WarmGlass.com

Oh so close!!! I thought we'd have agreement and nothing else........ Maybe next time.

I find it really interesting how some people here get totally worked up about a small amount of glass dust, while in industry there is a crazy amount of glass dust in glass factories EVERYWHERE. An awful lot of these shops are scrutinized heavily by OSHA and other government boards yet no one has a problem with it. Try going into a granite counter top manufacturer there is a good chance you can't see the far side of the shop through the haze (slight exaggeration)

(FACT) glass dust DOES NOT give you silicosis, There is a huge difference between amorphous silica and crystaline silica. Crystaline is harmful and amorphous is considered a nuisance. The silica in glass is crystaline until it's been melted into a glass, that process makes it amorphous. That doesn't mean it's good to breath huge amounts of it in however. You are literally breathing deadly gases and fumes right now, you are not dropping like flies.

It's the dose that makes the poison.

Fun fact the most paranoid person I know regarding glass dust smokes 2 packs a day and drinks like a fish. Go figure

For those who think I am blowing "silica"

This is from Greg Rawls website, he's a member here and a CERTIFIED INDUSTRIAL HYGIENIST

http://www.gregorieglass.com/Health_Saf ... mical.html

Ground Glass

OSHA classifies glass dust as a “Nuisance Dust”
Ground glass does not cause silicosis.
You can wear a respirator if you are concerned about exposure.
Glass is made from sand, which contains silica - a naturally occurring mineral silicon dioxide (SiO2).
Crystalline forms of silica, also known as “free” silica, can contribute to the development of silicosis under prolonged exposure conditions.
It is important to understand the difference between glass and crystalline silica because exposure outcomes are extremely different!
Glass is a silicate containing various other ingredients which have been melted and upon cooling form an amorphous, or non-crystalline structure.
While silica (SiO2) is a primary ingredient in the manufacturing of glass, when glass is formed under heat, the crystalline structure is changed to an amorphous structure and is no longer considered crystalline.
Ground glass is rarely respirable because the particle is too big.
Always use wet methods when grinding glass! Water captures the dust.
Sometime other chemicals are used to add color to glass such as arsenic, lead, cadmium. These are usually present in low concentrations and are bound to the glass and not readily available but could present an exposure issue under some circumstances!

Nuisance dusts are still a pain in the neck to breathe and if you're power-grinding any more than a simple edge touch-up, there's enough glass dust kicking around to cause other problems. Ground glass is abrasive, and if it starts floating around it will travel with you to your studio, your living spaces, car, etc. It gets into equipment (I ruined a perfectly good chopsaw motor that way), it's a slip hazard, it makes for very gritty sandwiches, it can contaminate frit or, if you grind near your kilns as I do, float into the elements, shelves, layups, etc. And the more the dust flies, the more likely you are to kick it up again when you clean...and start the whole problem all over again.

I think those are all good reasons to use water with any significant power grinding. I also think that you're less likely to clog your abrasive belt/disc/etc. if you've got a constant stream of running water clearing it out.

And while I agree that you can still overheat and break glass under a water stream, you're far more likely to do it when grinding dry. Forcing the grind is often a problem with hobbyists--flooding the area with water gives you a bigger margin for error.

No disagreement from me here, I have 7 motorized pieces of coldworking all use water except one. (not counting handpads etc) The one that doesn't use water is hardly ever used except to arris a large piece of glass.

Some of you just don't get it. Every single piece of glass I cut gets it's sharp edges ground with my belt sander. If it is a small piece, I use the diamond hand pad. I work with float glass between 5mm and 10mm, mostly 10mm. The dust created is indiscernible. I do this for 2 reasons. First it heals microstarts so that glass does not run when heated in the kiln. I learned this from the tempering industry. They undoubtedly learned that glass with raw sharp edges breaks more when heated up than glass that has seamed edges. The other reason I do this is to significantly reduce finger cuts while cleaning or handling the glass.

A few times a a year I want to grind the whole edge of a 6mm light fixture or a 10mm bowl. . Yes if you dwell in a spot you will heat it up red hot, and a divot falls out. If you move along and come back to an area that needs extra attention, it works fine. If I detect dust, I'll spray it with the glass cleaner. That keeps the dust down. It is just a different way of working.

Most people in the warm glass world work with wetbelt sanders. In the neighborhood glass shops people use both wet and dry. It depends both on what you have for equipment and what you want to do. There are enough people using dry belts so that companies bother to manufacture them. If it were one or 2, they would disappear.

