I am looking for options to create custom molds for my chocolate bars. I did order custom molds that were quite inexpensive and they kind of work, but are not as sturdy and don't feel as durable as a poly-carbonate mold. I have no idea how much it would cost to have professional poly-carbonate molds made. Any suggestions/thoughts?
You may want to look at Tomric. I know they offer custom molds, although I have not tried them yet.
You can expect to spend at least $5000 for a set of 100 custom "professional" polycarbonate molds. The main cost is going to be making the injection mold master. This is tooled in metal and is made so that the molten polycarbonate plastic can be forced into the mold. As you might imagine, a mirror-smooth finish is required on the mold surfaces in order to deliver the perfectly shiny results on your bars.
You are right - they are much more durable than the thin thermoform molds you are familiar with. Which is best for your depends on many factors.
One option to consider is that there are tabletop thermoforming machines that cost well under $1000 that can handle plastic sheets at least as large as for a standard mold. The tooling costs for making a master for use in one of these machines is much, much lower than for an injection mold and you can make new molds for a few dollars apiece. Thermoform plastic sheets come in a variety of thicknesses, so you can choose between different thicknesses for different reasons - thinner plastic might resolve finer detail better, thicker plastic is more durable.
I looked into this for one project, and it cost about the same to buy the thermoform machine as it did to have someone do the work. They would make the master from a computer CAD (CNC) file we sent them, but if you have a local machine shop they might be able to help. (Or go to a technical training institute where the teach such stuff and see if you can get a teacher to get a student to do it for you ... not for free, of course.)
Hello Clay. This is very interesting and similar to a technique that I really want to learn. On a few of the high end chocolate sites I've seen (TotallyChocolate.com, for example), they're able to produce some incredibly detailed molds. I believe they're using some type of laser etching to produce this level of detail. I imaging that the cost to produce this level of mold is fairly high but definitely something that I'd be willing to invest in if I can learn and understand the technique. Any ideas on how I can investigate this process further? Thanks again for your excellent response to Geetha's question.
The process Totally Chocolate uses is patented. The site refers to engraving and molds so whatever they're doing they are able to get fine details in their masters and transfer them to the plastic molds. As they are short run molds it probably helps that they are using comparatively thin plastic sheets because they don't expect to be producing more that many pieces - which helps a lot.
I spent about 3 minutes looking for the patent. If it is a good patent, it will tell you what they are doing and how they are doing it. A good CNC device and/or laser cutter is a necessity, as is a very good understanding of the release characteristics of chocolate from the molds For example, vertical elements are best if not perfectly vertical, but slope outwards a fraction of a degree to make the release easier.
I would also ask the manufacturers of vacuum-forming equipment. They will have many of the answers you seek. Don't look for inexpensive hobby models. Look for models used by volume production shops and feature high vacuum draws.
Hope this helps.
Thanks Clay. I'll start seeking out vacuum-foaming manufacturers. I doubt if it will be easy but if i can accomplish this, i do believe it will be worth the effort. Thanks again for the guidance.
Thanks all for your help.
Your insight was very interesting, Clay - that it's more worthwhile to actually buy a thermoform machine than go for the high end molds. I will look into that.
There may be some machine shops or maker spaces in your area with cnc machines or 3d printers. They may be able to mill out molds (in the case of a cnc) or build up a mold (in the case of a 3d printer). If you are design inclined you may be able to generate the cam files yourself. Otherwise most machine shops will be able to draft the cam files for a fee.