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We bought a large lot of mixed equipment at an auction, and one group of items has us puzzled: they're something to do with candy, but they're positive, not negative. We're not sure if you use them to make impressions in some other material or if you pour something over them or what.

Some of them are loose, most are on a plexiglass backing. Some of the molds and the plexiglass have very small holes, presumably to let air out. I can't seem to find search terms that give me results for the right sort of positive mold, I get only stuff about silicon molds or fungus...

I'm not sure what the material is, some of them look like metal covered in plastic, some seem to be a very dense plastic.

UPDATE:

As mentioned in a comment, "CANDYCRAFT" is a Minecraft mod, so Googling that doesn't get any useful info. But the comments did lead me to try some different searches. The molds are labelled "Pauline Johnson CANDYCRAFT ####" and I found some local (Vancouver BC) results for a company that seemed to exist here called "Pauline Johnson Candy" or (maybe later?) "Pauline Johnson Confectionery" That makes me think the answer about them being masters for making silicone molds is most likely correct.

Loose molds:

loose molds

Molds on backing:

molds on backing

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  • 1
    Your update led me to a chocolate maker that started out at Pauline Johnson‘s company, which apparently made chocolate, (not just candy).
    – Stephie
    Dec 11, 2023 at 21:36
  • … and the company sells chocolate molds that could very well be made with the kind of positives you have.
    – Stephie
    Dec 11, 2023 at 21:44

3 Answers 3

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I’m not a candy maker, but I’ve seen a lot of ‘how it’s made’ type shows.

To make shaped gummy candies, they put a layer of starch down, then press plugs in to leave a negative space, then pour the jelly into the depression that was made. Once it’s cooled, they scoop the gummies out and shake them to release any extra starch. (The starch then gets passed through a mesh and re-used for the next batch)

It’s possible that there are other uses, as well.

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    That makes sense, and now that you mention starch, I think I've seen a How It's Made for gummies. But I wonder if there's also something else these are intended for because, e.g. the single figure you can see at the top of the second picture is about 8" tall (50s pinup girl shape). Dec 10, 2023 at 22:07
  • I can’t read the full info on the mold (looks like part of it is CANDYCRAFT 981), but you might be able to find it online with a description of what it is. Unfortunately ‘candycraft’ is the name of a Minecraft mod, so I don’t have enough to go on right now
    – Joe
    Dec 11, 2023 at 14:04
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    To me mold look more like ones for vacuum forming of negative forms (as in the other answer ) - to be useful for making imprints in starch those would need some sort of handle to pull it out - I don't see any way to safely remove shape on the pictures from the starch. Dec 11, 2023 at 19:24
  • You might want to post a quick pic - Something like this to illustrate; chatelaine.com/wp-content/uploads/2012/10/DSCF7182.JPG
    – Richard
    Dec 13, 2023 at 21:57
  • The plates are definitely not for starch impressioning: why would there be holes around the shapes? Maybe the loose masters are; would need to see the back. Could use them for either casting, vacform, or impressioning. It's kinda strange to have just one of each for casting/vacforming, but if you have a collection that are similar where they'd form a sort of set with similar size and detail (e.g. the 'eggs', the more detailed 'flowers', and the 'toys/stuffed animals'), producing them together might make sense.
    – Nick T
    Dec 14, 2023 at 16:05
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Might be as simple as they are durable masters for making molds (e.g. from liquid food grade silicone) that are then used to mold chocolate or candy but which have a limited useful lifetime due to tearing or other degradation as they are flexed to remove the molded item.

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  • I'm fairly sure that's the case for the smaller ones on backings at least
    – Chris H
    Dec 11, 2023 at 11:52
  • You wouldn't want to use liquid to make molds of the ones on plates/backings, it'd clog the little holes
    – Nick T
    Dec 14, 2023 at 16:07
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The small holes in the plates give away the manufacturing process to be used: vacuum forming (aka vacuforming or thermoforming). A sheet of polycarbonate (typical for food applications) is heated above an element until it starts to sag, then when soft it's quickly laid down onto a positive shape and a vacuum pump sucks it down tightly onto the surface. Shown below is an example with ABS (not for food).

Thermoforming animated GIF

The plates are probably meant to be used with some particular former, but as long as they fit comfortably over the vacuum bed, they'd probably work with whatever. Smaller items you can usually put flat down onto the vac bed, which usually has a mesh.

Alex French Guy had a video about creating positive molds and using a vacuformer to make custom chocolate bars. Depending on the overall dimensions needed (the sheet needs to be a bit bigger than your master) the cost of a machine can range from sub-$100 to a few thousand (for one of reasonable candy-mold size...obviously there are gigantic ones)

If you see any shaped piece of plastic with some depth to it, but is of pretty uniform thickness: 99% chance it was made with this process. A cheap rough mold will get smoothed out on the outside, which is often preferred as you get a nice exterior surface finish. Curves and such will be a bit softer, however.

On the other hand, if you're concerned about the inside surface quality, like for molds, the time spent polishing or texturing your master will show up on the end product. If you use a FDM 3D print as your master, you'll see the layers.


Another count heavily implying vacform is on the top plate with the art deco person you can see 'random' bar shapes on the flat areas. When turning the flat sheet of stock into a mold, the bars will add stiffness to the otherwise flat-and-bendy parts, making it more rigid and easier to handle. They would be pointless if used for casting.

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  • If it was for vacuum forming, would you also need holes going through any depressions in the plugs? Maybe it’s just the quality of the picture, but I only see obvious holes around the edges of the plugs. (I’ve only done vacuum bagging for composite work, not vacuum forming, and for that you use fiber mats to ensure airflow above the item, and the form/plug is airtight)
    – Joe
    Dec 11, 2023 at 23:31
  • I had a wonderful toy vacuum molder when I was a kid. Vac-U-Form. You bought these plastic squares - 4" or maybe 5" on a side, different colors. And you bought sets of molds - there were creepy crawlys, and little cars and boats and airplanes, all kinds of things. Lots and lots of fun, stayed fun over time as you made more stuff. Dangerous as hell - the thing heated up hot - easy to burn yourself. Which was part of the learning experience and part of the fun.
    – davidbak
    Dec 12, 2023 at 3:45
  • @Joe the positive masters (plugs) don't usually need vents unless it has a bunch of two-way concave depressions and the surface is very smooth. When the softened plastic drapes over the master, if there are any crevasses (like the cracks in the turtle shell, or even just a gentle), they're usually enough to let the air get pulled out. If there is a problem with the master after doing some runs, you can always drill a vent later. Unlike your composite bagging, the plastic isn't a liquid, so it won't perfectly seal unless your surface finish is extremely smooth.
    – Nick T
    Dec 14, 2023 at 15:53

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