Since following the process described below I have not had any part to bed adhesion problems.
The filaments I’ve been using are PLA, PETG, ASA, and TPU.
The bed surface is the stock flexible magnetic steel sheet that came with my SV04.
Cleaning the magnetic bed surface.
Carefully remove the magnetic bed and thoroughly scrub the top surface with a plastic brush and hand wash dish soap in warm water.
Thoroughly rinse off all soap and dry both sites with paper towels. Do not use cloth towels that may have residue from previous washing/drying. Do not use facial tissues or wipes as they often contain lotions to feel soft on skin.
During and after drying, do not touch the bed surface. Grip it only by the edges or “handle”.
Replace the magnetic bed onto your printer
“Levelling” the bed.
Heat the bed to printing temperature then run the 16 point bed “levelling” mesh. I’ve found that if all values are between 1 an -1 in the area my print is going to occupy I’m good to go. Between 1.5 and -1.5 overall should be OK. Otherwise I adjust the height using the appropriate levelling screw wheels and redoing the 16 point check until I’m satisfied. At this point, SAVE the settings.
WARNING. Do not leave the ABL probe in contact with the magnetic bed for more than a few seconds outside of it’s normal cycle as it will likely embed itself into the surface and leave a divot after you pop it out.
If you want to use an adhesive such as “Elmer’s Purple Washable” glue stick, first cool the bed to room temperature then apply the adhesive to the appropriate area, as indicated in your slicer, while the bed is still cold.
Now bring your bed and nozzle up to temperature and start your print.
I hope this helps someone.
I’m new to 3d printing and am learning as I go. I’ve not found much help online that’s relative to the SV04. I’ll post things that I find helpful as I go but what works for me may not work for you.