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Holiday Notice - President's Day

Accu-Cast will be closed Monday, February 19th in observance of President's Day. Resuming normal operations on Tuesday, February 20th.

Holiday Notice - Easter

Accu-Cast will be closed Friday, March 29th in observance of Easter Weekend. Resuming normal operations on Monday, March 30th.

Holiday Notice - Memorial Day

Accu-Cast will be closed Monday, May 27th in observance of Memorial Day. Resuming normal operations on Tuesday, May 28th.

Holiday Notice - Independence Day

Accu-Cast will be closed Thursday, July 4th and Friday, July 5th in observance of Independence Day. Resuming normal operations on Monday, July 8th.

Holiday Notice - Labor Day

Accu-Cast will be closed Monday, September 2nd in observance of Labor Day. Resuming normal operations on Tuesday, September 3rd.

Holiday Notice - Thanksgiving

Accu-Cast will be closed Thursday & Friday, November 28rd - 29th in observance of Thanksgiving. Resuming normal operations on Monday, December 2nd.

Holiday Notice - Christmas

Accu-Cast will be closed Monday, December 25th in observance of Christmas. Resuming normal operations on Tuesday, December 26th.

Holiday Notice - New Year's

Accu-Cast will be closed Wednesday, January 1st in observance of New Year's Day. Resuming normal operations Thursday, January 2nd.

How much alginate do I need?

As you may know, there are two basic types of alginate molds- The "Bucket Mold (hands, etc.)" and the "Layup Mold (faces, torsos, etc.)".


  • Baby Hand Cast: ~3.5 ounces in a 16 ounce cup with 14 fl. oz. of water
  • Child Hand Cast: ~6 ounces in a 32 ounce cup with 26 fl. oz. of water
  • Adult Single Hand: ~1 pound in an 86 ounce container with 2 quarts of water
  • Adult Double Hand: ~1.5 pounds in a 4 quart container with 3 quarts of water

Family Hand Cast: ~3 pounds in an 8 quart container with 6 quarts of water

  • Face Cast: ~4 ounces
  • Head Cast: ~1 - 2 pounds
  • Half Torso Front: ~.75 pounds
  • Full Torso Front: ~1.5 pounds

For a more detailed answer, read on.



In a Bucket Mold, alginate is mixed and placed into a container (bucket). The body part (a hand is a perfect example) is pushed down into the alginate to make the mold. The bucket holds the alginate and keeps it in place.

In a Bucket Mold, the alginate fills the space between the hand and the inside of the bucket so the smaller the bucket, the less alginate you will require. The bucket must be big enough so the body part doesn't touch the inside or the bottom, but not overly large. (Just imagine how much alginate you'd need if you did a hand casting in a bathtub.)

The easiest way to calculate your alginate requirement is:

  • Fill the bucket with water
  • Put the body part in- allowing the excess water to flow out
  • Measure the remaining water
  • Since a pint of water weighs almost exactly 1 pound, for every pint (16 fl.oz) water you have left over, use 1/4 pound of alginate. That's our 4:1 ratio

Remember, we recommend our 270-D, 370-SD, 380-CC, 390-S2 and 570-PGV alginates for bucket molds. Bigger jobs generally require more working time.


In  layup mold, the alginate is applied directly to the skin. Common examples of layup molds are face casting and torso casting. Layup mold alginate requirements are based on square inches of area to be covered by the alginate. Since alginate is usually applied about 1/4 inch thick, some simple calculations should give you what you need.

We have found that 1 pound of alginate mixed 4:1 (water to powder by weight) has a total volume of approximately 137 cubic inches. Mixed at 3.75:1 (our "thick mix") that figure drops to about 128 cubic inches per pound.

Now, since we are only applying the alginate 1/4 inch thick, we multiply those figures by 4 and get an approximate surface area coverage, per pound, of:

  • 548 square inches at 4:1
  • 512 square inches at 3.75:1

An approximate measurement of the area to be covered can be done by measuring the height and width of the area (in inches) and multiplying them together.

For example, my full torso is approximately 24 inches tall by 18 inches wide, or 432 square inches.

This area could easily be done with just one pound of alginate. Always mix a little extra because it is MUCH better to have a little bit too much than not quite enough.

A face is generally a circle about 12 inches across. That give us a figure of 113 square inches, so a face can easily be done with just 1/4 pound of alginate (actually 3 ounces is generally enough).

If you still have questions, please feel free to contact us. We'd be happy to discuss your project with you.

Categories: Accu-Cast FAQs