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Old 01-26-2018, 01:44 PM
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cullet shortage

Coming to a distributor near you and sooner than I thought . Now it's only Cristalica and they will not be able to keep up with demand.
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Old 01-26-2018, 03:26 PM
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Well, that's a game changer. Did you get an email?
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Old 01-26-2018, 04:34 PM
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Well, I talk to a lot of people, including distributors and manufacturers. This has been coming for some time and has to do with why I keep suggesting that the price has to go up. - a lot. Several suppliers are now out of Spectrum ( Really SP87 cullet) entirely which happened a little more quickly than anticipated. Olympic hoarded it and has the remaining supply. Phil went and raided Cristalica since he's not an idiot, getting Cristalia to violate its exclusivity agreement with Spruce Pine. Given Spruce Pine, that did not surprise me. I would have done something similar.

The only trouble with this scenario is that Dobern has a furnace that can't make enough cullet to supply America, let alone Europe. Dobern , last time I checked had no plans to change out furnace productivity even though they are in a giant building occupying a small corner of that place. What I have gleaned is that they plan to push the current furnace with no maintenance plans and that could well crater in a few years. They already had one unanticipaed shutdown two years back. Even so, it still comes up short five tons a day with demand. What do you suppose happens when demand vastly outstrips supply according to Keynes ?
Eveline and I have talked casually about starting a cullet supply. We looked at it a few years back and did all the math and figured out the supply chain across the pacific. Then, Spectrum resurfaced like Glenn Close in "Fatal Attraction". We bagged it and invested in bringing Cristalica to the US through Spruce Pine. I really tried on that one, got the exclusive and had a lot of difficulty with the melts coming clean. Coupling that with biz practices I could not cope with, I withdrew from that partnership with SP taking Eveline with me.
The Spruce Pine furnace had already failed spectacularly with apparently no desire to actually do it over right. That was too bad in my mind but it is what happened. There have been hiccups surrounding a restart but I think it would take a massive change in thinking and managing and a cash infusion of about 500K. I'm 67. I make my own glass. How do you get by? I don't need it certainly.

Now the line I'm seeing is one I have been concerned about for some time. I got news last night from one furnace maker that the Cristalica is eating the liners for his furnaces. I'm not surprised by that based on the borax/barium content of the goop. I offered Dobern a change in the formulation to affect the problem. They passed, which I expected. They have too much invested in Kuchinke and I get that. What I expect to hear next is that the pots are dissolving as well. The stuff is really very similar to Sys96 but has a higher expansion, around a 97. Sys96 was actually a 94.1.

If it was me as a small studio glass blower, , I'd suck it up and melt SP87 batch. Ever so much harder on the absolutely spoiled glassmakers of today. I currently know of no other startups even considering the issue. Oceanside next year is no answer. I don't particularly want to bring Eveline and the Shanghai group on right now although we have the capacity for raw glass now. . I'm tired of the way they get treated. In this community, China is viewed suspiciously. i know better. You get what you pay for. Just look at how many clear cullet makers have failed.

I may hold a class just based on making your own clear. I bet it would fill right up. Takers?
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Old 01-26-2018, 05:05 PM
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The cullet market seems so dumb.

Where else is there a ton of demand, prices that even seem fairly tolerant to increases, inventory that doesn't spoil and relatively inexpensive shipping? Yet the suppliers keep bailing.

I get that it's energy intensive with furnace equipment that wears quickly, but with the right engineering and energy costs this seems like it would be a pretty good business. There are a ton of studios who don't want to deal with batch and are willing to pay a pretty nice premium to melt cullet. (Cue Pete's rant about people like me wanting clear glass as easy as squeezing a toothpaste tube I appreciate the glass chem experts! I really do! I just want to be able to focus on my work, not the clear.)

I set us (Public Glass) up with a year's worth of cullet because I don't want to worry about gathering over my existing tons of cane and murrine with Crystalica. I just hope that Oceanside gets their production up and running during this year.
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Old 01-26-2018, 05:13 PM
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I don't think Oceanside is going to do it.

Cullet needs to be $1.75 lb to get anyone out of bed.
For something so simple, it's not. There's a lot that can go wrong, and does. Otherwise, I'd be on the phone With Eveline. She's a lot younger than I am.

