Lili Krakowski on mon 26 apr 04
Ever since I was a tiny tiny child I have heard about the High Cost of =
Tin. And people have said: Ah, if tin were not so pricey...." etc.
=20
Every time this comes up, I just sigh. Because the whole thing has a =
certain untruth to it.
Leaving aside that one generally uses less tin when opacifying than =
using ziconium, pretending one uses the same amount, look at it this =
way.
By the pound tin oxide costs $11.50 or so. The frits cost about $2.25 =
a pound --all this when bought by the single pound. =20
Grabbing a recipe from a notebook:
Wollastonite 24 @ $.84
Neph Sy 36 @ $.85
Strontium 8 @$2.30
Flint 20 @ $ .50
Tin 5 @ $11.50
Cop Carb 2 @ $ 5.25
And let us pretend that instead of grams or % we are dealing with whole =
pounds bought BY the pound.=20
" Extended" as the phrase goes, the Wollastonite costs $20.16, the =
nephsy $30.60, strontium $18.40, Flint $10, Tin $57.50, Copper $10.50.
$147.16 for a scary 95 lbs of glaze.
Let me go on. Zircopax at $2.50 a pound and assuming you use the same =
amount as you would of tin, would cost $12.50, saving you a whopping =
$45. 102.16 for 95 lbs
Now. The rule of thumb seems to be that a 5 gallon bucket holds 3000 =
gms of dry glaze, and that is 3K, and a K is about 2.2 lbs.
So a bucket of glaze holds about 6.6 pounds of glaze. A pound of your =
glaze with tin costs 1.55 so a bucket full would be $10.23, and if you =
use the zircopax $7.10. =20
Now this is a relatively cheap glaze--and do not ask me why it has no =
clay, I would add 3% at least of Bentonite.
You know how many pots a bucketfull will glaze. So the extra cost per =
pot is tiny--and, to my way of thinking the beauty of tin is worth every =
penny.
You know as well as I that you can trim $3.13 from your budget somehow. =
(You'd look super with fewer lattes, dearie!)
Titanium is a different kettle of fish, because it also contributes =
beauty. I have been doodling with glazes opacified by tin and titanium =
in combo, and I love the look.....
And remember: A glaze using frits would make the tin seem even =
"cheaper."
Lili Krakowski
Earl Brunner on mon 26 apr 04
First, I agree with you that what ever the cost, the tin just doesn't cost
that much more per pot. However, I think you messed up a bit on your
calculations below. I figure a GALLON closer to 3000 grams of dry weight
NOT 5 gallons. (on the other hand, I usually mix 5 gallons using 10000
grams)
Earl Brunner
Las Vegas, NV
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Lili Krakowski
Sent: Monday, April 26, 2004 5:38 PM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Tin, zirconium, titanium
Ever since I was a tiny tiny child I have heard about the High Cost of Tin.
And people have said: Ah, if tin were not so pricey...." etc.
Every time this comes up, I just sigh. Because the whole thing has a
certain untruth to it.
Leaving aside that one generally uses less tin when opacifying than using
ziconium, pretending one uses the same amount, look at it this way.
By the pound tin oxide costs $11.50 or so. The frits cost about $2.25 a
pound --all this when bought by the single pound.
Grabbing a recipe from a notebook:
Wollastonite 24 @ $.84
Neph Sy 36 @ $.85
Strontium 8 @$2.30
Flint 20 @ $ .50
Tin 5 @ $11.50
Cop Carb 2 @ $ 5.25
And let us pretend that instead of grams or % we are dealing with whole
pounds bought BY the pound.
" Extended" as the phrase goes, the Wollastonite costs $20.16, the nephsy
$30.60, strontium $18.40, Flint $10, Tin $57.50, Copper $10.50.
$147.16 for a scary 95 lbs of glaze.
Let me go on. Zircopax at $2.50 a pound and assuming you use the same
amount as you would of tin, would cost $12.50, saving you a whopping $45.
102.16 for 95 lbs
Now. The rule of thumb seems to be that a 5 gallon bucket holds 3000 gms of
dry glaze, and that is 3K, and a K is about 2.2 lbs.
So a bucket of glaze holds about 6.6 pounds of glaze. A pound of your glaze
with tin costs 1.55 so a bucket full would be $10.23, and if you use the
zircopax $7.10.
Now this is a relatively cheap glaze--and do not ask me why it has no clay,
I would add 3% at least of Bentonite.
You know how many pots a bucketfull will glaze. So the extra cost per pot
is tiny--and, to my way of thinking the beauty of tin is worth every penny.
You know as well as I that you can trim $3.13 from your budget somehow.
(You'd look super with fewer lattes, dearie!)
Titanium is a different kettle of fish, because it also contributes beauty.
I have been doodling with glazes opacified by tin and titanium in combo, and
I love the look.....
And remember: A glaze using frits would make the tin seem even "cheaper."
Lili Krakowski
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David Hendley on mon 26 apr 04
Actually, the cost difference in opacifying with tin oxide verses
Opax, Zircopax, or Ultrox is much smaller than Lili's calculation
implies.
The zirconium opacifiers are manufactured in different strengths,
but, generally, twice as much is required to produce the same
opacity as a given amount of tin oxide.
Really, if you are making handmade pots, the cost of the glaze is
insignificant, no matter what the ingredients.
I sometimes hear people complaining about the cost of cobalt oxide
at $30 a pound or cadmium inclusion stains at $45 a pound.
Big deal - so a $20 mug costs 8 cents to glaze with a dark cobalt
blue glaze, verses 3 cents for a cheap celedon glaze.
And, not to pick a nit, Lili, but a 5 gallon bucket holds way more
than 3000 grams of glaze. Most people mix up 10,000 gram batches,
and that still leaves lots of room at the top. For my most used glazes,
I mix up 15,000 gram batches in 5 gallon buckets.
David Hendley
david@farmpots.com
http://www.farmpots.com
----- Original Message -----
Ever since I was a tiny tiny child I have heard about the High Cost of Tin.
And people have said: Ah, if tin were not so pricey...." etc.
Every time this comes up, I just sigh. Because the whole thing has a
certain untruth to it.
Leaving aside that one generally uses less tin when opacifying than using
ziconium, pretending one uses the same amount, look at it this way.
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