Pre-ramble
This is a new thing – Short take – that I will do from time to time. Short takes will be in-depth discussions on master-level topics of Molecular Biology and Quantum Mechanics. No, just kidding they will be short single topic posts. Unless you’re interested in the latter, let me know in the comments.
Included in this post are links to items on Amazon. As an Amazon Associate, I earn from qualifying purchases.
Keeping PETG dry
Today a quart of desiccant I ordered last week arrived. I don’t have a mold or moisture problem, I got it as part of the care and feeding of my PETG filament. PETG is hygroscopic, which means it absorbs moisture. Since PETG is extruded at a relatively high temperature, I use 235C for most of my prints, moisture in the filament can lead to all kinds of bad adhesion and artifacts in the print if there’s enough moisture to effectively boil out. For the best print quality, it’s best to keep PETG, and this applies to ABS filament as well, as dry as possible.
Until now I kept my 2 spools in gallon size zip-lock bags with an itty bitty desiccant packet when they were not on the machine. I haven’t been 3D printing that long so I haven’t personally seen the effect of “wet” filament but there are a lot of YouTube videos about it. And there are almost as many with instructions on making containers for holding the filament in a moisture-free environment.
I don’t know how much filament I may eventually have lying around, I guess it depends on how much printing I do and whether I go down the “path to castration“. So to start I’m keeping it simple, just a container with the desiccant in the bottom where I keep the filament when I’m not printing. I had an unused plastic container I can get the 2 spools in with a locking lid. I may be able to get 3, or 4 spools into it if I don’t include the Master Spool. I’ll still have to open it to remove the filament to print, but this is a little less of a hassle than the plastic bags and with more desiccant than the puny bags I was using. The lid is latched on each end, so the lids are pretty secure but it doesn’t have a good seal so I got some weather stripping tape and put it around the outside of the container.
The desiccant I got is orange and turns blue as it absorbs moisture. When it’s heading in that direction I can swap it out for some dry (orange) desiccant and dry the saturated beads in the oven or microwave. Or so says the instructions on the bottle.
The box is the perfect width but it’s just too short to put the spools on a holder upright so I could eventually feed the filament out the side while keeping the whole thing mostly sealed. I’ll start looking for one with similar dimensions but taller if I think feeding from the box is something I’ll want to do.
Oooo, I just had an idea for a cool Arduino project. A set up to monitor the temp and humidity of the box and if it gets too high have it call 911 every 5 minutes until it’s acknowledged with a recorded message, “Emergency, Marks PEGT storage box humidity has exceeded <TBD>%. Send emergency crews immediately to <insert my address here> with extra desiccant and make all efforts to let Mark know now!”. I’m sure the police would track me down as quickly as possible if they found out the humidity in my PETG filament storage box was high.
Return from interrupt…
Mini-review – SUNLU filament
As is usually the case when I’m going to buy something that costs more than a couple of dollars I spent way more time researching than is probably (ok honesty is the best policy) actually necessary. I spent many hours reading about filament, watching YouTube videos about filament, checking reviews for different brands of filament, and finally, an unreasonable amount of time checking eBay, Amazon, and other sites looking at what was available. After all that, and changing my mind more times than a modern CPU switches context in a minute, I settled on filament from SUNLU because they sold filament in 2 packs (I got 1 black and 1 orange 1KG spools) and they used something they call “Master Spool”.
Master Spool is a spool that separates so you swap out spools of filament. It makes it possible to buy just the filament and not spools. I don’t like waste, the piles of newspapers and bags of crushed aluminum cans in the back yard I intend to someday take to recycling attest to my desire to not throw things away. If I cut my spool count in 1/2 that’s a win for me. I got the SUNLU Filament 1.75mm PETG 3D Printer Filament PETG MasterSpool Filament 2KG PETG Black+Orange but there are many combinations available. And as a little bonus, they come with small velcro straps (the blue things in the picture below) which can come in handy for wrapping up cords or when I have enough stuck together end to end and used as a stylish belt I can stick things to.
I’ve been very happy with the SUNLU filament. I don’t have much alternative reference at this point but I think the quality of my prints has been good and consistent. I don’t get a lot of blobs, unevenness, or stringing. I’m not sure if it’s the printer, the filament, or both.
I’d recommend SUNLU if anyone asked and as I already mentioned I like the master spool idea. I’m sure I’ll try some other filaments in the future that only come with their own spool but I’m sure I’ll find something to do with the old spools.
Happy printing!