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Jeff Wright 07-05-2018 10:56 AM

Question: Yield from Spruce Pine batch
Hi all. I have a quick quick question that I should know the answer to but all my notes are packed away. If I melt 50 pounds of Spruce Pine batch, how much glass should I expect the yield to be?

Oops - sorry for the typo in the question. Seems like I can't edit it.

Pete VanderLaan 07-05-2018 12:50 PM

I don't have the exact number in my head but it was between 16-19%

Jeff Wright 07-05-2018 03:04 PM

Thanks Pete. I'm assuming that is the loss factor. If it's the actual yield then I have to rethink what I'm doing!

Pete VanderLaan 07-05-2018 04:35 PM

think this way: for every hundred pounds you melt, you get 81 lbs of glass. This is a valid argument that cullet sellers make that's real and true. in cullet, 100lbs is indeed 100 lbs. SP is higher in volition loss than some , lower than some others. It's all in the Carbon dioxide loss.
In favor of batch, the working range is longer, even if it's the same formula. The brilliance is better and it's normally less cordy. Working range is way better. How did I used to put it?

"Oh, no free lunch " That was it...

In Game of Thrones? "Counting Coppers. " Make better work.

Jordan Kube 07-05-2018 04:55 PM

My spreadsheet has the glasses I melt that are similar to your formulas, Pete, coming in at about 15% calculated.

Pete VanderLaan 07-05-2018 05:16 PM

I can believe that Jordan.

Co2 is clearly an influence. Batch as opposed to cullet is still a better glass, but that has to matter.s f
I have questions for you when you used the lithopones for the cad sel colors. Could you PM me as to what you were doing? I'm quite interested, particularly given the way current events are leaning.

Josh Bernbaum 07-06-2018 09:00 AM

Moisture content has to be factored in with the pelletized batch, right? I imagine that is some weight loss there too, more so than in un-pelletized, powdered batch. When I have melted my own batch mixes, the level seems to drop down far less than the pelletized. Maybe partly due to less interstitial air spaces between the "pellets"?

Pete VanderLaan 07-06-2018 09:22 AM

There must be some Josh but not a lot. The chemically bound stuff is more what you need to look at. I don't see where SP uses any chemically bound water since it explodes like popcorn and that gets all over the place. I have been impressed at how easy it is to break up big iceberg sized chunks of batch in the mixer. It's an issue for me since I periodically now want to add colorants to the stuff Tom Mixes for me.
But if you add up all the CO2 that comes off the ingredients, you lose quite a bit. It's also true that home mixed, non pelletized batch melts a lot faster.

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