Back before color rods, this was easier. You made your own color from the cullet you had or you made color based on your personal formula. Then the rod biz exploded without as much attention to physics as might have been made, but no one cared. Finished work was actually pretty cheap. Not true these days. You guys try to fit everything under the sun into a single piece and rarely test anything.

and, it's cristalica, not Crystalica...
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Old 01-26-2018, 07:01 PM
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I would definitely be down with the class on clear. Depending on the timing. I assume it would not be for awhile. My income got slashed by 2/3's at the start of the year because I'm just an adjunct, and can be thrown-away at a moments notice.
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Old 01-26-2018, 07:18 PM
Drew Hine Drew Hine is offline
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Class

I would take a class on learning to make batch from scratch. I have been melting sp87 for years. I would like to understand the materials and formulas. Sign me up
Drew
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Old 01-26-2018, 11:40 PM
Jordan Kube Jordan Kube is offline
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Quote:
Originally Posted by David Patchen View Post
The cullet market seems so dumb.

Where else is there a ton of demand, prices that even seem fairly tolerant to increases, inventory that doesn't spoil and relatively inexpensive shipping? Yet the suppliers keep bailing.

I get that it's energy intensive with furnace equipment that wears quickly, but with the right engineering and energy costs this seems like it would be a pretty good business. There are a ton of studios who don't want to deal with batch and are willing to pay a pretty nice premium to melt cullet. (Cue Pete's rant about people like me wanting clear glass as easy as squeezing a toothpaste tube I appreciate the glass chem experts! I really do! I just want to be able to focus on my work, not the clear.)

I set us (Public Glass) up with a year's worth of cullet because I don't want to worry about gathering over my existing tons of cane and murrine with Crystalica. I just hope that Oceanside gets their production up and running during this year.
It seems straightforward and simple but it's not. Spectrum had rail car service and capacity. Their process and customer service was shit. We'll see how Cristalica shakes out. No one is enthusiastic about the borax in the cullet.
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Old 01-27-2018, 07:13 AM
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Originally Posted by Jordan Kube View Post
It seems straightforward and simple but it's not. Spectrum had rail car service and capacity. Their process and customer service was shit. We'll see how Cristalica shakes out. No one is enthusiastic about the borax in the cullet.
********
Indeed and as to the borax they seem just about as responsive to the complaints as SPectrum was over the sys96. I'm sure the crucibles will be blamed pretty soon.

It takes railhead, ports hopefully, cheap labor, inexpensive fuel, excellent material prices, a decent chemist, lots of capital. The dollar has dropped almost 15% against the Euro since Trump took Office. That will make Cristalica a good deal more expensive as well.
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Old 01-28-2018, 07:02 PM
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You didn't see the announcement from Olympic back in October that Cristallica was, at that time, in the midst of installing a "new, larger furnace with increased production capacity"?

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Originally Posted by Pete VanderLaan View Post
The only trouble with this scenario is that Dobern has a furnace that can't make enough cullet to supply America, let alone Europe. Dobern , last time I checked had no plans to change out furnace productivity even though they are in a giant building occupying a small corner of that place.
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Old 01-28-2018, 07:37 PM
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"...the announcement from Olympic back in October that Cristallica was, at that time, in the midst of installing a "new, larger furnace with increased production capacity"?"
You mean this one?
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Old 01-29-2018, 06:43 AM
Eben Horton Eben Horton is offline
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cristallica should just steal the spectrum 2.0 recipe just as they stole it from Tom Littleton. problem solved.
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Old 01-30-2018, 11:50 AM
James Burts James Burts is offline
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Back to Pete's comment about possibly running a clear batch class--- I'd drop everything to come to that.
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Old 01-30-2018, 07:23 PM
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Basics of Batching Clear

Very basic - sand, soda, lime glass oxidised clear (so it will fine)

You want:

As close to 70% sand as you can get, usually in the high sixties due to necessary compromises.
As for sand, see if you can find Short Mountain silica. It works better than most. Usually found at pottery suppliers, just like everything else you'll need here.

At least 8% modifiers, usually lime because it's inexpensive but could be almost anything in the 2nd column of the periodic table.

