A comparison of bed topping for ABS.
I’ve recently tried a couple different heated bed toppings, and i still have some experiences with others from earlier on. For each test, the bed was set as hot as possible without the print deforming from the heat - for me, that was 120C for the first and a gentle slope down to 105C for the remaining layers, with 105C reached about 5mm into the print. The bed is a standard Prusa PCB with a layer of 0.5mm aluminum and a 3mm glass sheet on top. My printer was deliberately left un-shrouded in the cold (~8C) basement to maximize warp. This is what i found:
Kapton tape: Probably the most popular option, as it is used by Makerbot and many other printer makers. Adhesion to the tape is usually excellent, and still fairly strong when fully cooled. However, the problem is usually that the tape peels itself from the glass before the print detaches itself from the tape, which generally means that you need to take care of the tape after each large-ish print. It often tears when trying to peel the prints off, requiring you to replace it. Seams between the individual pieces of tape are always visible on the print. Fingerprints ruin adhesion, so it’s best to wipe it down with acetone or alcohol before each print. Tip for replacing: Roughly align the whole length of tape without pressing it down, then run the thumb-facing curve of your index finger over the tape to stick it down without bubbles or creases.
PET tape: Popularized by nophead, since it is easier to get prints off when done. Which is true, but also means decreased overall adhesion of your prints. Useful for large production runs of small items. Somewhat limited availability.
Hairspray on glass: Didn’t work for me as the print completely broke loose below 110C. I might have used the wrong kind of hairspray, though, as there are many reports of hairspray working well. Oh, and it has a terrible smell to it the first time you heat it up.
ABS juice: Can be used on top of plain glass or Kapton. It absolutely didn’t work on plain glass for me (peeled right off), but with a layer of Kapton underneath, it did overall increase adhesion. Accumulates each time you apply new juice and prints will end up with a slight brim that needs to be manually removed. It will be visible on the bottom layer if you use a non-matching color.
Glue stick: My absolute favorite so far. Works well on plain glass - in fact, warp was reduced by about 50% when compared to Kapton, but prints still pop off once completely cooled. Can be used many times without maintainance, but the marks from previous prints might be visible on the bottom layer. You can barely feel that the bottom picks up a small amount of glue. Gives off a tiny amount of smoke/steam when first heated. It is water-soluble with warm water, so preparing the bed for a fresh coat is as easy as heating it to 30C, wiping it down with water and then (optionally) smearing new glue over it. Overall, it’s cheap, easy to apply without making a mess and has all the adhesion properties you want.
Up for discussion: What bed topping do you use and recommend?
