Clay Recipe in Parts? Weight or Volume?

[DCross]

New to pottery and currently exploring clay recipes.  I found a stoneware recipe "IUS Shop Stoneware"  and the recipe is in parts.  Probably a silly question, but I am new and do not understand if these parts are by volume or weight.  Can anyone explain how clay recipes in "Parts" are actually measured out?

[Min]

Hi and welcome to the forum.

I did a quick Google search and found the recipe you referred to. For that recipe it is parts by volume not weight. So it can be a soup can, a pail or whatever, just use the same container and  measure each ingredient by volume with it. Are you looking to make a sculpture or highfire claybody or ?

[neilestrick]

If the recipe call for volume, then do it that way.

Measuring by weight will generally give you a more accurate, repeatable mix. Because powders can be fluffy or compacted, you can get different amounts each time you measure by volume. Measuring by weight eliminates that variable. This is why so many baking recipes call for 'sifted' flour (sifting gives the flour a more consistent density for measuring by volume), and why professional bakers measure everything in grams.

[DCross]

Thank both of you for responding - looking to make highfire claybody.  I full understand the accuracy of weight over volume, but with the recipe as listed it would be a wildly different formula on weight versus volume, that is why I questioned it.  I was just not sure when I see recipes listed as "parts" if it was weight or volume in general unless otherwise specified.  Again - thanks for the responses.  New to the art and trying to learn.

Edited April 16, 2023 by DCross

[Callie Beller Diesel]

Most often, I’d say 99% of the time, assume recipes are in weight. The only time you usually see volume measurements is if the recipe is an older one from the US (1970’s or earlier), or the end batch size is measured in hundreds of pounds or kg. 

If the person who originally wrote a volume based recipe was less concerned about precision, variability may have been acceptable, or even desired. Even 20 years ago, almost no one who was mixing their own clay was worried about end porosity. They were concerned with working properties and aesthetics.

[DCross]

Thank you Diesel...I have found several different recipes with various formulations.  Some by weight, parts, percentage, and one that was listed as proportions.  As a newbie it was a little confusing, but the one listed on The Claybucket site seemed reasonable, especially if a college is using the recipe as their primary clay and all components were readily available at my local ceramics shop.  I just did not want to mess it up and figured I would ask some folks who have been doing it for a while.   

[Callie Beller Diesel]

Parts, proportions and percentages can all be expressed as either weight or volume, but it’s more accurate to use weight. If you’re mixing a 300 lb batch of percentage based recipe from 50 lb bags of dry materials, sometimes it’s easier to just scoop some of it, because the 1 or 2 lb variance that might result isn’t a huge proportion or percent of that final weight. If you’re mixing a 10 kg test batch, you have to measure more accurately so you don’t throw your recipe off.

 

 

[DCross]

That makes sense, thank you.