Try to keep it under 18% total alkali (see 1st column of periodic table for alkalis), usually sodium for economy but it won't polish well or be as pretty without some potassium. If you have to go over 18% alkali (matching Moretti?) you can still do it without devit if you use...

Enough alumina to keep it durable. Nick Labino's rule for all soda lime glass...divide total alkalai by 8 and that's your alumina percentage. This applies to all glass. Go below this and eventually the glass will devit.

Add 0.2% antimony and 0.4% sodium or potassium nitrate so it will fine out.

----------------------------------------------

OK, now let's spend a little more money and get some way nicer glass.


Again, potassium. Yeah, it's a bit expensive but 3-5 % will make a noticeable difference in appearance and polishing. % 5-6 will give you a glass you can use as a color base with things like manganese purple and not have the color brown out.

Strontium is inexpensive and works well replacing around half the lime. It does nice things for the appearance of the glass. Very similar to what lead does but it's not toxic.

Zinc will brighten up even your basic cheap-o soda lime alkali only glass at around 2% with a big bonus of much added durability.

Lithium will make it melt like gangbusters even at very small percentages. 0.2% is enough to get the basic benefits, as in speeds melting, improves glass strength and reduces thermal shocking. The price is spiraling up daily but worth whatever you have to pay if you're melting in something under powered or want the benefits and an easy way to change working characteristics.

Of course, if you change things, you'll have to tinker with the amounts of other things to keep it compatible. See below about spreadsheets.


Want to change the working characteristics?


Lithium drops the viscosity and extends the working time of the glass.

Leave it at 0.2% or cut it out altogether if you prefer shorter and stiffer glass to work.

Want sloppy and long like SP? It has roughly 0.9 to 1% lithium so take yours up in that range.

Need to go the other way on that or just want it much stiffer? Add more alumina in tiny percentages. A little goes a long way.



To match expansions you'll want to track what you're doing in a spreadsheet. You're welcome to a copy of mine, it's open source and free. Email me because I don't think there's a way to post a working version here.

Changing the amount of sand can be one of the easiest ways to match an expansion number because one pound of sand in a 100 pound formula will move the expansion about a half a point. In my particular case it moves the expansion .6 per pound added or subtracted.


All the calculations in the world only give you a "ballpark" number for glass melts. The truth is in melting it and seeing what you get.

There are too many ever-changing variables to get a truly accurate number on paper.

If the first melt missed, then you go back to your E&T calculations to get a ballpark number of what you'll need to add on the next melt to raise/lower expansion.
Then you melt that and see what you have.

This is where the E&T numbers in a spreadsheet really shine, they seem to be even more accurate for this "adjusting" phase.
Sometimes it takes a third melt to dial it in where you want it, but rarely more than three unless something else among the variables has gone wrong and is messing with you. Stuff like thermocouples, melt times/temps., hyroscopic moisture in the chemicals, etc. etc.

I always assume I'm in for three melts to dial something in and I'm often pleasantly surprised when I hit it in two.


The more you can standardize your process and sources of supply the fewer strange surprises you'll have.

Water in your batch chemicals can change quantity with the weather and screw up your results.

-------------------------------------------

Be careful to balance thought with empirical experience...or in simpler terms don't let too much analysis get in the way of hands on experience.

This is particularly important with glass formulas/melting because everyone gets unique results depending on their location, equipment type, phase of the moon (kidding) etc.

Something I learned the hard way myself...

------------------------------------------

I mix batch in a bucket or small plastic drum cut in half. I use a drywall mud or paint mixer and a drill, cardboard with a hole for the shaft on top of the bucket to keep the dust down. Fast and some of the most complete mixing so far. If you want super-sanitation on dust issues the industrial supply houses sell plastic bucket caps that look like a womens showercap. You'll have to add the hole for the shaft. I mix outside so the dust just fertilizes the grass.

When I was mixing a lot of clear I bought an inexpensive Harbor Freight concrete mixer.

Use a respirator and rubber gloves at a minimum for your protection.

