RE: eDry Cabinet (testing and thoughts)
Here are my notes from the test:
- PLA is quick and easy to dry but will get "damp" in as little as 7 Hours
- PETG takes longer to dry but will get "damp" in as little as a 1 Daye
- PA-CF is much harder to dry (takes days) and gets "damp" in as little as 2 hours
- Food Dehydrator at 50c will dry down to around 10%
- Food Dehydrator at 70c will dry down to 0% and is much quicker (but this temp is deemed too high for PLA and PETG as it is above their Glass Transition Temp)
- Vacuum will dry down to around 0.10%
- Freezer Bag will dry down to around 0.17%
- Dry Cab (0%RH) will dry down to 0%
Store and Print filaments in as low a RH environment as possible (eg Dry Box for storage and print from a Dehydrator)
Filament moisture content goes up and down with RH
RE: eDry Cabinet (testing and thoughts)
From what I have read, these cabinets will NOT dry wet filament, or it will take VERY LONG. So use heat, then after it is dry, but it in the cabinet. You could try adding a fan to the cabinets to speed the process. They don't really have one.
The cabinets will dry "wet", it's just slower than baking (which varies by filament)
I'd don't think there is any point adding a fan. They use a molecular sieve and it's fan runs till the air inside the cabinet reaches it's RH set point. As the filament loses moisture to the air and the RH rises the fan kick back on.
If you want "quicker" results I'd say use the dehydrator first, then pop it into the cabinet.
RE: eDry Cabinet (testing and thoughts)
RE: eDry Cabinet (testing and thoughts)
@jmone thank you for sharing the test results! The dry cab has it's place, but it looks like the dehydrator kills it for the quickest results. Did your test use the modified food dehydrator you print from or some other dehydrator? Can you post the make / model?
RE: eDry Cabinet (testing and thoughts)
Yes it does kill it for speed for that initial drying, but it also stores them dry and ready to print without further mucking around. This is the setup I use. The only mods I did was drill holes to pass a PTFE tube directly to the MMU2 (got rid of the stupid buffer) and added a tile from the hardware store as a base. I put the filament spools on those printable rollers. Works great and is cheap as.
RE: eDry Cabinet (testing and thoughts)
sorry, I should have said the PTFE tubes from the don't go directly to the printer, they are seperate tubes that I thread the filament though, so when it retracts the two tubes separate.
RE: eDry Cabinet (testing and thoughts)
@jmone thanks for posting the pic! Great idea! The description of the Sunbeam Lab Dehydrator says the unit s/ only stay on for 19.5 hrs straight, then cool it down for 2 hours before re-running it. Are you restarting it periodically or did you rig it up to stay on all the time?
RE: eDry Cabinet (testing and thoughts)
Ahhh, I never read the instructions! Since I have dry filament, I just set the timer to be at least what the print time is (and 19.5 hours is more than enough for most prints). When I wanted it to go longer, I would just increase the timer back up periodically. I did not notice any issue, but for all I know at some point it may burst into flame and burn your house down. Mine is still just fine after many years.
RE: eDry Cabinet (testing and thoughts)
I will give an update on my Production Automation Corporation (eDry) dry cabinet. It works great. In my house, humidity is about 30-35%. Cabinet humidity 5.6% but I have seen it as low as 4.5%. The cabinet fits 4 spools easily, but will fit 5. The door opening is not large enough to load them in straight, so you usually have to tilt them, which means only 4 spools total. I've been very happy with it, and for $200, its a great deal. I DO dry filament first, then put it in the cabinet. Wet filament causes many more problems then you think.
RE:
As a former employee of Eureka Dry Tech I can assure you eDry and PAC/Eureka are not the same company. They are not even located in the same city.
The desiccants in the Eureka/PAC Dry Boxes will regenerate in time interval cycles.
The FD-3D25 uses a smaller dry unit so it will take longer to dry filaments.
The larger cabinets all uses the same dry unit and is quite capable of removing existing moisture in the filament.
In this video you can see within 24 hours of storing in the cabinet the stringing has begin to reduce. By 72 hours there's essentially no stringing
Here's another video of comparing effects of storing and not storing then returned to the dry cabinet again.
I'd recommend buying a box that would be big enough to hold enough filament that are being actively used for prints.
Vacuum seal any filaments not being used so the storage space can be utilized for other filaments.
