Sheets produced with Heat press
Today, my 38cm x 38cm heat press arrived which I bought on Ebay and could not wait to try it out (my final goal is producing plastic plates/sheets as a raw material)
So here you can see the first two experiments using scissors-cut Polypropylene!
Unfortunately the back isn’t that beautiful and the front texture isn’t flat due to baking paper, but for the first experiment, I’m impressed!
Nicely done, @flo-2. Baking paper prevents the plate from being super smooth, but I would say the overall smoothness depends on how smooth the plates of the press are.
Yours looks like not compressed fully.
We used quite a big pressure, so the thickness was minimum and the overall compression fully flattened the paper.Toggle replies
All the plates that were taken out of the mould straight away got warped outward. This is caused by the outer area solidifying faster than the middle bit. The outer bit cools down, contracts and forces the mid out.
To make a flat plate, you would need to cool it while it is in the mould, or at least fixed between plates.
I don’t know how your press looks like, but I guess you can take the plate out of the press and still have it clamped till it cools down.Toggle replies
Thanks for the really helpful tips & tricks!!! Thanks to that I was able to produce another, nearly flat, ~22cm x ~22cm sheet, about 2mm thick. I used the washers for spacing, that way the sheet got evenly thick, the pen is for size comparison. I will however build a of mould for fututre sheets, that way I also avoid damaging lots of baking paper due to molten plastic.
Hey! I recently bought 2 stainless steel plates (330 x 330 x 0,8 mm) and since I had ~ 200g of shredded plastic laying around, I decided to do some further prototyping with my sheets. For Prototype #4 I used PP shredded with sieve (6mm) and made a 1mm thick sheet. I heated it for 10 minutes on each side at 190°C and cooled it off afterwards in cold water. The result I got was by far the best I had since then. The surface is flat and shiny due to the steel plate.
PS: Sorry for the bad image quality, I’m taking the pictures with my 8MP smartphone camera which doesn’t really know how to focus^^ 😀
Prototype #5 was made like #4, except:
– I didn’t use a sieve when shredding, I just shredded the plastic multiple times and took out too big pieces in the end.
– I used 2mm spacing inbetween.
The results look very promising to me, I just have to add more material next time to get the sheets superflat and somehow make them even flatter if possible.
… actually consists of 2 objects, they are made with the same material, the same temperature, have the same thickness, unfortunately both are not full size. However I really love the texture, the feel and the thickness (mostly perfect 2mm!)
Heat: 230-240°C, Material: PP mixed colors, heated 10 minutes per side.
The only thing to be aware of is air bubbles that can form when spreading out the material too much! Better to do it like shown on the first picture!
About the reflectivity of a sheet of plastic. Now I guess I understand why my plates are not so glossy. You have a thin sheet of metal with appropriate finish in contact with plastic whereas I have a thick metal plate that is polished appropriately, but not to a glossy finish.
Good, now as I understand it I can adjust the sheet press arrangement we have.
BTW – the plates you make get better and better. Any ideas what you’ll be making out of them?Toggle replies
@oceanplastic Yes, great idea! I will try that in the future, thanks! 🙂
@lululololala I have two metal plates (33x33cm) and inbetween I lay the plastic. To achieve steadily thickness, I used little plates with the same thickness that I layed inbetween the plates with the plastic. These pieces were 2.5mm thick, so my plastic sheet was 2.5mm thick in the end too. 🙂
All the best
I love your work! your sheets look amazing and the communication of the process is very clear as well 🙂
I’m thinking of using a heatpress inc. a low mold to be able to create different forms of tiles / thick sheets without needing to cut a lot of excess plastic.
Have you tried anything like this, or do you think it will be possible?
I would use this to make for example hexagon shaped or round tiles. I think it would be much easier if this was possible this way, instead of with the injection machine (although the injection machine obviously has a larger purpose range).
I’ve found this heat-press, which I think is a good deal (only €90) and has a good size to start with: https://www.ebay.com/itm/DIGITAL-HEAT-PRESS-MACHINE-T-SHIRT-SUBLIMATION-PRINTER-TRANSFER-12-X10-PRESSING/222513097837?hash=item33ced06c6d:g:aBAAAOSw9fRZv1V8Toggle replies
and hi @veradevera
unless you are planning on producing a sheet that is 2.5mm (not cm!) thick like flo-2, I recommend looking for an oven with compression to make tiles with molds.
flo-2 also has 0.8mm (wow) stainless steel sheets.
a t shirt press heats from the top—>bottom, so if your tile is about any thicker than 10mm, it could be difficult to get heat transferred evenly through the tile. the top part risks burning by getting heat transferred all the way to the bottom.
the heating process may include flipping the mold, but make sure the flakes at the bottom dont fly out!
using an oven with press/injection/extrusion is great because the surface area that the heat(or metal) that is in contact with plastic is relatively large, while the volume/thickness of plastic itself is kept relatively low(shredded or cut films).
i hope this helps 🙂Toggle replies
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