----------------------------------------------

I know, you want an actual formula. I'll include some screen shots of my spreadsheets for the basic and something fancier with zinc and strontium.
Attached Images
File Type: jpg Basic Clear.jpg (69.0 KB, 58 views)
File Type: jpg Basic Clear Fancy.jpg (69.9 KB, 42 views)
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Old 01-30-2018, 08:20 PM
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A perectly reasonable response.Hands on, it ain;t so easy and I wish it were.

I have to remember one of my color class students when I asked as it repeatedly failed: "what color is the black tin in your recipe?" and the answer is "White".

Seeing and doing really is believing. As Dave suggests, it's not hard thoeretically, but, doing it is sort of harder.
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Old 01-30-2018, 11:11 PM
Brian Wong Shui Brian Wong Shui is offline
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I can confirm that Cristalica is corrosive to refractories. Iíve gotten more casting corrosion in the past 4 months of Cristalica compared to the previous two years of SP87. Cristalica has been chewing out a door that was cast in Supermax MZ

The economics donít seem to be working out either. Working temps are higher, washing out any energy saving from not melting batch. Couple that with more expensive glass to start with and higher maintenance cost, it means that Iím switching back to SP87ER after this pallet is complete. A failed experiment in my opinion.
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Old 01-31-2018, 07:26 AM
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Brian:
How is it affecting your pot? Do I recall correctly that you have a moly as well?
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Old 01-31-2018, 12:36 PM
Brian Wong Shui Brian Wong Shui is offline
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Brian:
How is it affecting your pot? Do I recall correctly that you have a moly as well?
Yes to moly.

Crucible isnít too bad right now. Some pitting but the crucible only has 4 months on it. I expect this to accelerate as the crucible gets to middle age.
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Old 01-31-2018, 10:45 AM
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Quote:
Originally Posted by Brian Wong Shui View Post
I can confirm that Cristalica is corrosive to refractories. Iíve gotten more casting corrosion in the past 4 months of Cristalica compared to the previous two years of SP87. Cristalica has been chewing out a door that was cast in Supermax MZ

The economics donít seem to be working out either. Working temps are higher, washing out any energy saving from not melting batch. Couple that with more expensive glass to start with and higher maintenance cost, it means that Iím switching back to SP87ER after this pallet is complete. A failed experiment in my opinion.
Ouch.... thanks for the info. I guess that I will make the switch back to SP batch after I am done with my cullet....
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Old 01-31-2018, 10:57 AM
Eben Horton Eben Horton is offline
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Don't forget about Jim @ East Bay Batch. Aside from being a super cool dude, he can also provide a good alternative to Cullet.
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Old 02-14-2018, 07:53 AM
Andreea Virag Andreea Virag is offline
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Quote:
Originally Posted by Pete VanderLaan View Post
Well, I talk to a lot of people, including distributors and manufacturers. This has been coming for some time and has to do with why I keep suggesting that the price has to go up. - a lot. Several suppliers are now out of Spectrum ( Really SP87 cullet) entirely which happened a little more quickly than anticipated. Olympic hoarded it and has the remaining supply. Phil went and raided Cristalica since he's not an idiot, getting Cristalia to violate its exclusivity agreement with Spruce Pine. Given Spruce Pine, that did not surprise me. I would have done something similar.

The only trouble with this scenario is that Dobern has a furnace that can't make enough cullet to supply America, let alone Europe. Dobern , last time I checked had no plans to change out furnace productivity even though they are in a giant building occupying a small corner of that place. What I have gleaned is that they plan to push the current furnace with no maintenance plans and that could well crater in a few years. They already had one unanticipaed shutdown two years back. Even so, it still comes up short five tons a day with demand. What do you suppose happens when demand vastly outstrips supply according to Keynes ?
Eveline and I have talked casually about starting a cullet supply. We looked at it a few years back and did all the math and figured out the supply chain across the pacific. Then, Spectrum resurfaced like Glenn Close in "Fatal Attraction". We bagged it and invested in bringing Cristalica to the US through Spruce Pine. I really tried on that one, got the exclusive and had a lot of difficulty with the melts coming clean. Coupling that with biz practices I could not cope with, I withdrew from that partnership with SP taking Eveline with me.
The Spruce Pine furnace had already failed spectacularly with apparently no desire to actually do it over right. That was too bad in my mind but it is what happened. There have been hiccups surrounding a restart but I think it would take a massive change in thinking and managing and a cash infusion of about 500K. I'm 67. I make my own glass. How do you get by? I don't need it certainly.

