1st layer issues

Hey guys, I've been printing for about 6 months now, and I just recently got some new filament from a supplier I haven't bought from before. I switched over from the red colored 3mm PLA I was finishing off part way through a print to this new "natural" colored 3mm PLA, and then resumed my print. Aside from a minor offset in the resulting layers the print turned out ok, the new filament worked as I expected it to.

After that print though I haven't been able to get a new print started, I'll get my hot end up to temperature, do some test extrusions that succeed, and then start the print. Sadly though, after the 30 second pre-print delay/wait period Pronterface has, my extrusion just fails before the first layer can even be laid down. I'll then pause the print and remove my feed system's bearing that holds the filament against the teeth that force it down into the hot end, and will be unable to force the filament down farther. Then I pull the filament up and find that a good portion of the bottom of the filament has been deformed.

This is the first time I've experienced this, but I'm thinking perhaps the hot end is too hot and is causing the area just above the entrance to the hot end to deform and then that in turn is causing a blockage. I have my hot end set to 185C, what temp would you guys recommend I set my hot end to? Also, is it reasonable to assume that maybe because of a lack of coloring the "natural" color PLA should be set to a generally lower temp, to compensate for its less impeded heat distribution?

Thanks in advance guys!

I've never dealt with nautral PLA, but different filaments needs different temperatures. The problem you describe and conclusion you reach (i.e. too hot) sound completely plausible to me. Find the lowest temperature at which you can extrude filament at a sufficient rate, and try a print with that. And since different people will have different hot ends and different conductivities to different thermistors within different ambient temperatures, you're best off finding that temperature on your own.

Let us know how it works out!

I've tried a few different PLA sources and definately had more problems with the "cheap" stuff. I normally print at 185 - 195C but have gone up to 210C for the cheap filament. I wouldn't think 185C would be too hot to cause a problem with your hotend but what hotend do you have? The cheap PLA could have air bubbles or other debris in it, or it could be inconsistent diameter which can cause jamming. If you have any digital calipers try checking the diameter at several locations along the filament.

My biggest issue with cheap PLA is getting it to stick to the bed.

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