BS: Math problem -- Help me please?

Subject: Math problem -- Help me please?
From: John Hardly
Date: 15 May 02 - 04:27 PM

I really hate to do this but, 1. I work alone and I don't have someone to bounce this off, and 2. if I'm wrong I waste about $80 in ceramic chemicals, and 3. I know some of you are math wizzes, and 4. (and this may be most important) I don't want to glaze 1000's of $$ of pots with the wrong formula.

Here's the situation.

I looked up from my chemical scoop to realize that my 500G weight was on the scale and wasn't suppose to be. Then I realized I was putting the wrong chemical in anyway.

So, here's the short version -- in one batch I have 1780 grams of a chemical that the glaze is only suppose to have 800 grams of.

In 4 other batches I have 1280 grams in the batch that is only to have 800 grams.

here is a list of other chemical and ther proper weights. Can you tell me what the corrected weight for each should be?

feldspar 4000 grams
kaolin 1920 grams
dolomite 1280 grams
zircopax 600 grams
bone ash 640 grams
iron oxide 80 grams

I know, I know......the math should be easy. But to quote David Wilcox, "The balance is no harder, it's just that you've got farther to fall!"

thanks for any help. Y'all were having a slow day anyway...

...weren't you?

Subject: RE: Help: Math problem -- Help me please?
From: Steve in Idaho
Date: 15 May 02 - 04:29 PM

Which chemical is the wrong weight?

Steve

And I don't do math but someone who does might need it *BG*

Subject: RE: Help: Math problem -- Help me please?
From: Mrrzy
Date: 15 May 02 - 04:31 PM

Don't forget to use Avogadro's Number!

Subject: RE: Help: Math problem -- Help me please?
From: MMario
Date: 15 May 02 - 04:33 PM

Should the iron oxide be at 80 or 800?

I take it the weights above are for a single batch and all the other chemicals are correct?

Subject: RE: Help: Math problem -- Help me please?
From: John Hardly
Date: 15 May 02 - 04:46 PM

sorry for the lack of clarity.

all the above chemicals are listed in their proper amounts. the chemical that I screwed up is Whiting. It was supposed to be 800 grams per batch but instead I put in 1780 in the first batch (before I detected the 500G weight on the scale), and 1280 in the other four batches (when I realized I had transposed the amount of whiting for what should have been the dolomite).

I won't further confuse by mentioning that I already had the initial proper amounts of feldspar and kaolin in the batches -- I can subtract. I just want some reassurance that my ratio and thinking is square.

again, thanks loads!

Subject: RE: Help: Math problem -- Help me please?
From: Mary in Kentucky
Date: 15 May 02 - 04:54 PM

For the first batch, multiply each component by 1780/800.

For the second (four) batches, multiply each component by 1280/800.

Example: feldspar in the first batch should be 8900g.

PS I tried to make a table, but my computer needs defragging and is VERY slow just now.

Subject: RE: Help: Math problem -- Help me please?
From: John Hardly
Date: 15 May 02 - 04:58 PM

Thanks Mary,

those are the ratios I arrived at too. I'll probably still test the glaze on a few pieces first, eh?

Thanks all, and my apologies for wasting the bandwidth just to set my mind at ease!

Subject: RE: Help: Math problem -- Help me please?
From: Mary in Kentucky
Date: 15 May 02 - 05:00 PM

No prob...just tell me how you play FreeCell!

Subject: RE: Help: Math problem -- Help me please?
From: GUEST
Date: 15 May 02 - 05:02 PM

It's not a waste of bandwidth. Pottery is a folk art.

Subject: RE: Help: Math problem -- Help me please?
From: Noreen
Date: 15 May 02 - 05:07 PM

Ok, first batch has 1780g when it should have 800g.
Therefore you have added 1780 / 800 more than you should have, =2.225
So, multiply all the other ingredients by 2.225 to get the same proportions in the glaze: -

feldspar 4000 g x 2.225 = 8900g
kaolin 1920 g x 2.225 = 4227.5g
dolomite 1280 g x 2.225 = 2848g
zircopax 600 g x 2.225 = 1335g
bone ash 640 g x 2.225 = 1424g
iron oxide 80 g x 2.225 = 178g

Likewise for the 4 other batches, you have added 1280g instead of 800g i.e. 1280 / 800 = 1.6
Therefore multiply everything else in the 2nd batch by 1.6 : -<

feldspar 4000 g x 1.6 = 6400g
kaolin 1920 g x 1.6 = 3040g
dolomite 1280 g x 1.6 = 2048g
zircopax 600 g x 1.6 = 960g
bone ash 640 g x 1.6 = 1024g
iron oxide 80 g x 1.6 = 128g

Hope that makes sense- feel free to check my calculations if you wish!

Noreen

Subject: RE: Help: Math problem -- Help me please?
From: Noreen
Date: 15 May 02 - 05:09 PM

I could have saved my time with the HTML *grin*

Confirms your thinking, anyway! Hope the pots turn out well.

Noreen

Subject: RE: Help: Math problem -- Help me please?
From: Sorcha
Date: 15 May 02 - 05:12 PM

Pot? Pots? Auction??? I love pot/pots. Or potted pots as the case may be. Course, Mr. the Cop has a wee bit of a problem with the pot part............

Subject: RE: Help: Math problem -- Help me please?
From: okthen
Date: 15 May 02 - 05:12 PM

If it doesn't work, you can always auction the pottery on behalf of mudcat?

Subject: RE: Help: Math problem -- Help me please?
From: John Hardly
Date: 15 May 02 - 09:53 PM

thanks Noreen, for going the extra mile! My figures check with yours.

Subject: RE: BS: Math problem -- Help me please?
From: Mr Red
Date: 16 May 02 - 11:14 AM

Boltzman's constant - and heat-work function? Mrrzy Avagadro was no potter!
Glib answer is throw it all together with wallmix and do test firings.
I used to love layering glazes - some would break through or be more fluid than the top one, some would go all crystaline white but thats the fun of it, the good ones were unrepeatable by anyone! This was all stoneware and some gas firings and sometimes reducing atmosheres. What temperature you going to?
I will consult at home (at the Library now and not easy to read/find on the screen). If I have an insight (or an incite) of a fresh answer I will post. I just llllllllloooooooove these challenges.
AND call me a pedant but this is an arithmetic puzzle, Excel here I come.
gotta dash ........... next surfer has arrived.

Subject: RE: BS: Math problem -- Help me please?
From: GUEST
Date: 16 May 02 - 11:23 AM

Miccah would be able to help you he works with chemicals.