This comes before any thermal test print, not after. A tower that lifts off the plate tells you nothing about temperature, and adhesion failures and adhesion successes are both dangerous — too little and the print pops off, too much and PETG takes your build sheet coating with it.
Phase 2 — Thermalabout 15 minper filament
How to do it
START WITH YOUR PLATE, not the filament. Whoever made the build plate publishes a temperature range for it, usually printed on the packaging or on their site. That figure beats any table, including this app's — the plate is what the plastic actually touches.
Tell the app which plates you own, in Setup. It then holds a separate bed temperature per plate for each spool, because one number per filament cannot be right for two different surfaces.
Wash the sheet with dish soap and warm water. Isopropyl alone redistributes oils rather than removing them, and fingerprints are the most common adhesion failure there is.
Decide whether this pairing wants an adhesive, and know WHY — the Materials page gives the answer for your plate and filament together.
Let the plate cool before removing parts. Most sheets release on their own, and levering at a warm plate is how coatings get damaged.
How to read the result
The part holds through the print and releases cleanly once the plate cools.
What you need
Dish soap and warm water
A PVA glue stick — the ordinary school sort. This is the usual answer for both jobs below.
Optional: hairspray, for glass. Cheap and effective; get it on the plate, not the machine.
Optional: a purpose-made adhesion spray or liquid. Works, but does nothing a glue stick cannot for most materials.
NOT the same job: glue for ADHESION makes a print stick to a surface that would otherwise let go — PLA on a cool plate, anything on bare glass. Glue as a RELEASE agent stops a print bonding permanently to a surface that grips too well — PETG or TPU on smooth PEI, nylon on bare PEI. Same stick, opposite purpose.