Very VERY impressive! Well done @polymaker. I'm fully team dehydrator, but I love the way the dryer directly integrates with the storage boxes. Adding this to my printshop. Thanks for the review Igor, this is the one I was waiting for.
As far as I know, blue silica gel contains cobalt chloride which is toxic. It is forbidden in the EU. So I would switch to orange silica gel which also changes colour. Orange beads are supposed to be at least less toxic (supposedly non toxic) and this is what I have at home. Thank you for your series on filament dryers. Was waiting for this.
@@suivzmoi yes, i mentioned in the above post that it is suspected to be safer because EU(where I live) definately categorises the blue as a carcinogen. The orange ones, I can't say for sure. In any case, I always use nitrile gloves in my hobbies of 3d printing, microelectronics, etc. When I think it is appropriate for handling fluids or materials, cleaning, glueing, you name it. Normal safety precautions as I advise everyone to do the same.
That center spool roller is such a great and thoughtful design. However the hygrometer being that close to the dessicant is going to be highly inaccurate in my testing with various Bambu AMS dessicant mods but since its color changing silica it doesn’t matter too much.
Hydrometer next to the beads? 🤨 My beads (I got them in a 4kg bucket at an aquarium wholesale store - much cheaper and good quality) change to a green colour when exposed in my app to room temperature with +/-45% moisture after 2 days. Just to give you an idea. I take my beads out of the AMS when it reaches 20% and then they are a rusty dark orange colour instead of bright orange. Above 20% moisture in the AMS and spider webbing appears (more) in my PLA prints. So the colour isn't a good indicator in my opinion. Especially when using more hygroscopic filaments. Also, 50°C for PLA...I always use 45°C for 6 hours. From my limited understanding, some PLA softens at 50°C. Correct me if I'm wrong. No, thank you Polymaker, I'll stick to my Eibos Polyphemus and DIY storage.
Not sure what humidity sensors you're using, but if those are DHT11's you can switch to DHT22's which have more accuracy and should be relatively compatible. I like the design as it's an evolution of the popular community cereal box design, but their per-container price is a tad on the high side.
Dr Igor, I have been researching filament dryers and am so far not very impressed with what I am seeing in the market. Most of them do not vent hot air and those that do are not looked at closely enough for that function. Especially important for products like these which perform both drying and storage functions. I find the built in hygrometers to be quite misleading since they are RH based and inversely correlated to air temperature. In my opinion RH alone is only useful to tell if the heater is working. What I find more important is absolute humidity or at least partial pressure of water vapor which will reveal how well the product is actually getting rid of moisture. for example, a poor dryer will see RH decrease with increase temperature but will show partial pressure of water vapor accumulating over time (no venting of hot moist air). So I did some calculations and found that for something like Polydryer with
Absolutely! Scientific snake oil! You can see from the graphs: the RH graph is just the inverse of the temperature graph! To dry with hot air you have to vent the hot air and replace it with cold. This is why clothes dryers are so expensive to run: they are effectively heating massive volumes of air. Dryer boxes need a separate exhaust fan. Heat the internal air up to temperature with the internal circulation fan running. When it is at temperature, run the exhaust fan for a period of time to replace the warm wet air with cold dry air from outside. Repeat as necessary. It would also be good to weigh the spool in the box so you track loss of water from the filament directly and stop when it stops decreasing to save energy.
Your science is correct, but your understanding of how the polydryer is constructed is not. It isn't airtight when connected to the base. The heater blows hot air into the back of the filament box and the hot air is exhausted at the front of the box through an opening back into the base, which is open to atmosphere. The seam is not sealed. The air movement is the same as any clothes tumbledryer moving along both the thermal and partial pressure gradients. I actually set my dryer on a scale (as you also cleverly concluded) and routinely see between 1 and 3 grams mass reduction over 6 hours, which matches my estimate within 25%
@@kg4lod That is somewhat encouraging, but I still think they could do better by building a weight sensor into the base and controlling the exhaust either with an automatic shutter or an independently controlled exhaust fan. You do not want it to start exhausting until it has reached temperature and humidity equilibrium and it is wasteful to heat the air whilst it is exhausting. Stopping the process and sealing the chamber once the weight stops reducing would save energy and make the process safer.
