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Hi there,
I'm new in the business of casting babies’ hands and feet. Please give me some advice on the following issues:-
1) How to avoid bubbles and holes in the plaster cast even though I have tried tapping the container dozen of times in order for the bubble to escape.
2) What is the best time to demold? I have try to demold after 3 hours, but sometime the surface of my hand cast is still wet (especially on rainy day) and i loose all the hand prints? Any idea why?
3) Should i touch up or repair my cast straight after demold or? I have tried to touch up the little holes straight after demold and i found that the cast is still very weak and i end up causing more damage. (Scratch all over the hand cast cause from my fingernail and toothpick when i was trying to get rid of the alginate)
4) What is the best way to touch up or repair holes, bubbles, missing finger and broken finger?
5) Should I apply the clear sealant before or after painting?
6) What is the best way to level the base of hand cast? Should I do it while it is still wet or when the cast is completely dry to avoid loosing the details?

Thank you.

Cheers
Su Bee

Hey SuBee, if you still have too many bubbles left after tapping to mold, you may be mixing your plaster too vigorously, creating a lot of bubbles in the mix. When taking into consideration that it takes so long for your plaster to set, you may have extra moisture in your mold itself before casting. Make sure you allow any moisture to drain from your mold before pouring in the plaster and your de-molding time should lessen.

The alginate should come free from the plaster without the need to scratch it with your fingernail. A dental pick will help you remove small pieces that might get caught in the cracks.

When working with plaster, I like to use Spackle to fill in small air-bubbles that may occur and Elmer's Glue works great if a finger should break off.

Always seal plaster before attempting to paint it or the paint will peel away. I like to use shellac to seal plaster after it has thoroughly dried. Leveling can be done at any time after releasing the cured plaster cast from the mold, just make sure the surface is not damp before working with it.

Happy casting. ~ Joe

Hi Joe,

Thanks for your reply. I normally wet baby's hand before taking the mold. Sometime i forgot to shake off the the excess water on baby's hand. I guess, this might be the cause of the excess moisture. I will take note on this in my coming cast.

Regarding the mark on hand cast, it is because i use the toothpick to get rid of the alginate on difficult area and accidently touch with my fingernail, and the plaster is stil wet and weak , therefore leave mark.

Thanks again and i will work harder on my next cast

Normally, there is no need to wet the baby's hand beforehand.
On the rare occasion that the baby was born with premature body hair, use a skin cream instead of water.
Hope this helps.