I have been looking at getting some painters tape to use on the glass plate for better print adhesion, and everything I read suggests the blue painters tape, such as this:
However, this white tape is considerably cheaper:
This looks like normal masking tape to me.
Is masking tape ok, or is the blue painter's tape preferable? If the latter, then why is that so? What is so special about the blue tape? Is it a different material?
When you use painters tape, you need to level your printer with the tape applied. You need to relevel if you change the tape type.
It's not any blue tape that printers love. There are basically two factors that make a tape useful:
Let's look at some different tapes and their suitability - from my own experience.
The original blue tape is actually ScotchBlue for delicate surfaces by 3M. It has a good surface to stick to and at the same time an adhesive that does not degrade to unsuitability by heating. The delicate surface one is just as good as the all surfaces type. But don't use the outdoor type, it is sealed too much.
FrogTape has an adhesive that has no problems with heating, the surface is sometimes a little smoother. Its green variant is about as useful as ScotchBlue, while the yellow variant is easier to remove - which can be an issue when the printhead is not calibrated correctly.
Generic painters tape is a can of worms - there are so many different ones it is hard to describe. I have had very good off-yellow rolls from the dollar store of the 'fine surface' type - as in the tape had a fine surface - and their adhesive was good and didn't degrade too much under heat. The followup roll was a little thinner of material and released under heat so it can be a hit and miss - it's ok for starting out though.
I also tried a roll of UHU painters tape of the easy remove type and it was horrible, as it didn't want to stick after the nozzle went over it once even on an unheated bed.
I even tried two blue colored tapes from different dollar/hobby stores. One was ok-ish and had a similar result as the good dollar store tape in look, but left a blue shadow on the base of the print after two or three prints. The other was showing similar behavior to other mild-adhesive/easy peel tapes.
It's not color that matters, it is the formulation. If you must use blue tape, spend the extra bucks for quality. Some bloggers compared other tapes, tested ScotchBlue vs Kapton, discussed the benefits of either, discussed the ScotchBlue tape in depth.
While in general, I prefer to print on the surface of my (blue) BuildTak (clone), I occasionally whip out painters tape on an unheated surface for very delicate prints: I remove the print together with the tape from the surface, which allows better handling. Sacrificing a layer of tape only costs some cents after all while breaking a print is hours and filament for much more money wasted.
Of course, I don't know what kind of tapes you have. My experience with blue tapes is, that they seem in general softer and "nicer" than white tapes. Their structure appears denser and they seem to have longer "furs" while the white ones are "dryer" and "sharper"
This surface makes the blue tapes I sourced more suitable as the molten filament catches more furs.
Here are magnified photos of my comparable tapes. Unfortunately, my microscope is pretty lame but at least we can take a look on closeups:
This comparison shows the lower density of my white tape better:
to complete the picture here goes angle photos which reveals some more details
above shows that this white tape is made out of flat plastic fiber as they shine when illuminated from different angles
this could lead to another question
is such tape melted in any way in contact with extruded filament?
worth to analyse...
To answer your question, it doesn't have to be blue tape!
To be honest, tape is not my favorite bed adhesion solution, there are plenty other options that work better than tape.
Often you'll see references to blue painters tape (of a certain brand) to be used as a bed adhesion layer because many people have good experience with that. I have tried several tapes, white/cream to blue from various vendors but found that neither of the tapes satisfied my personal needs. To name a few: cleaning, application, preparation, repair, tear-off, no glossy first layer, color of tape sticking to printed part, etc. did not make tape a favorite bed adhesion solution. Instead I've been printing directly onto aluminium and glass using an adhesive (3DLAC or DimaFix) to stick filament to the bed. Use a wet cloth to wipe residue off, spray can to apply a new layer, et voila, just print, it always sticks! Glue stick is also a possibility.
So while the community screams "use blue tape", you just cannot use any blue tape from any tape manufacturer. There is no standard to which blue tape has to comply. Generally, speaking from painting experience, many blue tapes release much more easily after use while the white/cream paper tape sticks better and often tears (but this is frequently the tape that is already applied on heated beds of many Chinese printer kits, see image above). Not all tapes are equal: I have used blue tape from a local cheap source that will not stick to the build plate when it heats up, even if properly cleaned.
I'm more inclined to think that the color of the tape is just a way to distinguish yourself from the market back when the first manufacturer introduced the tape. Now that it is more common, others have adopted the color mimicking the tape they want to copy. It is more about the adhesive than it is about the surface of the tape (as in: "tape is rougher than the substrate you stick it on"), also you read that many people using blue tape need to prepare it by cleaning it (remove waxy layer) and sanding it.
IMHO, you just need to experiment yourself with several solutions and see what works best for you, could be that the white/cream tape from a local source also does the job. So basically, your tape does not have to be blue, it has to work!
The second image isn't exactly painter's tape. Both images are types of masking tape, but the common manila/cream-colored masking tape vs the blue or green painter's tape typically has three features that make it less desirable for bed adhesion:
Again: those are only typical arrangements. You can get blue painters tape at the same narrow width as manila masking tape, and you can get wider or thin manila tape. It's more a matter of what you'll commonly find for sale, and in all probability the manila/cream-colored tape will work just fine.
