Just seeing the picture of the machine brings back the melted plastic smell. I remember trying to collect each one at the Milwaukee zoo, and inevitably breaking the head off of them before long.
I find myself coveting a Mold-a-rama machine to make molds for it :-). Injection molding is pretty expensive to do in small quantities, I would like to have a 'table top' machine where I could trade time for money.
And they are reasonably close in Scotts Valley. I'm definitely going to have to get one of those.
EDIT: Interesting that the Makezine article has a pretty big problem. It doesn't actually show you how to make the 'second half' of the epoxy mold. To make the second half, you would have to assemble the mold and then pour epoxy into the assembled mold. Depending on the material you'd probably end up some how pumping that epoxy in, and you would need to pull a vacuum on it to avoid bubbles.
For desktop use, it seems like mold-making combined with a lab heater for ABS/whatever you're going to use would make it cheaper-still.
I used to do investment casting with silver, and that's mostly the way it worked. ABS is much lower-temp and cools faster, so some experimentation with the "crucible" would probably be in order. But that's home-brew for you.
I've always found these machine fascinating, never seen one in person though. I am surprised the molds are aluminum instead of steel. Typically aluminum molds are considered suitable for smaller runs only. If they do 100 parts a day that's 36.5K cycles per year.
They have several machines at the Lowry Park Zoo, in Tampa, Florida. I got one a few years back—the hippopotamus that is shown in the article. I love it, and if I ever get back there, I'm going to get a few more. It was cool to do!
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[ 1.8 ms ] story [ 38.0 ms ] threadhttps://makezine.com/projects/make-41-tinkering-toys/diy-inj...
With this:
http://www.instructables.com/id/Home-Plastic-Injection-Moldi...
Alternatively, you can purchase a hand injection molding machine as mentioned in the above instructable, if you don't want to build your own:
http://www.easyplasticmolding.com/model_150/home.html
...for $1800.00. So - if you have more money than time, materials and skill - well, it's possible.
EDIT: Interesting that the Makezine article has a pretty big problem. It doesn't actually show you how to make the 'second half' of the epoxy mold. To make the second half, you would have to assemble the mold and then pour epoxy into the assembled mold. Depending on the material you'd probably end up some how pumping that epoxy in, and you would need to pull a vacuum on it to avoid bubbles.
Its a nit of course, but worth considering.
I used to do investment casting with silver, and that's mostly the way it worked. ABS is much lower-temp and cools faster, so some experimentation with the "crucible" would probably be in order. But that's home-brew for you.
Might the thermal properties of aluminum make it a better choice for these quick turnaround castings? Quick to heat, quick to cool.
Ended up being one of my favorite bath toys.
Memories.