Casting ABS plastic (possibly to recycle waste filament)?

I'm attempting a project to make a number of food safe parts. While ABS is considered foodsafe (for now...), most castable resins are not (and those that are, only for dry food). Then I had this crazy idea of finding high temperature (over 230 C) silicon, making a mold in that silicon with my ABS parts, and then heating up my waste filament and just pouring that in. This seemed like the best of both worlds, I would get rid of my waste, and have food safe parts. While I do use the waste for slurry, I always generate far, far more than I would ever need, but also not NEARLY enough to necessitate a mechanical recycler.

However in searching the forms I found a few old threads of people with this same idea that said melting ABS is not as easy as sticking it in your oven, Easy-Bake or otherwise, due to its amorphous solid state. The general consensus was that without heat AND pressure (usually obtained via extruding into a hot end), the ABS is difficult to keep at a liquid temperature, and difficult to heat without scorching it. However that was a while ago and I was wondering if anyone had any new breakthroughs on that. It would certainly be a green way to dispose of our waste filament. REDUCE, REUSE!

Failing that, anyone have any ideas for a castable foodsafe material that would work with silicon molds?

---

"Pfft. Third dimension... what dimension do we even live in?" - Charlie Kelly

I am trying a different approach, that is melting the plastic inside the silicon mold already hot. The temperature of the mold is controlled via arduino board or similar. I will let you know in some weeks if this works reasonably with ABS, PLA, PC, PETG, etc.

ABS might be food safe, but is the filament you purchased free from contaminants? How about your 3D printer? I think there is more to food safe products than the component materials, though I have only skimmed a few posts on the subject.

How about HDPE? That wouldn't help recycle your old prints but you could recycle your old milk bottles. There are lots of videos showing reusing hdpe. They have you heat it up and press it into a mold.

---

Newbie with Folgertech 2020 i3.