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African Animals Pattern Set.
Save $10 when you buy this three-pattern set. Use the patterns to create memorable gifts, or to bring a little bit of Africa to your own home
This video shows how to use the gelatin and glycerine mold-making material to make a mold. (You’ll find the actual recipe and mixing method in my previous post). For the model used for this mold, I used a scrap of clay I pulled out of my clay bucket. He’s a bit flat, and has no eyes, poor thing – but it worked well for the experiment.
The warm gelatin mixture did soften the Sargent Plastilina, but the clay hardened up again as the mold material was solidifying, so it didn’t seem to hurt anything. This modeling clay has a much lower melting point than most, so I did worry about it. But it worked just fine. And it’s so much less expensive than most oil-based modeling clays.
Cautions…
- As I mention in the video, you can’t use the gelatin mixture over unsealed WED clay. However, if you seal the model as I show in a previous post, it works just fine.
- And you can’t use the material as a brush-on mold, so it isn’t a good substitute for the Rebound 25 from the Smooth-on company. Sadly – that’s really nice stuff, but it’s so expensive!
But when I poured it over the half-face made with the oil-based clay, it worked really well. I did use a light film of petroleum jelly, just in case, but I’m not sure it was needed. I only pulled one plaster cloth copy from the mold, but I’m sure you could use it several times. You would need to be very careful to not wash the mold with hot water, of course, because that could melt the finer details. A small, lightly damp sponge would probably work if too many little bits of plaster are left behind when you pull your piece out of the mold.
This might be a cheap way to make a lot of blank masks for a Halloween-inspired workshop, and let the kids (or adults) finish them. If you happen to try that, make sure and tell us about it.You’ll be experimenting, of course. I am way too chicken to volunteer for something like that…
As I said in the video, I really don’t think this would work to reproduce paper mache masks. The wet paper mache sitting over the wet, yet solid, gelatin/glycerine mold would probably never dry all the way through. It may even stick permanently to the mold, the way my unsealed WED cat did. But I haven’t tried it, so I can’t know that for sure.
If you play around with this stuff, be sure to let us know what you think!
Some possible names:
Gelarine Mold
Glycetin Mold
Geli Cast
Hi Jonni,
Just tried making the glycerine, gelatin mold, followed recipe and instructions exactly but the glycerin separated from the gelatin. According to the bottle it was 100 % glycerine and the gelatin was not out of date.
What happened? Hope you can help…Need the molds for props for a play I am working on
Thanks,
Ruth
Hi Ruth. I haven’t run into that problem, and I don’t have enough experience with the materials to offer any advice. I’m sorry I can’t be more helpful.
How about Good gel or fussy gel for a name.
Good names, Doreen. I went to all the trouble of experimenting with this stuff, and then I never actually made anything with it. Have you tried it?
Hi Jonni,
Thank you for your website. I’m so glad I found it!
I’m looking for a mold for some acrylic models I’m making…do you think this mold will hold up? Have you had or heard of anyone who has had any experience with that? I’ve played around with silicone molds, but it gets expensive after awhile and hasn’t worked out as well as I’d like.
Thanks for any thoughts or suggestions
Jeanine
Hi Melva. I think some of the people I ‘stole’ the idea from have used it for resin castings, but I haven’t tried it myself. The material I mixed up for this video series was left on my counter, in uncovered mason jars. It has shrunk a little, but otherwise it’s just like it was when it was first made. I don’t think it will last through very many castings, though. It isn’t as strong as silicone. You might give it a try with something that doesn’t matter much, and see what happens.
I’m just starting to work with this so have little experience.
However, a few tidbits I found on the web, might help with using it as a brush on mold.
Chill whatever you want to brush it on, then brush on thin layers, re-chilling between coats if needed. After a few layers are built up, you may be able to apply thicker coats as needed without chilling.
I also found a recipe for gelatin, glycerin, gum arabic and olive oil for gummy worms. I might try versions with and without the gum arabic to see if it affects it much for molding and use as a gel printing plate.
Geli plates have a note that it contains some mineral oil which would probably help reduce evaporation and may help with durability as well. Adding some into the mix might make it feasible to use with paper mache.
Good advice, Julie. Thanks.
Hi Jonni,
Or maybe you could call it gel mold?
I was just reading about a reuseable gelatin mold at Observations Blog earlier, and saw that a Jonni had been there too, so I came over here. I am really interested in this for a reuseable mold making material. The method you presented seems less complicated. I just ordered Knox gelatin and vegetable glycerine from Amazon. I might try to make a mold from one of my Santas and then pour plaster in the mold. My Santas have a lot of undercuts, though, and they are already painted and sealed. Do you think this mold material might ruin the original? I haven’t made any paper mache clay since 2012! I’m really wanting to start making another Santa or two with the pmc. I haven’t tried your new paper clay recipe yet, and I want to play with that also.
Cheers,
Maggie
Hi Maggie. You will probably want to do a small test, to make sure the liquid in the gelatin mixture doesn’t damage the paint. You might need to use a release, and any oil would be difficult to clean off the original after the mold was made. Experiment first!
I left my jar of this material out on the kitchen counter, with no lid, all this time. There is no mold, but it has shrunk just a little as the liquid slowly evaporates. It’s really interesting stuff.
Plaster gets hot and may melt the ‘Gelatin Mold Medium’ (a possible name).
True – I hadn’t thought of that. The plaster cloth didn’t cause any problems, but poured plaster might. Good point.
You could name it Knox magic mold or magic mold melt