@@john_hind Completely agree. Your absolutely right that there are a lot of low-hanging fruit that could be achieved with just a tiny bit more hardware and significantly more sophisticated control.
@@kg4lod your reading comprehension needs some work. I said dryers that don't vent should not even be worth the time to review and those that do vent, like Polydryer, needs to be reviewed specifically on how well they actually vent.
3 months later, I must ask again… please add this data to your website :) You commented a few months ago that you would add it, but it’s still not there.
Oh, it is sold out already :( I really like this system, and hope extra boxes are super cheap :) Anyway, the beep, and the blue color choice makes it sound/look cheap, which is a pity.
That beep i nasty, a deal breaker for me :). Isnt the temps a bit low at maximum power, especially for nylon. Maybe its possible to improve a bit with better insulation, but it would be any improvement over my food dehydrator temperature wise for example.
I use the Polymaker Polybox for a filament dry box , connected reverse bowden into the enclosure and to the hot end on my printers. I use the Slice Engineering desiccants inside of the silica and pre dry materials in the Print Dry Pro. This dryer from Polymaker is a little disappointing but does have some interesting things. I wish it wasn't just a one at a time dryer and being locked into those storage containers (what do those cost?) seems iffy for me. I applaud the accuracy of the temps (yay, sensors that work!) but like you said, that side outlet doesn't really speed up the lowering of humidity from inside. (Maybe they need a basic lesson in convection and thermal dynamics?) Not a terrible unit but room for improvement.
the side outlet is marketing bs, there is no side vent, the moisture goes from the filament into the dessiccant, like it should in a proper dryer. also, somone designed a 2in1 adapter already, so you can dry two at the same time.
Buy a Eibos Polyphemus man. I can recommend it. Rotates the spools and everything. Use cereal boxes with an hygrometer. Polymaker put the hygrometer smack dab in the middle of the silica beads. That thing will be way off.
A video with some long term experience if the advertised 5% over 30 days hold true would be very much appreciated. Doesn't have to be long, just some data and what your experience is after some time using the dryer and the box.
I really loved the original passive PolyDry box industrial design, and was sad that it was just a box with no heat or fan at all, so when I heard they did this I was ecstatic... but then I SAW it, and good god is it UG-A-LEE. It's functionality potential though is huge. I'm considering buying this one now in addition to my Space Pi, but not until someone posts an STL for the spare containers, I want to keep several of these but not for $30/ea. It's a great idea having it be a modular design, needs some improvements but it's overall use makes up for shortcomings it seems. Man is it ugly though.
I want to say they were foing for the 'Pelican case' aesthetic, of function over form, but that's no excuse for the CMF of the base that looks like a soldering iron station from the '80s.
Realistically, how long would you have to run the dryer for PLA? Lot's of good data, but no real-world analysis to make it digestible. The sponge might be the closest experiment, but that might not be comparable to plastic. For example, if I wanted to just remove 90% of the water from my spools, could I just leave it in the dryer for 30 minutes?
I love this whole series of vids! I ended up buying the Creality Space Pi (something a lot of reviewers miss is that it does have a hole to release moisture it's just very tiny and looks like a manufacturing injection mold dimple, it's a hole though) for me there's a night and day difference after drying so I've actually been going through my whole collection and drying every spool with it.
57c is rather low. Have an inexpensive food dehydrator able to reach 90c. Have read that some filaments need higher heat than this unit's heat output to unbind water molecules from the polymer. Is this safety listed? Haven't seen a filament dryer yet that has any EU or US safety listing.
