Hello, has anybody had any experience with making thin plastic sheets for thermoforming or vacuum forming? I’ve seen you guys extrude very large sheets but I’m wondering if anybody has been able to press them constantly thin, at 1.5mm and thinner? I am working on making a steel mold with 12 ton shop press to see if it may work. Any previous experience may help tremendously. Thank you al in advance!
I’d try using rolls – heated or not – and pull it through various stations like it’s done for filament. I think that’s how it’s done in the industry. That would give you perfect control over thickness and with some fiddling also temperatures. The device it self is pretty simple; assuming you’ve got it heated and in some shape already. If think you will need 2 feeding rolls and another for the final thickness; just as you would do pasta
right, thanks for the update and inspiration. It just triggered to get an older project of the drawer. With some luck you can build this in Sept. already for below 400$. thanks again.
Will be over the next few months. I am first building a custom compression molding unit out of a shop press. Having molds made has been taking out all my funds as soon as they come in. Many plans are being slowed due to lack of funding. I’m in the process of opening a government grant funded non-profit here in Las Vegas NV. Where I’m placing shipping containers in the areas with most poverty and pay them 130%-200% market value for pre cleaned plastic, de labeled, with no adhesives. That I’ll be able to mold with out having to extensively clean. That sheet making idea will be soon though I just have to build out this machine and buy a granulator and make my miniature wash-line.
Im mainly doing this here where I live first due to the fact that nevada won’t take household plastics to be recycled. It is very sad that laws like this are in play to de motivate people to actually recycle
Here’s a very poorly drawn rough draft of the process I’m thinking of. Essentially, this would replace the need for an industrial sheet extruder. To be able to use custom plastics to vacuum/thermoform.
Found a video of a guy doing just that with a pasta maker!
I believe it would work better between two sheets of thin metal. Will be testing in the coming months.
Would like these sheets to be 1.5mm for thermoforming cups and lids. Only reason I mentioned hydraulic press is because I’m building a compression molding unit out of one currently and was thinking I could just ad an another attachment to make a mold for a 1.5mm thick 18×20 inch plastic sheet. Apply heat and granules then press. After cooling or even while still warm could then thermoform/vacuum form. That’s my hope but I believe your right in having to do another forming/rolling process perhaps between 2 other thin metal sheets.
yup, something like this; a little big for a start
1. get it in a flat shape (oven)
2. roll it through such device (or a pasta machine for a start
3. put in a less dramatic press, to retain the flatness; it will bend over time otherwise; expect a long cooling time, hours. inflatable sacks filled with air or fire-hoses could do a great job as well since it’s applying pressure more equally than other candidates like hydraulic
4. re-iterate until you’ve figured all the times and parameters
5. when it’s looking promising you can start tuning the process; for instance multiple rollers, heated rollers; experiment with cooling…
a few steps are mutually shared with other methods; i recommended this because building up a 12 Ton press might go nowhere; i consider hydraulic as last resort; it’s brute force often at some points only; rather useless in your case; depends how big your sheets have to be of course.
I’m thinking I could use something like this? Or a few of these side by side? Not sure how I would feed with out making big mess. What’s your thoughts? Thanks!
i’d test this on a smaller setup first; possibly you can’t create enough friction … however, you need solid rolls and even 3-4 cm diameter can still bend over 1meter. there are actually ready-to-go devices for other purposes i can’t remember anymore; in the 50 cm range; possibly it’s sitting somewhere in a shelf of a machine trader for apples
Interesting, I was hoping to just compress if possible, Ive never made pasta before. lol I am looking into many options. I wonder where I might get some large smooth metal rolls that could do the trick. Thanks.