Now the line I'm seeing is one I have been concerned about for some time. I got news last night from one furnace maker that the Cristalica is eating the liners for his furnaces. I'm not surprised by that based on the borax/barium content of the goop. I offered Dobern a change in the formulation to affect the problem. They passed, which I expected. They have too much invested in Kuchinke and I get that. What I expect to hear next is that the pots are dissolving as well. The stuff is really very similar to Sys96 but has a higher expansion, around a 97. Sys96 was actually a 94.1.

If it was me as a small studio glass blower, , I'd suck it up and melt SP87 batch. Ever so much harder on the absolutely spoiled glassmakers of today. I currently know of no other startups even considering the issue. Oceanside next year is no answer. I don't particularly want to bring Eveline and the Shanghai group on right now although we have the capacity for raw glass now. . I'm tired of the way they get treated. In this community, China is viewed suspiciously. i know better. You get what you pay for. Just look at how many clear cullet makers have failed.

I may hold a class just based on making your own clear. I bet it would fill right up. Takers?

Hello Pete,
and hello to everyone,

As Pete knows me, but the others in the thread might not, I must mention that I work for Cristalica and handle the sales worldwide, so I can get some direct info about the current situation. 😊
What Pete explains about production capacity was absolutely true for that past period of time when he knew of our furnace directly.
At this point, I also want to thank him for introducing us to the US market and the vast array of clients we are now happy to supply, via either Spruce Pine, or Olympic Color Rods.
I want to give an update to that, i.e. that since Pete and us have spoken directly, the larger furnace in Germany has been fired up to meet demand. During the past year, in parallel with Spectrum not producing any more, we have noticed a higher demand and this being said, we want to also take the opportunity and inform you of an increased production capacity (which we will gradually keep raising) and a renewed guarantee that our capacities are planned long-term so as to ensure that our Premium product is accessible and available to all the artists we admire. As such, we want to ensure you Ė our existing and possible future clients Ė that we will meet the demand for glass without problems, as we have planned.
About the borax issue, as Pete mentioned, we have discussed this at that point in time. As in Europe and in other parts of the world, this issue has never arisen before, we are now again looking into what we can specifically do for clients encountering this problem. Please kindly forward any such photos, questions and description of this to our direct distributors, Olympic Color Rods and Spruce Pine, so we get word of any questions you may have and see further steps in this respect together with our partners on the US market.

We hope you do enjoy working with our cullet and look forward to seeing you all in la bella Italia, at the GAS Conference in Murano!

Glass is magic.
Andreea Virag
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Old 02-14-2018, 09:55 AM
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Andreea,
I sent you an email.
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Old 02-17-2018, 03:37 AM
Durk Valkema Durk Valkema is offline
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The volatilisation of boron introduced by the addition of Borax, from glass at temperatures of 1100 C and above is substantial due to its vapor pressure.
As an example in E-glass 10 Ė 25% boron loss is calculated, water vapor has significant impact on the evaporation of boron.
Boron volatiles condensate between 400 Ė 800 C and form all sorts of borates along the way playing havoc with alumna silicate refractory.
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Old 02-22-2018, 08:43 AM
Heather Hepp Heather Hepp is offline
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I may hold a class just based on making your own clear. I bet it would fill right up. Takers?
I would take your class on making clear glass.
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Old 02-22-2018, 04:21 PM
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Originally Posted by Heather Hepp View Post
I would take your class on making clear glass.
Heather, I would get a copy of the 4th edition of Glass Notes. Pete wrote an excellent section in there about mixing your own glass. Next, the color making sub-forum here on Craftweb has some posts that are real gems of information. A little more time consuming is searching through the whole site for information but is also very rewarding. The glass notes thing is probably the closest thing there is to an instruction manual. Dave Bross has posted what looks to be a couple of nice clear formulas as a place to start. Expect to pay at least $3000 for the equipment and chemicals to get you started. I think I am paying $.55 a pound for the clear base I am using in the quantities I am buying in. Just as a spitball estimate I would add $.25 per pound in your labor to measure and mix.
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