spruce pine gaffer batch

[Drew Hine]

Hello, I came across a pallet of spruce pine batch gaffer formula from a glass caster going out of business. I have been melting it for the last month with no issues. I was making production pieces today and realized how soft the glass is. It just does not set up on the pipe quick enough to keep up with the pace of what we are making
My question is can I add anything to the batch to stiffen it up? I was thinking alumina hydrate? Any help would be appreciated.
Thanks

[Pete VanderLaan]

SP claimed to me that they only sold two tons of the Gaffer batch, the same amount they said they had sold of mine. I think that is just bad record keeping.

To change the batch will change the expansion. To stiffen it will take the expansion down a good deal. Are you aware of that? Currently, it was calc'd as a 96, making it compatible with all gaffer color although there seem to be going issues with copper blue opals and greens, not surprising.

So if you don't think changing the expansion will pose a problem for you, simply adding silica will take it down. It must be remixed. You may regret what you get. Silica is quite powerful moving expansion.

[Eben Horton]

Compressed air is your friend

[Andrew Horch]

Maybe find someone who wants a very soft glass and trade with them.

[Pete VanderLaan]

I would just set it aside for the right occasion

[Art Freas]

Originally Posted by Eben Horton

Compressed air is your friend

Big thumbs up to that. When we used System 96 Studio original we didn't use air at all because the last thing you wanted to shorten the working time. Sys 96 was tough if you needed long working time. Now that we are using Bomma we definitely use air when doing production. Production can definitely make you want shorter working time with some products, one of the reasons we never made the switch to Spruce.

[Brian Wong Shui]

Originally Posted by Pete VanderLaan

SP claimed to me that they only sold two tons of the Gaffer batch, the same amount they said they had sold of mine. I think that is just bad record keeping.....

Over what time period was this claim made? When our studio was operational, we went through 4-6 tons/year of Gaffer from Spruce Pine.

[Pete VanderLaan]

According to Greg about four months back, he claimed that SP only sold two tons of Gaffer, the same amount that they sold of mine or so he said. He did not specify any time period. Spruce Pine is hard to believe on this point.