I was looking at buying a camera dry cabinet to store extra filament while not in use. I saw in an article on all3dp that talked about using these cabinets.
The one that I’m looking at can regulate humidity from 25 to 60%. In the technical data for bambu filament it says that the relative humidity needs to be <20%.
Would the cabinet that I was looking at not be good?
Don’t bother. It’s not really needed, unless you are printing a lot of material sensitive to moisture, like nylon.
Common filaments, like PLA or PETG absorb very little moisture, therefore you can print them without loss of quality even when stored in 50-60% humidity environment for months.
If you want to be extra sure, that moisture in old filament is not going to cause printing defects, you can put it into oven or food dehydrator for a few hours on 50 degrees Celsius/122 Fahrenheit for a few hours before printing.
Thanks for the advise. I’ll save my money.
I’ve been storing up to 2 rolls with a couple desiccant packs in 2 gal “freezer bags” (zip lock). Has been working very well over the past year as a very inexpensive and flexible storage option. I have two “print boxes” with built-in rechargeable desiccant packs that I move rolls two that are being used on current projects and feed directly from there to the printer.
Get moisture barrier bags like this https://www.digikey.com/en/products/detail/desco/13962/4500580?s=N4IgTCBcDaKHAEBGAzATgGxjiAugXyA and put filament inside with a mid size pouch of desiccant. Then roll an open end of the bag like 5 times and fix with clothes peg or foldback clip. Way cheaper and works better than any dry box and will keep filament dry for years.
I recently finished a couple rolls of pla that had been sitting in the bottom drawer of the toolbox that is my printer stand since 2016. No special storage, not even a ziplock for one roll. Print came out fine.
That said, I do have a eibos dryer for nylon and other fussy filaments. I use it if I’ve left a spool out too long without repacking it in a vacuum bag.
On your original question, in case anyone else is looking, you want a cabinet that can do under 10% RH or it’s not really worth having for filament.
I don’t agree with the view that some have about filament being left in high humidity environments and being “fine” with no loss of quality though.
PETG does see an increase in blobbing and stringing when it’s more moist, and as someone who prints almost exclusively functional parts, 99% of my filament is in dry-boxes, and gets printed from dry-boxes.
I wouldn’t buy an active dry cabinet for it, but it’s more critical to store it dry if you’re not printing a lot of a more sensitive filament as a) repeated drying takes additional energy, and b) repeated hot-cold can damage the filament itself. You don’t want to keep drying the same roll over and over, and having to dry it before use in a project is a real pain - it really messes up the process when you’ve got a nice fast machine, but you’ve got to wait 12h for your part anyway as your engineering filament needs to dry for 8h at 70C…
I just have some big airtight plastic boxes (70l) with a big mesh bag filled with desiccant, and everything that’s open that’s not in use goes in there. Silica gel will bring the RH down to approx 11%.
Here is a “Husky tool” dry box with a filament tube connected to Bambu.
Lid hinges open to a large spool and one pound of desiccant.
-Uman
That’s very high. Either your boxes pass a lot of moisture (non metallized plastics pass moisture), or humidity meter shows incorrect figure. Moisture barrier bags with silica gel pouch easily keep <5% RH which is the minimum humidity indicator cards I use can show.
Sadly those indicator cards just lie to you.
Well dried silica gel alone can theoretically get the relative humidity down to below 10%, but you need an insane amount of silica gel to get there and decent air movement through your desiccant, and in practise I’ve never seen anyone (with accurate hygrometers, not indicator cards) get below 10% for a filament dry-box. Also, my boxes are 70l with no forced airflow. Despite about 1kg of well dried silica gel, I’m unlikely to see below 10% as I do occasionally open the box.
They’re perfectly sealed, but the physics just dictates that it’s very difficult to get very low RH levels in such a setup.
Btw. is there even someone selling dry box with properties mentioned in original post, that is with regulation of humidity from 25 to 60%? I couldn’t find any. All dryboxes I’ve found use either heat or dessicant to keep filament dry, but none of them can regulate humidity inside the box.
Why would they lie to me? I get them together with electronic components from serious distribuitors. They are used for electronic component storage compliance, rather strict stuff which complies with standards. Air tight does not mean it does not get penetrated by water vapors, regular plastics pass that easily. That’s why moisture barrier bags have inner aluminum foil layer.
