Manufacturing for Small Business and Startups
16 December, 2019
Please note, this article is focused on how individuals can make one-of-a-kind molds for unique baking purposes or selling in small quantities (eg. at local markets or fairs as a hobby) using a 3D printer and silicone casting techniques at home.
If you have an idea for a silicone mold you would like to mass produce and sell widely, please contact us directly on firstname.lastname@example.org, by using the chat box below, or by filling out our quote request form, as the process described below is not efficient or cost-effective for production at scale. Happy reading!
Silicone kitchen molds come in handy when you want to make unique pastry items. It is unfortunate that almost every bakery you walk into and every mold you can buy features the same items and familiar basic shapes.
Customizing molds with your original design is the solution for a bland looking cake! 3D printing allows you to think outside the standard mold shapes and use the farthest reaches of your imagination for design.
3D printing a master to cast silicone kitchen molds is not just for those with advanced degrees in CAD or who can afford the nicest 3D printer. There are places that can help you with the design and printing processes if you don’t feel up to or can’t be bothered learning how to do it yourself.
But for budding DIYers out there, read on!
The molding process starts with designing and printing a master to cast silicone molds for whatever it is you might be baking, whether it is a cake, bread, or batch of delicious cookies. While your limits for possibility are quite broad, it is important to know that 3D printing and silicone molds do have some boundaries.
You’re limited to a degree by size, and your design can’t have internal crevices or pockets, but in most cases if you can imagine it, you can make it.
Otherwise, take all the liberties you want when it comes to printing your mold masters. A never before seen shape or product could be right at your fingertips. Again, feel free to get in touch if you need help with CAD design or the initial 3d printing of the master. You might be surprised how cost effective it is!
It is important to note that molds are great at creating exact replicas of the 3D printed master model. Thus, any imperfection in the master that you have printed will be replicated as many times as you cast from it.
Choices abound when it comes to the types of silicone available. Rather than list them all here, we will provide a couple of quick tips about silicone measurements. If you can’t find food grade silicone at your local hobby shop, you can buy it online.
Silicone objects in general are measured on a scale called the Shore Hardness scale using a tool called the Shore durometer. A rigid item would be placed on the Shore D scale. A flexible object would reside on the Shore A scale. Silicones vary in hardness and the decision should be based on the desired final product.
Another choice lays ahead of the DIY mold maker – tin cure or platinum cure silicone? As their names imply, tin is the less expensive option. Why would you choose the higher-priced platinum cure? Well, if you are making silicone kitchen molds, you have to.
Platinum silicone is the way to go for a non-toxic, food-safe product (however please make sure that the silicone you are using has been certified as food safe by the FDA, this is really important!). Additionally, it is more flexible and easier to remove from the master. Finally, platinum cured silicone lasts longer than the tin cured variety, making it a wise investment long term and higher quality product despite the higher upfront cost.
The conversation detailing the process of mixing silicone would require a research paper-length discussion, but there’s plenty of info out there if you Google it. The most important tip is to be mindful of the “pot life” of a product. This is the amount of working time you have before the silicone begins to become solid.
Mixing and pouring should be completed prior to the pot life expiring. Do not plan on taking a break between these two steps.
It is time to pour! Simply aim for the lowest part of your master and let the silicone fill from bottom to top. The master should be full, unless it is two sided. Two sided masters should be filled halfway. Tap it to allow any bubbles resulting from your pour to escape through the top. Remember, your pot life is very important to how long you have to complete this step.
Pour mixed silicone from a high enough height that the stream becomes slow and thin. This will allow you to pop the dreaded bubbles that ruin a perfect mold. The end result of a bubble is a little bump in your finished castings. A degasser is the only way to definitively remove all bubbles but following this tip should help, as degassers are not something your average hobbyist or kitchen enthusiast has access to.
The sagest advice you could possibly get is to leave your curing silicone alone. One simple poke could result in a disrupted curing process and imperfect final shape. Add some time to whatever the suggested silicone curing duration states just to be on the safe side.
Remove the master model carefully to avoid accidentally ripping or breaking it. If any silicone made its way out of the master (flashing), you can cut it off with a sharp knife. Guess what? You did it. You successfully 3D printed a mold master model and silicone kitchen molds from it!