Print quality and filament moisture
I've read up on the effects of moisture on filament, and have been making a point of packing each spool away in a sealed bag with fresh desiccant. For the last 9 months, I've had no real issues. Right before Christmas, I purchased some FormFutura rPET (recycled PETG) that really brought the point home. I've printed with it a bit in the last week, took a break, then returned again to print some big functional parts using a 1.0mm nozzle at 0.48mm layer height. I was really disappointed in the results. Fortunately, I received a PrintDry for Christmas (timely), and tossed the spool in for a couple of hours, then re-mounted it and tried the same gcode again. I was quite surprised at the difference:
The dried result is at the top, the original on the bottom. This filament is apparently a lot more thirsty than any I've tried before. I knew drying filament and keeping it dry was important, but I'd never experienced this quick of a degradation. Just a note to anybody suddenly experiencing problems, consider drying your spool out and trying again!
Re: Print quality and filament moisture
I've also noticed that getting a good first layer becomes increasingly difficult with PETG that has been exposed. I purposely left some outside for a while to see the effects. It was close to impossible to get a decent first layer without blobs and missing bits.
Some brands seem to be more prone however.
Re: Print quality and filament moisture
Some brands seem to be more prone however.
And with recycled material, it'll probably vary from roll to roll.
I have two rolls of Spectrum PETG filament (one clear and one yellow). They have been out in the open for over a year, as they didn't come in re-sealable bags, and I don't have any spares around. But they still print perfectly to this day.
Now, my nylon and PC rolls.... That is another story (damn, they are thirsty) 
Re: Print quality and filament moisture
Did you weigh the roll before and after drying?
I wrung 6 grams out of a roll of TPU!
Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
Re: Print quality and filament moisture
Did you weigh the roll before and after drying?
I wrung 6 grams out of a roll of TPU!
No, sadly. I really didn't expect it to work as well as it did so was pretty cavalier about the whole thing.
Re: Print quality and filament moisture
So was I.... I dried the filament and then didn't use it...
Should have done a before and after print too
Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
Re: Print quality and filament moisture
+1 for my PrintDry as well. It's super convenient for prepping rolls. Even more, it lets you deploy silica drying packs with impunity. My PrintDry regenerates those at the same time it is processing spools. Originally, I was put off by the price and was going to build my own with a food dehydrator, but once I got the PrintDry, it was pretty evident that my time would not have been better spent fashioning my own spool dispensing chamber levels. I don't even think about its cost any more - it has easily earned its keep.
Definitely check PrintDry actual temperature with a heat probe. The dial on mine is 5 to 10 C off. I use this Signstek ($15 from Amazon) https://www.amazon.com/gp/product/B00FFYEPVQ . Stuck one probe into each level of the PrintDry and gradually turned up the temperature while checking every 15 minutes to see the actual temp. The lower chamber is naturally hotter. THAT is the one to track to avoid overtemp.
Once I found my "calibrated" set points for PETG and PLA, I marked the position on the PrintDry dial. Although, I recheck occasionally with the thermocouples, the marked settings remain OK.
Keeping my active spool dry could be done by directly feeding out the PrintDry, but instead I simply seal the active spool with an upside down, plastic hanging file box ($20 https://www.amazon.com/gp/product/B002JLTMR0 ). I include several indicator drying packs with the spool. Foam weather stripping seals the bottom of the bin. Allows a couple print days before a spool needs to be reprocessed.
Here it is atop my LACK enclosure.
Re: Print quality and filament moisture
Or (with a small amount of effort) you can convert a food dehydrator.
Re: Print quality and filament moisture
Or (with a small amount of effort) you can convert a food dehydrator.
You can, absolutely. I considered doing so, but then the PrintDry was at a reasonable gift cost and I really didn't need anything else.
When I looked into it, a decent food dehydrator solution came to about $60 plus print & assembly time. The PrintDry does come with the hardware (lazy Susan rollers, grommets) for feeding fitted, and some other nice goodies (2 tier tray, desiccant, spools) you'd miss out on. Maybe not an additional $60 worth of parts, but it definitely is a simple ready-to-go solution.