Play-doh mold?

>>918975
Seems legit, but sculpy/femo/whatever its called in your part of the world might be be a better moulding material. Test both and see which shrinks the last. I guess play doh would be better because it would be easier to break away from the moulded button once the HDPE set if sticking is the concern.

You could also experiment with brushing talcum powder or flour inside the mould to prevent the plastic from sticking.

>>918978
Never thought about putting flour in the the mold, will try but suspect the flour will stick on the button, you think it could be washed off afterwards or just stay there forever?

File: 20151223_173846.jpg (370KB, 1632x1224px) Image search: [Google]

370KB, 1632x1224px

>>918979
I used talcum (finer grain than flour) as a release agent to resin cast pic related, some plugs for my ears. There is a very slight optical effect, but the plugs feel smooth to the touch. There wasn't a lot of talc suck to this when I pulled it and what was stuck on brushed off easily enough. Considering resin is runnier (reads, more easily conforms to fine details like grains of flour/talc) than HPDE I can't see you having any problems. Even if there is some fine surface detail you won't see it because the button isn't transparent.

I can't speak directly to flour, I only mentioned it in case you don't have talc on hand, but again, considering HDPE is kinda thick, I doubt it will be a problem. Just make sure you remove all excess talc/flour from the mould; Use a fine brush to spread it into the corners and brush out the excess then tap the mould on the table to make sure all but the finest layer remains. Should come up a treat!

>>918975
>pouring some liquid hdpd

One does not simply pour HDPE. At best it goes like hot glue. You have to either inject it into your mould, or place shredded plastic into your mould then place it into an oven.

>>918978
This guys right. Sculpy/femo/milliput/bondo/kneadatite will work without a release agent.
Cement/Concrete/Plaster/Clay will work, for a while, with a release agent.

Best cheap stuff is "Plastic Padding Chemical Metal" in the UK. And "Devcon Aluminum Putty" in the US. They'll take many shots of plastic without damage or release agent - they won't even complain.