Flashforge filament not sticking

[Ward]

For a brand new printer with a brand new print bed assuming nothing is physically broken, the problem has to be (with >90% probability) that the bed isn't close enough to the nozzle. It's a little unfortunate that we call it "level build plate". Technically what we're doing is "tramming" that is making sure the bed is parallel to the print head motion.

But for beginners printing small parts at the center of the bed, even more important than "level" is how far. Because the code isn't big enough to notice much tilt in the bed, it's more important how far away the bed is. I think that's why beginners get confused by the "leveling" terminology and say things like "the bed is level".

Yes, it may be "level" but it is "level" too far away. When the printer commands Z=0.2mm for that first layer, it needs to be pretty close to 0.2mm because the extrusion has to hit the bed to stick.

I think that sample part was sliced with ReplicatorG which assumes that you are actually at 0.25mm away when z=0.2mm which provides for a 0.05mm piece of paper. Many slicers however assume that it matches precisely. It should be ok +/- 0.5mm it's just the first layer will be either underextruded (adjacent lines won't stick to each other) or over extruded (elephant foot). Beyond that, it's likely to have problems not sticking either because the head isn't squishing it much and/or it's running into the over extrusions and cleaning the print up into a ball on the nozzle.

This seems like a really good and informative post. I may be wrong, but I think he's right.

[warkmal]

Maybe. But if you're printing with ABS and the part has relatively small contact area, you either need a raft or a brim. ABS wants to pop off the plate when it shrinks so it needs enough stuck to the plate to hold it there until you're done.