also react with iron or copper in the base glass, possibly striking the surface to a different color.

Tony

[Terry Gallentine]

Thanks Tony. I hope it won't have an effect on the glass but that will probably vary with the composition of the glass. As in most things, only trying it out will tell. I certainly don't want to change the makeup of the glass (not if I want to maintain compatibility).

[Jerrwel]

Thanks Brad. I know that I will be getting a little iron in the frit when I crush it but I read where a 10% solution of sulfuric acid will clean it out. I have easier access to hydrochloric acid and I was wondering if it would work as well as the sulfuric?

I'm as cheap as they come and want to recycle my scrap glass and I'm not terribly familiar with what size frit is used to make pate-de-verre, but I'm wondering if the iron bits might be small enough to sort out of the frit produced as powder. If so, can the powder just not be included in the frit to be used?

[Stephen Richard]

I have never been able to clean my home made powder or fine frit suitably to avoid discolouration

[Kevin Midgley]

Crush inside a polyethylene bag. Poly floats in water.

[Jordan Kube]

Forget about all that chemical stuff. Make yourself a ball mill. I welded up a frame that holds a 5 gallon bucket and then welded that to an old home depot cement mixer like this one: http://www.homedepot.com/p/Proforce-1-2 ... 5yc1vZc7qb

I found one for cheap on craigslist, already has a nice gear motor. Throw in some alumina balls and let it run for a day or two. You can get the alumina from United Nuclear but they're out of the 1.2" and 3/4" right now. This works in a small tumbler too if you don't need so much powder or you don't have the space.

[Terry Gallentine]

I do use a ball mill but only after I have used the frit crusher to take it down to a coarse or medium size. The ball mill works well for reducing the frit to a fine frit.

[Karen Ehart]

I have been using a ball mill to crush frit and really like it. The porcelain jugs are cracking and I would love to use an alternative. The cement mixer sounds like a great idea. I am not clear about how you use it. Do you put the glass and balls in the mixer without any kind of liner? Why did you weld a bucket bracket to the mixer? Thanks!!!!!

[Jordan Kube]

I'll try to get a picture in the next few days. I initially welded a bucket holder right to the drum. The 5 gallon bucket fits right in the mouth.

I did this for several reasons:
Easy to change and keep colors separate.
Easier to keep the dust contained.
The mixing barrel is just too big.

I eventually took the drum off and hacked something together that I just welded straight to the shaft.

[Terry Gallentine]

Jordan,

I like the idea of using a plastic bucket for a ball mill jar but I was just wondering how the bucket holds up to the milling. Is there much plastic abraded into what you are milling?

Thanks