Kugler Colors in trouble

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Wrong group again?

(Rest Snipped for Brevity)

While your allegations are interesting, you provide no independent source for your comments. I suppose you could provide some documentation for this long rant, eh?

Actually, the real question is why this person thinks this is surprising and unknown. I have known that Kugler (and other) colors for glass contain lead, arsenic and cadmium since the day I started using them in my first glassblowing class over ten years ago. It has always been true that vessels to contain beverages or plates surfaces made of glass using these colors must be cased with lead free clear. Normally this is done by doing a gather of clear glass, picking up a chunk of color and blowing the clear through the color so there is a thin layer of clear on the inside. Many colors can only be made with cadmium (yellow) and lead in glass make the fit of different Coefficient of Expansions much easier.

All reds and yellows are lead free and always have been and most every glass regardless of where or who made has arsenic in it as a minute additive for fining as well as antimony for the same reason. Neither of which has ever been a problem except when those chemicals are handled in their raw state. Reds and Yellows have always been problematic when it comes to fitting a base glass because they do not contain lead. The problem for any glass including lead based glasses and enamels is their relative chemical durability. Chemical durability is in a nutshell the ratios of the alkali to silica. If those ratios are out of wack then you can get levels of solubility when the glass is exposed to the moisture in the air. The same holds true for lead leaching for the same reason. If the ratios are correct and the glass is tested for chemical durability then there is little to no problem. If and when Cadmium and or Selenium reach their vapor point you will not smell it, you will smell fluorine opals though. Been their! The gassing of fluorine opals when being melted in the furnace and worked in the glory hole is problematic as the fumes will turn to HF when they come in contact with the moisture in the atmosphere as well as your lungs. There is no problem for those of you fusing those type glasses as you are not at the vapor point of the fluorine. Oh yes, it is never a good idea to breath any vapors or dusts from anything found in the glass studio. 1200 C is 2192 F. Also, what's wrong with killing rats? Don't over react to the posting as the dangers from color rods, and frits are little to nil to none when handled correctly as in always pick up powders in a powder booth that has a good exhaust and wear an approved dust mask when using powders for projects. Having said all of the above I would say it is my understanding that all the rod companies are aware of the lead problems and have been working to get the lead out of their rods as the European lead laws have come into existence. The late great Klaus Kugler sold his company because he did not wish to reformulate all the glasses he had in his catalog. One of the problems with the rods is that fit for certain base glasses has now become problematic as they have removed the lead from their products. Read Mike Firth's posting as well. Why is this the wrong place for JoJo's posting? Seems to me to be the perfect place for it.

JoJo

Henry,

Date: Fri, 27 Aug 2004 18:35:58 +0200

From:"JoJo"

Organization: OSHAGERM

Newsgroups: rec.crafts.glass

sorry wrong group

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My comment was a dig at somebody feeling compelled to post a message titled "sorry" that said nothing more than "sorry wrong group". Strange post. Have you ever clicked on the wrong group when browsing newsgroups? I have, but it never occurred to me to let the group know of my error.