Baking Old Filament May Reduce Water Content

Good Morning from my Robotics Lab! This is Shadow_8472 and today, I am getting back into 3D printing, but I doubt it’s going to be pretty. Let’s get started!

Inspection of Equipment and Materials

My 3D printer is in used condition. The print bed is scratched and one of the two Z-axis rods got bent at around the same time. My filaments are old and brittle. I can’t even use the slicer it came with anymore because it’s both outdated and made exclusively for Windows. I’d rather just start over with a standard one designed to be user-serviceable. But that’s not an option at the moment.

I should learn about what I already have and work from there. There’s not much I can do about the scratch unless the original replacement pad shows up or unless I’m willing to fill it in/cover it up somehow. As much as I’d like to replace the Z-axis rod, a suitable replacement proved elusive for reasons discussed above; besides, the tweak doesn’t look that bad – the top of the rod only moves back and forth a little when the print print head is moving vertically and is down low. Alternate slicers exist. Long story short, I may as well give this printer one last chance before giving up on it completely.

Filament Reclamation

I have two PLA filaments I’m considering today: my original, red one and an opaque white one I got later and hardly ever used. Red used to just work. White felt different from its day 1 and never printed nicely. After a couple years of absorbing moisture from the air, they’re both as stiff as spaghetti. I even bent one piece of White until its middle piece snapped out from between the ends.

Besides causing stiffening, absorbed water evaporates when exposed to heat, causing problems such as the ones I experienced last time I tried printing. Water from within the filament forms steam, and it’s the steam that causes mysterious jams that seemingly go away come time for diagnostics.

A number of places have listed methods for drying out filament: bake it. Just be aware of the material’s glass transition phase where it goes from resembling a wire to resembling a more squishy rubber. The whole spool will fuse and you’re reclamation efforts will be for none. For PLA, that transition is somewhere around 140 degrees Fahrenheit.

To be safe, I elected to aim for 100-120 degrees F. My stove at home doesn’t hold its temperature that low. We put a bowel of water in overnight with a rising loaf of bread and it tested way cooler than needed. We tried our old toaster oven and tested at 125 F – close, but as I only had one shot to fix what I have, I didn’t want to risk it.

Specialized devices exist to dry out filaments. I was able to approximate one by modifying a food dehydrator operating at 125 F. My final design involved a rheostat from my father’s soldering iron to adjust the otherwise fixed temperature, some Duplos (a Lego-like block aimed at younger ages we’ve had laying around since I was little) to hold up the lid, and a tall, plastic film from my mother’s cake supplies to extend the tray. Without a thermostat, I monitored the temperature myself with a digital cooking thermometer we got for my sister’s bread making.

Both Red and White were dried overnight. White still felt stiff, so I left it in for several hours more. The temperature was difficult to keep constant. I left the contraption in a small room, and the room warms up and I have to turn the power down. If I had known how to easily, I would have built a thermostat capable of operating in those ranges. In retrospect, it would have been better to just leave it in the toaster oven on warm and not worry about it.

Side Project

I was able to get Vaultwarden running by forwarding the incoming traffic to the container’s port 80 instead of 443. However, this is still sub-optimal. I have my ability to manage passwords between devices back, and that feels sooo good after months of downtime, but I’ve been strongly encouraged to use a reverse proxy. This week, I looked into NGINX, and I believe that will be a focus some time in the coming weeks.

Takeaway

The path to my improvised filament dehydrator was a little longer than going right there. My early approach was At first, I figured I’d want to build something with a couple appliance bulbs like what the oven uses. The food dehydrator I eventually used as a base only has an on-off switch, so to lower its steady state temperature, I used some short Duplo stilts to raise a lower level to let ambient air in. I kept them for my production run, though if I have to run it again in the future, I’ll leave the sides closed and turn the power down lower on the rheostat.

Final Question

What would you tell someone who is ready to know more about 3D printing than: use slicer, level bed, load filament, press start?

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