Injection Molding take 2

Last year I started the process of looking at injection molds and I started with a tiny hand cranked machine. The overall success of that was terrible and the machine itself was cheap and the process was a mess, so I wanted to go a big bigger with actual pneumatic pressure. Once you go with a machine that can offer accurate pressure that is consistent then you get results that look good and can be replicated. The machine in the picture above is the machine I have ordered and will arrive next month so I can fully start testing this with the materials I have in hand.

So why not get this done through a factory? So getting anything injection molded from a factory requires a lot of money up front for every mold wanted (be it here in the US or overseas). Granted molds for factory use are Aluminium and last forever but they are very very expensive. So what if I wanted to do a couple of hundred mold pulls and not thousands, and did not want to spend an arm and a leg? Well that is where these machines come into play.

Started looking at machines I could use at home, machines that were not too expensive and have enough plastic grams to fill molds I have in mind. So what would I make with this? well a lot of things I currently print I could make stronger, faster, cleaner and lighter from a mold. For example I could make hollow noses, teeth, claws, glossy eyes etc just to name a few. The possibilities are pretty much endless based on how well you can make a mold and sculpt in 3d.

So what about the mold? I do have a cnc on the way but it won't go crazy on metal so I am going to take a very different approach to the molds themselves. Since 3d tech has improved a lot these past few years so has the resin used in SLA machines or just regular resin printers. Resin printers can print with extremely strong resins that are high heat resistance which is exactly what I need to create a mold that will last me a while. But even if the mold only lasts me 100 pulls I can print a few of the same and call it good. Overall this process is so much cheaper than getting molds milled out of metal and a lot quicker too.

I have a few resins I plan to test which I had read work extremely well for high heat but great resolution too. Some are a bit more complicated to print and others not so much. Will start with one that has great reviews from Siraya tech. Have used their resins in the past and been extremely happy with the result. Once I get the molds started I will start posting how I plan on using them.

So the part that resin molds will get the most stress is the area where the hot nozzle extrudes plastic and touches the resin. So how do I make the mold stronger? Get one of these and create your mold with this piece in mind.

https://www.busterbeagle3d.com/product/aluminum-injection-mold-sprue/9?cp=true&sa=true&sbp=false&q=false

Just this piece alone will allow my molds to last a whole lot longer. I went ahead and bought a few so I don't have to swap them out from mold to mold so much. Though if they work out really well I will buy a few more just to have them all ready to go.

Plastic injection has been sold as an idea that you cannot do at home but the answer is yes you can. It just comes down to how much you want to spend, how much 3d knowledge you have for mold making and do you produce enough volume to justify doing this. For us it is a no brainer and can't wait for this machine to arrive and review this unit.