Wanhao includes two adhesive plastic sheets with the printer, I think it’s thin PEI. Print adhesion on the sheets has been excellent, and warping/curling is very little: < 100 microns of corner lift on a 30 mm box. I think this mostly indicates how great heated beds are, because I used to be getting whole millimetres of lift on an unheated bed with blue tape.
But I have some issues with the Wanhao print surface:
- It’s real expensive. The sheet itself only costs AU$4, but shipping it here to Australia costs AU$32!
- It’s vulnerable to wear. Just from one day of printing, the purge lines at the front-left already wore a groove into the material, I’d say it’s maybe 5-10 microns deep. I ended up putting a strip of blue tape at the front to protect it there, but any repetitive printing at the same place with have the same effect – calibration prints, for example.
- You can’t get the bed too hot. If I went above 50 °C, the PETG would stick far too strongly and I’d risk damaging the surface during removal.
- You feel bad about damaging it. I actually did end up cutting into the bed and removing a nice chunk from the center. Felt sad.
The sheet removed cleanly when the bed was warmed to 40 °C. I was about to put the second sheet on the printer but I decided to check the price of replacement sheets first. After I saw that $32 price tag, I decided that I’d give good ol’ blue tape another try.
Blue tape (3M #2090) on a heated bed
It works amazingly!
- Adhesion is great, which is typical for blue tape.
- Removing prints is so easy. They pop right off once the spatula gets under them.
- I can get the bed much hotter (near the glass transition temp of the plastic) without risking over-adhesion. I’ve run at 70 °C for PETG.
- Because I can run the bed hotter, I get even less curling than with the Wanhao surface, 35 microns compared to 58 microns!
- Even after many heating and cooling cycles, the blue tape still peels off cleanly.
It really is true: blue tape is forever.
I’m going to write a guide to how to use blue tape properly.