When I first got my printer set up and tweaked for a roll of inexpensive (Amazon Basics, LOL) PLA, I was pretty darned impressed with the print quality. It had taken some fiddling, but once it was working, wow! It just worked! Hardly any stringing (er, well, after I learned about and made more adjustments in the slicer) and hardly any cleanup work post-print. I was so stoked.
But then I didn't mess with it for a while, and when I did, even though no settings had changed, even tho I let it warm up a-plenty... the exact same prints - an owl or a Benchy - looked like ASS.
That was when I learned that all filaments are hygroscopic. What had changed was that we were now in summer months, and the evap cooler was running, with the coolest, densest, dampest air settling in the basement where the printer is. The consequences of "wet" filament are worse for some materials than for others. Although good old PLA is highly
hygroscopic, it is probably the least sensitive to humidity in terms of effects
on the printing. On the other hand, PLA is one of the easiest to dry
out, and doesn't require a high temp or long time soak to do so.
It was around then I bought a tent (or a friend did; I can't remember who bought which accessory 'cuz right after one dear friend GAVE me a brand new E3V2 as a gift, another dear friend bought me a ton of accessories) -- then I built a circulation fan and tube, and a temperature control box with a PID controller in it. Inside the tent are several "socks" (piece of wife's old pantyhose) filled with silca gel. The controller build is documented in this post.
The tent keeps already-dry filament from getting "wet" but it's not hot enough to dehydrate wet filament, unfortunately. If it were, the electronics of the printer would COOK, killing the printer.
For storage, I've just been keeping unopened reels in their bags, but I've recently learned that over enough time, water vapor can penetrate most of those bags too. Opened reels I've just been resealing with clips and with another small silica gel sock in each bag.
Unfortunately, it now appears I need a filament dryer. Of course the
first thing I thought of was making my own, but when I looked at the
cost of parts and my own time, I'd be spending more money than even a
deluxe commercial unit costs. Which frustrates me because either way it
is far more money than I want to spend. Maybe the prices will drop enough after the holidays. 😒
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Filament Temperature Time (Hours)
PLA 55°C (131°F) > 3
ABS 65°C (149°F) > 3
PETG 65°C (149°F) > 3
Nylon 75°C (167°F) > 12
Desiccants 65°C (149°F) > 3
PVA 45°C (113°F) > 10
TPU/TPE 55°C (131°F) > 4
ASA 65°C (149°F) > 4
PP 55°C (131°F) > 6
HIPS 65°C (149°F) > 4
PC 75°C (167°F) > 6
PEEK 75°C (167°F) > 6
These recommendations are made under the following conditions.:
• ambient humidity: 50% RH
•
ambient temp: 25°C
• for a single 500g filament spool
= trying to make any kind of coherent chart in Blogger is nightmarish =
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Now, there are
compromise solutions, but they don't work very well for me.
One way to dry a roll
of filament is to put it on top of some non-heat-conductive spacers (so the reel isn't in direct contact with the bed) on
top of your printer's print bed, then enclose the reel with a spare cardboard reel box,
then adjust bed to correct drying temp, set a timer on your phone or a kitchen timer, et voila!
Of course, then you can't use the printer... >_<
Another
solution is to buy a food dehydrator cheap, if you can find one on sale
or the thrift store, then 3D print a support spider for the reel (uses three
ball bearings, works like the one in your microwave oven), and 3D print
a housing to keep the hot air in - the trays that come with the
dehydratopr are not worth the trouble to try to make a side wall housing
out of. This seems... okay-ish, to me, but I'm not wild about it. It does have the advantage (most food dehydrators do anyway) of reaching 85C for drying out the more "engineering" filaments.
Now
I had originally had the notion of making a filament dry box to keep
filament dry while in use, it's easy and cheap to make one from a clear
plastic storage tub... but that won't dry out filament that has gotten
"wet". And if I have a dryer, they're already set up to be used while
they dry anyway, so I wouldn't need the separate dry box... but I do need a
dryer of some kind... grump.
This is why I am now pondering this perfect - and expensive - four reel / two oven filament dryer:
The Creality Space Pi X4 has two ovens with independent temperature and timer controls, enabling two different filament types to be dryed at once, and all four reels can be in use if you have four printers or an Automatic Filament Changer.
The latter is something I might tackle some day - there are DIY print-your-own / build-your-own files on the 3D model sites, there are unassembled kits with all the parts bought for you, and of course there are ready to use commercial ones.
So long as you're slicing with Prusa, the use of an AFC should be fairly slick, automatic, and without manual intervention. You declare the colors of the various parts of the model in the slicer and it takes care of the details. (hah! there is always some fiddling to get set up)
So once it's dialed in, color changes mid-print with a single-filament cheap printer like my Ender3 (or any other bed-slinger you might have) suddenly become trivial. No need to drop three thousand simoleons to have a multicolor printer!
Another criteria that narrowed my choices a lot is the need to dehydrate high-temp and high-density filaments like nylons and PEEK. I already have some, and I intend to get others like PC, so a dryer has to be capable of max (about 85ºC should be the highest you ever need) drying temperatures.
hot rodding, in that you really can unbolt one part and then
bolt on another that adds performance, before you even take
apart an engine - new intake manifold, big carb, carb temp
spacer, turbo or maybe a Paxton blower, exhaust headers,
spicier ignition unit, higher flow fuel pump, and so on.
But unlike a chrome air cleaner or vortex inducers, most of the 3D printing hacks actually do improve your printing, ie; they are not snake oil. :) And it's FUN.
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