So I'm having more problems,

So I’m having more problems, I have my heated bed working after a year of having no extra thermistor, and some new PLA which I’m told is RepRap-Walmart(RepRaper) filament resold through Voxel Factory.

Everything is working from a hardware standpoint, however my filament is not adhering to the HBP, and when it does it isn’t stuck in place for very long. I’ve tried lowering the print speed so that it will adhere better, but to no avail. I know that it isn’t the tape on my bed being unclean, as it is a brand new coating.

Any help/insights would be appreciated.

Oh and the extruder is set to 200, with HBP set to 55, and I’ve tried adjusting the bed up and down to see if it helped at all with no result.

Have you tried higher temps on the bed?

@Jonathan_Buford yes, it hasn’t changed anything as far as I can tell. I tried 60 and 65, neither did anything. The frustrating thing is that I was printing with a bit of scrap ABS a week ago and it was printing near perfect. I ripped up the tape when I received the PLA as I had heard that printing with ABS and then PLA without cleaning can end badly.

Yep, that was my next question, hmm. I had a similar problem before, but it went away after printing a few full sized bases at very high temp. Not recommending that process, but I can imagine what you are seeing. Have you tried printing directly on your bed?

on the pcb?

or just the glass?

Yeah, glass or similar. Have you measured what temp your bed is actually getting to on the surface, or if there are hot/cold spots? I’ve noticed that you can get great surfacing with PLA, but terrible adhesion if the printing surface has any contamination that it doesn’t like. If you are printing on tape, is there perhaps some residue of the adhesive you need to take off with solvent?

I Haven’t checked yet, I presume I would need a handheld infrared thermometer or something like that? I’m not sure if it’s contamination, though I have printed on this tape before so I don’t believe that what ever contaminants are on it cause problems with my adhesion. I’ve actually moved the location of the print to another spot on the bed and it is working right now, maybe it is a height problem.

Better to use a probe, handheld IR will give different readings depending on the surface finish, so is not accurate. A cooking thermometer or a thermocouple would be better.

Ah yeah, that would be another potential. Cool. I would check if the bed is level and also if it is flat. Many heated beds will tend to bow at temp, so be sure to check flatness with something long and flat across the whole bed when it is at temp.

I’ve leveled my bed though the height problem would have been due to a variation in tape layers. I’m still having problems, and the spot where it was printing is no longer working, maybe it is the adhesive residue on the tape?

It could be. Have you tried cleaning with acetone and isopropyl alcohol?

I don’t have any of either currently, I’ll pick some up once I have a bit more money, should have done that last grocery day, college life.

I moved the location again and it’s printing so it’s probably an unclean bed.

I just read that wattered down PVA glue (white glue) works well on tape with PLA prints, I’ll try that tomorrow.
Thanks for all your advice so far @Jonathan_Buford !

No worries. Good luck.

PLA on hot glass. 60ºC

For PLA you don’t need any heat on the bed at all. I use double sided tape on the platen and then put a piece of rough construction paper and it works perfectly every time. You need to make sure your extruder is really close to the platform for the first layer so it really flattens the material to get it to stick better. I like this method better than the blue tape because that stuff gets expensive and this one is easy to replace after about 20 prints. Good luck!

Try using any painters’ tape (though it seems like MakerBot is kind of endorsing the 3M variety of blue tapes) on your build platform and it should work ok. You can also try to sand the tape lightly with med grit sandpaper to get the PLA prints to stick to it better, but we’ve tried just “scratching” the surface with our scrapping tool so whatever works, I guess…

Print temperature wise, we normally use the 230C default but since we’re over in hot, humid Singapore, your mileage may vary from ours.