I am using PLA+ purple with a temp range of 205-225. I am using a temp of 219 and a hot bed temp of 50. The print will get in for about 60 minutes and anything after that will not stick. Sometimes I get a clump on the nozzle and that knocks things off.
Ive tried things with more than one starting point, think of legs, and those will only stick 3 legs until the 2nd or third layer.
In all cases so far the only thing I get to stick is the Benchy test print. The Moai, that is another item that I posted in another thread.
Hairspray? Aqua-net seems to be tacky enough. I've yet to print anything larger than the benchy but hadn't been concerned since these textured build plates tend to stick pretty good. I'd also suggest bumping up your first layer bed temp. I usually start my PLA at 60 and then let it back off to 50 over the first few layers. Depending on the model you can put a brim on which will help with adhesion.
I have the brim, but the excess seems to knock it off. Also after 60 minutes, nothing is going to help if the print dislocates
Check your print surface is clean before printing.
Also check your z-offset and adjust incrementally (0.1mm), you may simply not be printing close enough to the surface to get a good first layer.
Agree on all 3 points
Clean the bed with isopropyl alcohol (glasses lens cleaning wipes or injection swabs).
Adjust your Z offset (nozzle should just grip 2 sheets of paper).
I use hairspray for PETG but have had good results with Pritt Stick when printing PLA (before I completely gave up on PLA as it has no benefits over PETG!)
I have it grip a folded sheet of paper. I will clean it again. I am also wanting to try blue tape.
It is just frustrating to print for 60 minutes and then watch a "glob" knock the print over.
I've used blue tape before and it worked fine but was happier with Pritt Stick.
If you are getting a "glob" on you nozzle tip, you may need to tighten the nozzle.