Pneumatic Compression Molder aka sheet press

Precious Plastic Machine Development
#1

I broke several screw type car jacks while making sheets.

 

So I upgraded the frame to a 3 ton bag jack.

 

Excuse the prototype it looks horrible, needs better linear guides, and a bigger frame/bed

 

I got about 60usd of steel and a half kilo of weld rod to try it.

 

I will put cooling fins on the top and bottom of the mold sheet and a couple cooling fans.  I think active cooling while under compression will speed up the process.

 

I am currently extruding HDPE into a heated cook pot which keeps it molten until enough is extruded to use.

 

here is the video of my ugly prototype crushing some cans.

#2

That looks great. Is there an advantage to the air bladder compared to the air driven hydraulic jack? https://www.harborfreight.com/20-ton-air-over-hydraulic-jack-95553.html

Can you comment on the cook pot? I’ve been considering one for either melting or pre-heating for the injection machine. Did you add a better temp sensor and controller or just used what it came with?

Thanks for the update.

#3

re: the heat pot, I just used a stainless steel turbo cooker, drilled a hole in the side to pipe the hot plastic thru and used the existing controller.  I also put a silicone lined bowl inside to catch the plastic and transfer it.

 

I chose the air bag jack because the air over hydraulic press are too slow.  the plastic can cool before it gets formed.  Also those jacks are very expensive locally.  No reason for it, just local sellers mark them up a lot. Island economy and all.