Detecting bad filament (and how to find good filament)
After a lot of troubleshooting (and help from many members of this forum - THANK YOU!), what I thought was an issue with my printer turned out to be bad filament. I was having a lot of issues with prints making it 20-30 minutes into a print, then starting to fail. I thought I might have an extruder issue, etc. but found out that cleaning the nozzle would allow me to print again - but only for 20-30 minutes.
Long story short I realized I had also switched from the filament that came with the printer to some I bought at my local Fry's Electronics. Cleaning the nozzle again and going back to the original filament I discovered the problem went away. I switched back to the Fry's stuff and the problem came back. (Note - this was all with PLA, I haven't tried any other materials yet).
So with that discovery finally resolved, my question is:
How can I tell if filament is any good before going through all the steps I dealt with above. And as a follow up - are there particular brands that are known to be good or bad I should look out for?
Re: Detecting bad filament (and how to find good filament)
So, the big question is what is wrong with the bad filament.
1) The temperature settings are different enough to cause a problem.
2) Filament is more prone to clogging (can that be fixed with settings).
3) The diameter tolerances are not good enough.
To address these, you may want to:
1) Print a temperature calibration tower (search thingiverse) and see if the Fry's filament is more temperature sensitive.
2) Settings that can affect clogging: Too hot. Too much retraction. Too fast a retraction.
3) Use a caliper to measure the filament diameter at various places. If it varies too much, stop using that brand.
Because your problem kicks in 20+ minutes into a print, I feel it might be heat dependent, especially making sure that the heat break remains cool enough. Are you in an enclosure? If the ambient temp gets up to about 40C in an enclosure, no amount of cooling fan across the heat break cooling fins will prevent the filament from softening in the heartbreak (where is SHOULD be solid). Adding some ventilation to the enclosure should fix that. It might be that this problem simply happens a bit sooner in one brand of Filament than the other, but the problem is there.
All that said, I really like the Hatchbox PLA which you can get directly from Hatchbox in CA or off of Amazon. The colors are good, the consistency is good and it prints well, and it is at a good price.
Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage or loss. If you solve your problem, please post the solution…
Re: Detecting bad filament (and how to find good filament)
Thanks - I'll try some of those ideas. The problem is clogging (very noticeable when I clean the nozzle and because the filament is orange, it's pretty obvious when there is extra goop). I also noticed remnants on the extruder gear - so it appears it was trying too hard to push filament into the nozzle and stripping off pieces of plastic).
I've printed 8+hour items with the filament that shipped with the printer, so I'm reasonably confident my overall settings are ok - just need to either get better filament or tweak it to match the filament I have. (I honestly never considered that the filament could be ok and just require some different settings, so that's great input).
BTW - the printer is not in an enclosure and I've tried additional fans, but it didn't make a difference.
I'm going to experiment with the temperature settings and if none of the other ideas work, just try the Hatchbox PLA.
(As a side - the brand I'm having the issues with is Shaxon. The listed specs are temp 180-240C, density 1.25, tolerance +- 0.03-0.05 mm)