The best tool to use starts with the one you have. For glass you can hold in your hand, the wetbelt sanders are great. I would not want a 4 x 106 dry belt. My 1.125 x 21 works wet or dry. Of all the dusty exposures I need to protect myself from, seaming edges is a negligible one. If it were true that I would surely break glass grinding an edge, I wouldn't do it that way.

All that said, I'd like to own a wet disc grinder for doing edges (not for seaming).

Ok, I think I understand that either way will work. It was just so much quicker to smooth the edges of a strip cut piece using the makita 5010 than the wet belt sander(if mine was working, that is!). But depending on the care you take either one will do the job.i think it is always nice to have a variety of methods to finish pieces. So by tryin them all we will know what works for our individual needs.
I am not afraid to try the makita now that I have had everyone's input. So I'll give it a whirl and see if it works for me. In the meantime I wll be calling Covington in regards to my wet belt sander. I just need to fin absolution to my problem...an affordable one . I love glass but I really don't generate an income!!

Thank you for your input and thoughts. I will share my results !
Susanne

Bert Weiss wrote:Some of you just don't get it. Every single piece of glass I cut gets it's sharp edges ground with my belt sander. If it is a small piece, I use the diamond hand pad. I work with float glass between 5mm and 10mm, mostly 10mm. The dust created is indiscernible. I do this for 2 reasons. First it heals microstarts so that glass does not run when heated in the kiln. I learned this from the tempering industry. They undoubtedly learned that glass with raw sharp edges breaks more when heated up than glass that has seamed edges. The other reason I do this is to significantly reduce finger cuts while cleaning or handling the glass.

A few times a a year I want to grind the whole edge of a 6mm light fixture or a 10mm bowl. . Yes if you dwell in a spot you will heat it up red hot, and a divot falls out. If you move along and come back to an area that needs extra attention, it works fine. If I detect dust, I'll spray it with the glass cleaner. That keeps the dust down. It is just a different way of working.

Most people in the warm glass world work with wetbelt sanders. In the neighborhood glass shops people use both wet and dry. It depends both on what you have for equipment and what you want to do. There are enough people using dry belts so that companies bother to manufacture them. If it were one or 2, they would disappear.

The best tool to use starts with the one you have. For glass you can hold in your hand, the wetbelt sanders are great. I would not want a 4 x 106 dry belt. My 1.125 x 21 works wet or dry. Of all the dusty exposures I need to protect myself from, seaming edges is a negligible one. If it were true that I would surely break glass grinding an edge, I wouldn't do it that way.

All that said, I'd like to own a wet disc grinder for doing edges (not for seaming).

I certainly agree with your first statement, Bert. We've already said that if you dwell in a spot on the glass you will heat it to red hot and a divot falls out. The point I think you're missing is that learning not to "dwell" can take a lot of practice--not everyone asking questions about grinding will have that much practice. Nor will they be experienced at polishing with a dry grinder, which was the other part of her question.

There's a difference between grinding a whole strip-cut blank to shape and seaming the sharp edge of a piece of float. Seaming float doesn't remove much material, so there's less dust. (You may want to check your discern-o-meter; I can generate a "discernible" amount of dust when I run a diamond pad down a piece of float, let alone when I dry-sand it.) For those of you who might not know what "seaming" is, here's a video of it, done with a dry sander:
http://www.dailymotion.com/video/xbzr0a ... _lifestyle
Notice the fellow wiping away that indiscernible amount of dust from the mirror as he works. That's the stuff that floats all over your studio.

Strip-cut blanks typically require far more material removal...and create commensurately more dust.

I'm just tickled to death that people with their own commercial glass shops can grind down miles and miles of glass with a dry grinder. If I'm going to dry-grind, I'll do it outside, for the afore-mentioned reasons.

So, the better answer is "it depends on what you're working on, how much glass you need to remove, whether your studio can stand the dust, and how practiced you are at grinding and polishing wet."

Why take advice from someone who has broken glass by overheating it on a wheel with a water feed?
That implies a staggering level of bad technique and incompetence.

Brock wrote:Why take advice from someone who has broken glass by overheating it on a wheel with a water feed?
That implies a staggering level of bad technique and incompetence.

I did it in the cold shop at Pilchuck. Isn't that what school is for? I think I overheated it using Cerium. If you never find the edges of what works and what doesn't you learned little.

Ah, now I get it. You learned to ignore instructions . . .