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-   -   homemade unoxidized batch suggestions? (http://talk.craftweb.com/showthread.php?t=12463)

Paul Stout 11-06-2019 11:16 AM

homemade unoxidized batch suggestions?
 
I'm interested in making an unoxidised batch, a 96, that has potassium, for melting sulfur/molybdenum ambers. Ive tried with our batch, East Bay regular, but the color doesn't take, I think because of the oxidizers. I know that SP sells a color base, and Im sure Jim would mix something for me but Id like to try myself.
I was going to start with Pete V's recipe of:
63.25 lbs sand
20.25 lbs soda ash
5.25 lbs potash
9.06 lbs hydrated lime
2.18 lbs 5 mole borax
Im considering upping the potash and decreasing the soda per and E&T's values but thought I'd see if any of you (perhaps Pete himself) had any suggestions.
Thanks in advance!

Pete VanderLaan 11-06-2019 11:20 AM

That's an old recipe of mine but it would work. I'd note that it lacks alumina which was a lot of my abandoning it.

It's slow to fine out without nitrates. Sulfur is not exactly a fun material to work with.

Kenny Pieper 11-06-2019 04:23 PM

Paul my experience is that adding a small amount of zink makes this carbon amber more of a rich honey color. But too much and repeated cooling and heating will create a zink sulfide which is opaque and generally looks like shit. I add some sugar also for reduction and more carbon.

Paul Stout 11-06-2019 05:07 PM

Thanks Kenny, Ill make a note. Theres a bit of zinc oxide in the East Bays batch and I had wondered if that would adversely affect the color but I guess not, thanks for the tip

Paul Stout 11-06-2019 05:11 PM

Would adding black tin and sugar to East Bays batch create enough reduction to get the color to take, or do I just need to go ahead and make this unoxidised batch?

Pete VanderLaan 11-06-2019 05:29 PM

I never used this formula to make sulfur colors. It was promoted for copper rubies and silver glasses.

Josh Bernbaum 11-06-2019 06:47 PM

If you have some of East Bay's regular batch to spare, why not do a test melt with it, 10 lbs. or something that's easily multipliable (is that a word?) And add the sulfur and sugar and black tin to that and see what happens. Or doesn't happen. Or how much it smells afterwards. A side note is that I've gotten some brown to amber tones on SP's oxidized batch by using quite a bit of manganese and a bit of iron. I think that's the manganese browning up on the all-sodium base which is SP.

Paul Stout 11-06-2019 07:17 PM

I tried that without the black tin, just sulfur and sugar and it resulted in no color. I was going to try it with black tin, but Ive decided it would be better if I just make an unoxidised batch. Also a good learning project for me.

Paul Stout 11-06-2019 07:22 PM

Quote:

Originally Posted by Pete VanderLaan (Post 145813)
I never used this formula to make sulfur colors. It was promoted for copper rubies and silver glasses.

noted, thank you

Ed Pennebaker 11-07-2019 07:47 AM

I usually found the carbon sulfur amber didn't need a fining agent. Maybe it produced enough bubbles to clear on its own? By the time it was up to 2350 there were just a few larger bubbles on the surface and didn't have any seeds. I thought is was one of the nicer colors to work with and easy to melt as a reducing color. I used powdered charcoal from a local charcoal plant (they dusted off their shelves to get powdered charcoal for me).

Pete VanderLaan 11-07-2019 08:50 AM

what you don't say Paul is how much sulfur you used on that first attempt. I recall making sulfur ambers using ordinary plate glass forty years back. I'm not clear at all that you need the absence of nitrates to do it. I would think that saltcake would give you some fining assistance if you tried it. I don't do it simply because the color is not to my taste. I would imagine that Helmer has lots of formulas for it.

Paul Stout 11-08-2019 10:50 PM

Quote:

Originally Posted by Pete VanderLaan (Post 145813)
I never used this formula to make sulfur colors. It was promoted for copper rubies and silver glasses.

Quote:

Originally Posted by Pete VanderLaan (Post 145820)
what you don't say Paul is how much sulfur you used on that first attempt. I recall making sulfur ambers using ordinary plate glass forty years back. I'm not clear at all that you need the absence of nitrates to do it. I would think that saltcake would give you some fining assistance if you tried it. I don't do it simply because the color is not to my taste. I would imagine that Helmer has lots of formulas for it.

I used .04 percent sulfur in Jims Regular Batch and .005 percent sugar. I also added .09 percent soda ash. Too little perhaps?
Perhaps Ill try once more at .1 percent before moving on. Volf mentions potassium improving the color. I'll look into Helmer, and salt cake thank you for the suggestion.

Pete VanderLaan 11-09-2019 10:14 AM

If you are actually mixing my old clear formula, be careful not to confuse Calcium carbonate or whiting with hydrated lime. They yield totally different percentages of calcium oxide. The lime should be a type N and food grade is best.
Percentages of colorants are usually OK up to .1percent, not always. .04 is pretty light unless you have certain things you're trying to do. If you have "recipe Book" translated by Finn Lyngaard, it helps show fundamental formulations pretty well. Watch out for his typos. They're killers.

Greg Vriethoff 11-10-2019 04:34 PM

Quote:

Originally Posted by Pete VanderLaan (Post 145806)
Sulfur is not exactly a fun material to work with.

I'm just trying to follow the logic here. I'm having a hard time seeing the sulfur in the formula posted. I assume it would be from the potash, but not all potash contains sulfur (correct?).

I know there's a lot I could be missing due to lack of experience.

Pete VanderLaan 11-10-2019 04:51 PM

The sulfur would be an additive to the basic mix. I'm suggesting that .1 percent would be a better place to start. I have also suggested elsewhere that if you use SP87 color base that it already contains a good deal of zinc so that adding more is not necessary. As it stands it could be a mismatch with SP87.

Josh Bernbaum 11-11-2019 10:19 AM

It also could be noted here that the SP color base is (I suppose lower) expansion than the SP 87 oxidized since it leaves out the nitrates and antimony. When I had a phone call with Tom years ago I think I remember him mentioning adding 1.1 lbs. of soda to the 100 lbs. of unmixed color base to get expansion back to where the 87 oxidized is. I still haven't used any of the 1000 lbs. of his color base I have taking up precious space here though..

Pete VanderLaan 11-11-2019 11:01 AM

Use Potash instead. It will help the color.

Paul Stout 12-26-2019 10:16 PM

So quite a few melts later, I thought I'd go ahead and share my results.
a)I was melting too hot and turning the sulfur into sulfur dioxide which is just seedy clear
b)In East Bays regular batch I was able to get a nice amber by adding 1 percent sulfur and having the sugar be 1.25 times the amount of sulfur. In the attached picture the "columns" are all the same sulfur amount with increasing amounts of sugars in the "rows"
c)I was quite surprised that the sugar amounts made such a huge difference in the color.
d) large amounts of sugar (like two to three times the amount of sulfur) melted glasses that went fleshy opaque almost immedietaely when working, but the cullet was quite beautiful deep amber red with white agate looking streaks. Im thinking that the extra sugar allowed the sulfur to start to develop zinc sulfates in the glass (though I added no extra zinc, there is some in the batch)
e)this is the first color I've had to really work for and am really happy with it, though I still want to try it in a potash glass as suggested by Pete. Im also drawn towards the thought of adding some silver to see how it affects the color. . . any thoughts?
Thanks!
http://talk.craftweb.com/picture.php...&pictureid=104


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