A first layer test will tell you a lot about the adhesion of your filament and your plate. The simplest test is to take a cube primitive, scale it to 230x220x0.50mm assuming a 0.40mm nozzle. What this will do is print only one layer on the plate. If you have any areas where either the plate is contaminated, uneven or the heater is malfunctioning, it will display it quickly. Here’s a recent post on the topic.
It is important that if you’re just now seeing problems, contaminants accumulate over time. It could be as simple as just dust or cooking residue from kitchen oils, to humidity to smoke from one’s fireplace. Anything can pile up on the surface and one wouldn’t be able to see it.
I’m assuming that you did a bed level test just to rule out an uneven build surface although that is very unlikely.
With regards to your question about what plate is recommended. The most forgiving plate for PLA is a texture PEI plate. It’s just a nice surface to print on no matter what. But it is limited it comes to certain materials such as higher temp materials. It will work with ABS as an example but ABS needs help. So does PC and to a lesser extent, PETG. By help I mean glue or higher plate temps.
Having said all that, just remember that the very first REPRAP 3D printers only had two kinds of material and those were PLA and ABS. Neither one had the advantage of a heated plate and they used a wood plate with painter’s tape and guess what? The filament stuck. So we are spoiled in this current era of multi-material magnetically held build surfaces.
The point here is that you want to create a test model that mimics the problem you are seeing that doesn’t use a lot of filament. This way you can run repeated quick trial and error tests without wasting a lot of time and filament.
I might suggest the following test but do NOT change the temperature:
Divide your plate into four quadrants or strips. Trips might be better since if you create a strip model, it will have more length to contract thus causing more thermal stress and inviting greater warping.
- Strip one will be bare plate with no treatment
- Strip two will be covered with painter’s tape
- Strip 3, repeat strip one but this time apply glue to the bare plate.
- Strip 4, repeat strip two but apply glue to the painter’s tape.
Now print the model on each surface and watch the results. This will tell you a lot about how your filament and build surface are reacting to one another.
This might look like this on the plate after slicing. In this case, I might suggest a 150x10x10mm noting that under each model there would be a different surface. It would be best if you used the current profile that you are seeing the warping with and just create a second plate for the experimental models. This would ensure that you’ve not introduced any variables to your experiment.