From what I have read, these cabinets will NOT dry wet filament, or it will take VERY LONG. So use heat, then after it is dry, but it in the cabinet. You could try adding a fan to the cabinets to speed the process. They don't really have one.
The cabinets will dry "wet", it's just slower than baking (which varies by filament)
I'd don't think there is any point adding a fan. They use a molecular sieve and it's fan runs till the air inside the cabinet reaches it's RH set point. As the filament loses moisture to the air and the RH rises the fan kick back on.
If you want "quicker" results I'd say use the dehydrator first, then pop it into the cabinet.
Absolutely correct. The dry cabinets are generally set it and forget it. The molecular sieves will act as an magnet for any moisture in the chamber and be actively refreshed to maintain a dry enviroment. Adding a fan will not really do much to help dry faster. But increasing the amount of dry units and allow them to regenearte faster cycles in alternating intervals will help.
Give it a day or two before using a freshly opened packaged after being stored in the cabinet and it will print consistently after that as long as it's maintained in the dry cabinet.
RE: eDry Cabinet (testing and thoughts)
So FINALLY got my eDry 90L cabinet from KB3D. This was a "Group Buy" so had to wait about 9 months, but they are also selling them at a higher price. So it holds about 12 1kg spools. It comes with a pole that mounts and holds 5 spools, and I mounted two PVC pipes on the bottom to hold 5 more, and you can fit 2 more in misc locations. One negative is there is no light, so I added a magnetic rechargeable motion light. I will also say the humidity indicator on the cabinet is very inaccurate. I installed a very accurate calibrated SensorPush hygrometer for more accuracy. When set to 3% relative humidity, which the instructions recommend as the minimum, the cabinet can maintain a humidity of around 5% - 10%. I should note, where I live the humidity is 25% - 35% typical. Open the door for a few seconds, and humidity rises to ambient very fast, but drops back within about a hour. Its very quiet, but has a fan that is on sometimes, and it draws 5W - 15W on average.
I also have a smaller cabinet from PAC (Production Automation Corporation) for about $210. It holds about 5 1kg spools. The humidity control is just a simple dial, but in my experience, it keeps the humidity slightly lower than my eDry cabinet, around 4% - 7% humidity. It takes a bit longer to recover from a door opening. No light in this cabinet either.
Both cabinets work well. I use them to store Nylon, PC, and TPU. Most others do OK in our lower humidity.
These cabinets won't dry wet filament, like a container with silica gel generally won't, but are a good way to replace storing filament with silica gel and no need to replace and recharge it. For that reason, I think they are worth the cost.
RE: eDry Cabinet (testing and thoughts)
So the 3D printing company KB3D did what they call a group buy. When I first mentioned it, it was going on. It's now closed. They have done it 3 or 4 times. If a certain number of people commit to buying it, they get the price. If not, everyone gets their money back. The GROUP BUYS are here:
https://kb-3d.com/store/32-kb3d-group-buys
They had to sell 24 of them and they sold 64, so they were pretty popular.
The PAC cabinets are here: https://www.gotopac.com/products/storage/cabinets/dry-storage/3d-printer-filament-cabinets.html
Their biggest one holds about 25 spools for about $700.
Another company that makes them is Ruggard, but these are for Camera storage, and NOT for filament storage. They only can maintain about 35% humidity. Good for camera storage, not good for filament.
I don't know why these are so hard to find or so expensive. They are quite simple in operation.
I have made a dry cabinet from the Ruggard dry cabinet. While the literature says 35 percent I have verified that if you set it at the minimum it'll maintain about 15% RH. I've verified with with 4 different hygrometers.
I designed a system that puts all of the spools on rollers and I print directly from it. I wouldn't necessarily use it to dry spools, you should use a heated dryer for that, however it's a great way to store and keep filament dry and to print directly from. I have a built a few of them in slightly different configurations for different printers, but it works great. I print 90% PETG and the improvement in print quality was huge.
My only complaint is that they don't make a bigger one.
The first picture is the display on the unit, and the second is from the hygrometer inside the unit. Last one is how I've got the rolls setup on bearings for printing and easy changing.
RE:
I think a some depends upon what your normal humidity is, but all these cabinets basically work the same, with desiccant and an automatic way to dry it, but the ones for filament probably add some more tweaks and increase the price.
My EDry cabinet has some vents that open and close but its the most expensive.
I'm not sure how the PAC cabinet is different, but it does work pretty differently at a cheaper price. It recovers much slower, but can maintain lower humidity.
