How to get finger oil off a textured plate
1 The first layer copies your fingerprint
You touch the build plate and the first layer draws that fingerprint in the plastic. The oil kills adhesion. The print will not stick, and it can come off while the nozzle is still moving.
2 Alcohol smears oil into the texture
Wiping with alcohol is the usual fix. On a textured plate it smears that oil through the grooves instead of lifting it. The plate looks wiped. The oil is still there.
3 Warm water and plain dish soap
Take the plate to the sink. Warm water and plain dish soap, not the kind with lotion. Lotion leaves a film that kills the stick the same way the oil does. Scrub with a sponge until the soap gets into the grooves, then rinse and dry.
4 Hold it by the edges
After it is clean, hold the plate by the edges. A fresh fingerprint puts the oil right back on the surface you just washed.
5 The water-film test
Drop water on the plate. If it beads, it is still dirty. If it sheets into a thin film, it is clean. Then print. Do not scale a model just to make it fit the bed.
FAQ
Why does a fingerprint show up in the first layer?
Skin oil sits on the plate. The first layer cannot stick there, so the plastic traces the fingerprint. The part can also let go while the nozzle is still moving.
Does isopropyl clean a textured plate?
It often smears the oil through the grooves instead of lifting it. Wash with warm water and plain dish soap, scrub into the texture, then rinse and dry.
What kind of soap?
Plain dish soap. Skip the kind with lotion. Lotion leaves a film that kills adhesion the same way finger oil does.
How do I know the plate is actually clean?
Drop water on it. Beads mean it is still dirty. A thin sheet of water means it is clean. Then pick the plate up by the edges so you do not oil it again.
Full transcript
You touch the build plate and the first layer draws your fingerprint in the plastic. That oil kills adhesion. The print will not stick, and it can come off the bed while the nozzle is still moving. Wiping it with alcohol is the usual fix. On a textured plate, alcohol can smear that oil through the grooves instead of lifting it. Take the plate to the sink with warm water and plain dish soap, not the kind with lotion. Scrub with a sponge until the soap gets into the grooves, then rinse and dry. Hold the plate by the edges after that. Lotion in the soap leaves a film that kills the stick the same way the oil does. Drop water on it. If it beads, it is still dirty. If it sheets into a thin film, it is clean. Once the print stays on the plate, do not scale a model just to make it fit. Obloid's AI part splitter breaks it into pieces that fit the bed at full size.
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