I am making an electronics enclosure and need a 2-4mm thin wall in some spots to allow for components like buttons and on/off switches to poke out. Can anyone advise on the best materials for creating such a thin wall? So far, I’ve only tried wood, both pine and red oak tend to break. I’m using a 1/4 bit, perhaps a smaller bit would create less stress on the stock? Otherwise, I was considering either HDPE or bamboo. I’ll be needing a material that comes in thicknesses of 1 inch. I’ve noticed that some materials don’t come in that dimension.
The object that I mill with my Shapeoko will not be the final product, it is actually going to be the mold for a silicone pour which will then become the mold for epoxy resin. Thus durability of what I cut is not the highest priority. I’ll only have to use it a few times.
For prototype molds maybe consider Renshape? It machines beautifully, holds detail very well, and the C3D blocks come in 1" thickness (though probably not in large enough pieces for your need)
Take a look at the different plastics. Be careful some don’t machine very well. This company has a good selection and you can buy cut sheets instead of full to save money. https://www.professionalplastics.com/
Does plug need to have thin walls? Hard to visualize where this would be required on something like an enclosure.
When I make molds and plugs, plastics generally have limited use for anything but the simplest of components. Plastics are difficult/impossible to finish(remove machine marks ect), and depending on material, potentially unstable after machining. HDPE isn’t great for thin wall and can deform as you machine it/release stress.
All around, tooling board is a great option. Renshape is a product line of tooling board materials, but there are many others. I currently use the CoraFoam line from Duna, as that is what a preferred local supplier carries. Note that tooling board still requires surface preparation, there are specific systems for this to take full advantage of a tooling board workflow, but you can use almost anything. For tool surfaces, I use densities upwards of #40.
MDF is a fine, albeit more labor intensive, readily available tooling material. Ultimately, it’s hard to recommend any particular material/method without knowing all the details. Being that your final tool is silicone, you’ve got a lot of flexibility.
I’d be happy to help or answer any questions. I don’t know that I necessarily have a specific process (maybe “style” and preferences), I’d say more of a limited tool collection (when compared to some of the true wizards). I’ve dabbled and/or worked with composites and custom tooling for most of my life. I’d say it’s a lot like cooking, you can substitute ingredients, methodologies ect to suite budget, time, and quality expectations.
I don’t have a project in mind, but that’s probably because I don’t know the process. I’d just love to see an example of someone here making a mold and casting something with renshape (or any other material).
I have to do some simple tools for a customer at some point soon, I’ll make an effort to take some pictures along the way and explain the process I end up using.
Assume you are making a low volume or single use tool, like a plug to make a mold. You can work right off of the tooling board. You’d have to select a board to suite your system, poly, epoxy, prepreg - high or low temp ect. Tool design is probably the most difficult part of the process, you need to be able to extract the part from the tool. Draft angles ect.
Machining tooling board is relatively straight forward, but finish quality is important. Once machined, it just needs a very light hand sanding. This is where proper tooling board density for the particular project becomes important. If the project required laminated tooling board, a low density board would sand faster than the lamination seams ect. The raw tool now has to be sealed. This can be done with a variety of products, but for the sake of a tooling board discussion, a tooling board specific sealer would be preferrable. Generally low viscosity, fast drying, easily sanded. Apply coats until surface is adequately sealed, sometimes sanding between coats to maintain desired surface quality. The tool can then be prepped with a variety of release agents. Wax or PVA are some readily avaible low cost examples. Ready for lamination.