Does anyone here know how to make injection molds?

I can provide DWG/STP files, but looking to get some molds made, aluminum or steel.

Mold and Die making were/are considered the highest skill levels for machinists. The design of the objects will need considerable modification by someone with that experience to be likely to work for commercial injection molding. It is possible to DIY injection molding, but expect multiple iterations until you achieve a working production.

https://www.amazon.com/Secrets-Building-Plastic-Injection-Molding/dp/1878087193/ref=sr_1_1?ie=UTF8&qid=1484757868&sr=8-1&keywords=gingery+injection

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I’ve been looking at this myself for use with the Carbon Fiber parts I’m looking to make, and @wandrson is ABSOLUTELY correct. I’m fairly new to machining, but already I understand how and why mold making is considered high level machining.

Lock down your material choice. This is the first question you will be given from a tool shop. Not only does it drive the details of your design (draft angles, wall thickness, etc.), it dictates the mold shrinkage value the tool will be made to. You could get 1,000,000 parts from a steel tool. You could go aluminum even with loaded a loaded material. You may be able to cut some cost of you can find an appropriate pre-made mold base from somewhere like www.dme.net. That doesn’t answer you question, but just some things to consider.

Oh I understand, and believe me I expect to pay for the work. I just figured before I pay some Chinese factory to do it, I would see if anyone here had the skills and wanted to earn some cash. Consider it paying back to the community.

I’ve not got a lot of experience with the HAAS, but my understanding is that with the appropriate skills, it could make the molds, so I figured I would check and see if anyone of our makers had the skills and wanted to give it a go.

For this, it would be ABS plastic, something like ABS, Sno White (Lustran 348-012002). The parts are pretty simple by comparison to some. Keyboard key caps. Single injection, approximately .62 grams each, less than 1" in size in all dimensions.

Here are some sample images, sizes in MM

Well that didn’t work well did it!

Walter is right. That’s why IM dies cost $10K and up. And they earn that money.

EDIT: And it’s not just the machining. Designing the mating dies is an art all its own also.

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Add in that the machined part is really just a blank to make the mold from. There is still a lot of hand work left when it comes off the mill.

This is a simple enough part that you can make a soft mold on the HAAS.

Be sure to read the stuff that Protolabs puts out on mold design. They are a really good resource.

https://www.protolabs.com/injection-molding/fundamentals-of-molding/

Edit: The hardest part of your design is the feet, you definitely need a draft angle and you need to put a radius on the sharp corners.

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Yeah I don’t fool myself into believing that I have the time/skill to attempt a mold at this time. Hence my figuring I would see if anyone else wanted to take on the task to earn some spare $$$

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hmmmmmmm… this doesn’t look that hard, but I’m also going to echo @frank_lima
I’ll be at the space Thursday - lets chat about it then after HOURS of research.

Back in the day, I worked in an IM factory (running a molding machine). I have a vague recollection that the dies weren’t exactly interchangeable between the various machines. I believe there are some modular-ish cavities that can go into mold plates, but I’m not sure how you make a die that you know will fit the IM machine unless you know what type of IM machine is going to run the parts.

Did Protolabs address that particular issue?

have you worked with carbon fiber before?

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Complete tools are interchangeable between appropriately sized machines (shot size and platen size).

Master Unit Die type tools must be installed in the appropriate frame. Which sounds like what you are describing.

To be able to shop the molding job around, having a complete tool is the way to go.

There are a lot of options in tooling for composites. You generally don’t need a matched mold (core and cavity), and nonmetallic materials are good options for many reasons, mostly material and machining costs.

All the carbon fiber molds I’ve worked with have been either a single side that are vacuum bagged the compress the composite. There is generally enough difference in composite thickness that a uniform cavity thickness is going to over/under compress based laminate thickness. Whereas IM fills the cavity.

Note: composite parts I’ve worked with have been larger multi-layer lay-ups.

Yeah, true… with me looking at making structural parts for my motorcycles I just don’t have the faith in those other materials (such as the rims I’m going to make). I’m sure I could go cheaper on the mold material, but when the part is already $$$ why play that game if you don’t have too. Just my own personal thoughts on it.

Or better put - just my way of skinning this cat.

I was suggesting something like Renshape that is often used for composite tooling for its machinability. In the case of high tolerance structural parts the CTE mismatch between carbon fiber and steel/aluminum must be considered. Nonmetallic graphite tooling is commonly used for building aerospace structures because it matches the part being built.
If metal is a must, Invar is the metal of choice for carbon fiber parts. Its CTE very closely matches that of carbon fibers - near zero.

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