Forum

When I mix alginate in a bowl, I'm getting a lot of air bubbles. Does anyone have a technique that will minimize air bubbles? Or for that matter, do air bubbles really even matter if they get in the alginate?

You need to avoid air bubbles. Mix small batches with a wire whisk. It helps to make the mix a bit thinner so the air can be moved away from the model. A thicker mix is likely to trap air. In case of an immersion mold when you put a hand into a container of alginate, remember that alginate mixed with water is a thick viscous gel. Try tapping the container on its side to keep the mix liquid and it allows the air to rise away from the hand.

If you mix with a whisk you will encourage air bubbles to form in the alginate. For large batches, the best thing you can use is a paint stirrer. For smaller amounts, you can mix it by hand with a spatula. Never pump the alginate up and down when mixing it because that introduces air. Stir it in a circular fashion instead or use a Jiffy type mixer, and whatever you do, do not over mix. You will always get air bubbles, so tap the sides of the mixing bowl before you apply the alginate to your model to help get the air bubbles to rise to the surface.

If you are doing a hand or a foot, you can continue to tap the sides of the container while the model's limb is in it to help get the bubbles to rise. The more air bubbles you can get out at this point, the less you'll have to worry about and have to re-sculpt later on.

I have no problems with air bubble and I use a whisk all of the time. Just don't move it in & out while mixing. I do not think you should use cooler water. But I agree, a jiffy mixer is the way to go if you are mixing big batches.