Your first layer won't stick? Start here.
A print that won't grip the bed — or pops loose halfway and turns into a plastic bird's nest — is the single most common beginner failure. The good news: it's almost never something broken.
The short answer
Clean the plate — do this first
Your fingers leave an invisible film of oil on the build plate, and plastic will not stick to grease. This is the most common cause and the easiest fix, yet it's the one everyone skips because the plate looks clean.
Wash it with warm water and a drop of dish soap, scrub with your fingers, rinse, and dry with a clean paper towel — then handle it by the edges only. A huge share of "my printer is broken" posts are solved by a two-minute wash.
Set the nozzle height (Z offset)
The first layer has to be pressed slightly into the plate to grip. If the nozzle sits too high, the plastic lays down as loose round strands that peel up as they cool. That gap is the Z offset.
Set it live: start a print, watch the first layer, and lower the offset in small steps until the lines look flattened and fused, with no gaps between them. The diagram below shows exactly what to look for.
Slow down and warm up the first layer
The first layer needs time and heat to bond. Set the first-layer speed slow — around 20 mm/s — even if the rest of the print runs fast; it costs a few seconds and dramatically improves grip. Check bed temperature too: roughly 60 °C for PLA, 70–80 °C for PETG. If your printer has an auto bed-levelling step, run it — it maps the small highs and lows so the first layer stays even everywhere.
How to read your first layer
Once a print starts, the first layer tells you everything. Compare yours to these three:
Nozzle too high
Round, separate strands with gaps. Won't grip — lower the Z offset.
Just right
Flattened, touching, smooth on top. This is the target — leave it alone.
Nozzle too low
Thin, translucent, ridged. Scrapes the plate — raise the Z offset a touch.
On a Bambu Lab
Still lifting? Add grip.
If the basics are right and a stubborn part still lets go, help it along. Abrim — a flat skirt printed around the base — adds surface area and peels off cleanly afterwards; it's the first thing to try. A swipe ofglue stick gives smooth PEI extra tack (and with PETG it protects the plate from being torn up — see PLA vs PETG). Araft is the last resort for tiny footprints, at the cost of wasted plastic and a rougher bottom.
If it starts fine and lifts later
That's a different problem — the corners are curling up as the plastic cools and shrinks. That's warping, and it has its own fixes. Seewhy your print is warping.
Common questions
Why is my 3D print not sticking to the bed?
Almost always one of three things: the plate is dirty (finger grease alone is enough), the nozzle is too far from the bed on the first layer, or the first layer is printing too fast or too cool to squish down. Clean the plate with dish soap and water first — it's the fix people skip and the one that works most often.
How do I clean my print bed properly?
Warm water and a drop of dish soap, scrubbed with your fingers, then dried with a clean paper towel. That removes the invisible oil your hands leave behind, which is what most prints fail to stick to. Isopropyl alcohol wipes help between washes but don't cut grease as well as soap and water. Handle the plate by the edges afterwards.
What is Z offset and how do I set it?
Z offset is the gap between the nozzle and the bed on the very first layer. Too high and the plastic can't press down enough to grip; too low and it smears or clogs. Set it live: start a print, watch the first layer, and nudge the offset down in small steps until the lines look slightly squished and fused with no gaps. A good first layer looks like flattened, touching ribbon — not round spaghetti.
Should I use a raft, brim, or glue stick?
Try a brim first — a flat skirt printed around the base that adds grip and peels off afterwards, costing almost no plastic or time. Glue stick helps on smooth PEI and is essential to protect the plate when printing PETG. Rafts (a full printed platform under the model) are a last resort for small-footprint or badly warping parts — they waste material and can mar the bottom surface.