Has anyone had issues with pla sticking to some areas and not others? When doing prints with large surface bonded areas I’m getting spots and stripes that don’t stick and drag around and make big balls of crap.
The spots are very small sometimes a 1/4" and all around it things stick so that makes me think its not bed leveling. My thought is its inconsistent surface texture/coating in my painters tape. Which is weird because this roll has been printing incredibly well until now.
I tried wiping the surface down with acetone and that helped some but not 100%. One other thought is I might be running too hot. I ran 220-235c in my e3d hotend.
One trick I’ve heard a lot of people tell of is hairspray. I can’t bring myself to put a flammable compound near my 230 C nozzle, but everyone says it works.
Are the spots it’s not sticking places you could have touched with your fingers? I have trouble touching my build platform. It’s sometimes difficult to pick the skin oils up instead of just smear them around.
Or could it be places that you have printed on a lot in the same spot? I think the ‘stick’ wears off the tape after time - I suspect the treatment applied to the tape is pulled up a little at a time every time you pull a finished part.
Hair spray is amazing with abs but I wasn’t sure about it with pla. It’s worth a try though.
And for the record once it’s dry hair spray is perfectly safe.
I replaced my perspex build plate with a glass one because I was printing without tape, and I think every print was taking an infinitesimal amount of the plate with it as I removed it.
Although PLA varies with colour, I think you are at the high end of the range. I have found that a little Z-offset to squeeze the first layer of PLA down onto the tape/surface worked for me.
How do you change that Z offset for just the first layer? I have a Replicator 2, and I’ve basically resigned myself to listening to the machine rumble as the nozzle scrapes over the raft layers. It stops when the real object starts, but while its printing the raft, I can hear the nozzle brush every single extruded row of plastic in its way.
@Michael_Vaughan As I don’t have a Rep 2 not sure. I do it in Slic3r under the printer tab. There you can spec a + or - ve value to your Z for a given machine config.
I don’t ‘raft’ but it seems that slight interference with it on the first layer would be a good thing to help bond it …
The first couple of times it freaked me out, because I just had my new toy and it was making terrible noises, but now I take it as a good sign on the raft. Normally I try to print without a raft if I can get away with it, though. I like the smoother finish I get. I only print with a raft when an object needs some pretty extensive support and I don’t trust the support material to stick.
wipe the blue tape with a little isopropyl alcohol before you print.
I’ve been changing tape between prints so I don’t think it’s worn out. I’ll try isopropyl tonight. Does any one know if printing too hot will effect adhesion?
I had similar issue - now I use hairspray and after use I wipe once or twice with rubbing alcohol(70%) and that makes left over hairspray sticky again, very sticky.
Once a while I add new layer of hairspray on glass.
PLA bed temp I put 45C but hairspray was working on not heated bed
I go 200C on the high end for PLA. I’d also try slowing down the first layer. +1 for acetone, every print.
I had a similar issue, and I tried adjusting various parameters while the first layer was being filled in. Nothing helped, except raising the carriage by ~0.1 mm by rotating the Z lead screws manually. I get this problem with just one kind of PLA. Looks like this plastic is stickier and thicker. The first layer is overextruded for better adhesion, and eventually it sticks to the nozzle and fouls it. Increasing the initial bed gap a bit seems to help.