This Information Is Also Applicable To CONCRETE Molds As Well
Proper Preparation Techniques For Your Hypertufa Or Concrete Molds
PLEASE NOTE: These guidelines are applicable for both concrete and hypertufa molds. I use the term “hypertufa” for ease of explanation in this article.
Any hypertufa mold used in a project needs to be prepped before you can start patting on the mixture. Why? Because the wet mixture forms a vacuum when it dries and, simply put, will stay pretty well stuck to your mold if you’ve not applied some sort of barrier or release agent.
You Need To Use A Release Agent!!
The following products will do the job for you … as with most other hypertufa makers, you’ll have your favorite(s) on-up-the-road.
Wooden or Metal molds:
Hypertufa adheres to wooden or metal molds! Line these with plastic! If you don’t, you more than likely won’t be able to get the ‘tufa to release from the mold. And then it goes without saying (but I will) that you’ll ruin your project trying to get it to release from the wooden or metal form. I’ve read where a newbie ‘tufa maker used her expensive gourmet stainless steel cooking pot as a mold. She didn’t put a release agent on it and she could NOT get the cured ‘tufa off the pan. Ended up chiseling it off and finally gave up and threw out the now ruined pot!
Depending on the size and/or shape of a plastic mold, you’ve got a few choices you can use to allow the release of the hypertufa from the plastic.
Besides wrapping your hypertufa mold in plastic wrap, or large trash or garbage bags, you can use:
- Motor oil (new or used)
- Cooking spray (i.e. PAM is one brand)
- Vegetable oil
- Mineral oil
- A blend of equal parts mineral oil and corn oil
Spread a thin layer of any of these onto the mold. Don’t worry. The oils will not harm the ‘tufa and will not be noticeable after a few weeks out in the elements.
Terra Cotta pots and planters for molds:
In the same range of difficulty as using wooden or metal molds, only the brave and/or experienced choose to use terra cotta items. WHY? Because there is a larger degree of difficulty when trying to remove the new hypertufa pot. Without the right release agent, the ‘tufa will literally bond itself to the terra cotta.
(Yes, you can use plastic wrap if you want to which would make it easier to release.)
I have never used a terra cotta pot as a hypertufa mold, but from my extensive research, I can pass this suggestion along to you. It seems more than a few “advanced” ‘tufa makers use this procedure: You MUST FIRST soak the terra cotta item OVERNIGHT in water. Then apply a generous coating of the equal parts mineral oil/corn oil blend. Then pat on your hypertufa mixture.
By doing the "soak, then oil" procedure it is said that you will have no problem getting the hypertufa to release from the terra cotta.