3D Printers, Makers, DIY hacks, solutions and post printing tools

Great comments, article. However, You do not have to increase the temperature even one degree and get the same results so long as the water doesn't have a chemical bond to the plastic, I do not know of any. The Teten Equation is one of many: P = 0.61078 exp(17.27 * T / ( T + 237.3)) where temperature is in Centigrade and pressure in Kilo-Pascal.

To dry a filament the vapor pressure must be lower around the material. Thus water molecules will migrate out of the filament. A material that wants the water more then the filament at the temperature of the materials will remove water from the filament. Activated carbon and some materials sold to remove water may meet this requirement. Many can be then dried out by changing the temperature which raise the vapor pressure of the water in the material above the vapor pressure of the air also heated. The molecules will migrate out of the absorbing material. Obviously the method to dry the filament is the same as the absorbing material. However, the absorbing material may handle heating better. I can assure you that activated carbon will be easier to heat up to dry it out.

Sorry mate, I do not print with carbon activated filament, nor do I have in this group interests for academic research with paper writing finalities.

This is a group for makers, inventors, strugglers, we seek the most efficient, repeatably method possible, that accomplished the task without giving us a headache.

I found a cheap reliable way, tested it over a year, it works, I don't even have to be in my lab when it dries, I just set the timer for 15 hours, if I am back in 6 is OK, if I am back in 15 is OK, take the spool, chuck it in the plastic bag, vacuum it and seal it.

End of story.

If you have a carbon activated method as cheap, easy and reliable like this, show me how to do it, for that is the only thing I did not understood from your comment, how, how reliable, and how it saves me time and money, and does the job effortlessly.

Are you a maker? Show me how.

Mate the activated carbon is not in the filament but is used to remove water from the filament. Carbon is used to make filament black and to be less damaged by solar radiation.

Cheaper, well that depends. The cost of a very accurate controlled oven compared to a bag of activated carbon? That activated carbon can be heated to lower it's internal water content, humidity it above which it will remove water vapor, by a poorer controlled oven and hotter since carbon doesn't melt. You have to deal with dust as a negative. But some of the other materials do not have as big of a dust problem. So if your using that accurate control oven daily then the cost is balanced against the hassle and cost related to using something like activated carbon.

How to do it. The manufacture of the carbon or other material should have the information to use it for humidification. Why is because it is very common application. You have it is generic pill bottles and in products that you purchase. They should have a chart for reusing the material. If not the internet will have the information. And the last resort is a chemistry handbook. In my first job before the internet existed I used the handbook to test two materials for recovery of Toluene vapor and striping it out of the absorbing material. PS I am not a chemist.

Hey Thomas,

If you didn't got it that I made a joke when I said Carbon Activated Filament, than ... huh...

Than the cost of the controlled desiccator is una tantum, for the rest of my life I only pay a few dimes of electricity each time I dry up a filament.

The ones ready made, I place the filament inside and it shows me how many grams it weights, I can dry it up or just keep it dry while using it in printing, hence when printing is done, the remaining filament is dry and ready to store in vacuumed bag.

No black dust in my room, on my hands, in my nose.

As I said before, are you a maker? Sow me how you made it and how it brings you advantages (not only moneywise, but mainly hassle saving, time saving, etc.)

I showed you mine, show me yours.

The heat needed to dry the filament would be spent in drying a descant also so this is not a factor. The factor is how much and how often one needs to dry the filament. The trade off is the cost of the equipment. I have a PLA and an ABS reels of filament in a box with a descant. And am starting to add moisture to the air. Turn off my humidifier for a few day and all I have to do is set the filament out. I can put the two dozen descant bags I have collected from pill bottles and other products in the microwave or oven after a dinner is cooked to dry them out. Not going to use a chart. Throw them back into the box and close the lid. No problem. I would be foolish to purchase a drier. The story is different if I were making many parts on multiple machines and needed may reels of different colors and materials. My goal was to broaden the range of people's level of need and usage in this discussion.

Even for a person with dozens of reels of filament a descant is put in the boxes that are used to store his filament. It is better to prevent the absorption of water then to have to cycle the filament through the drying oven. I worked with Saran a little at Dow Chemical, Midland Michigan, my first job plant site. It is heat sensitive. Hydrogen is replaced with Chlorine to the carbon chain of the plastic. Less stable which is why it is heat sensitive. Saran is not recycled. All plastics have some level of heat sensitivity. Drying filament out does have a negative effect be it slight. See a black speck in a plastic product is caused by a few molecules of plastic hung up in the extruder breaking off after they broke down and became weaker, brittle. We see it in the filament extruder heads.

Well I prevent the absorption of water by keeping the reels in vacuumed bags, no air, no humidity. I only dry them while in printing to avoid absobtion, cannot print them out of a vacuumed bag, ain't working.

Unfortunately I have too many reels, based on materials, materials mix, and sometimes colors, but to me colors are not that important as material structure, after all I can paint the prints if I want that.

However thank you for sharing some actual method finally, some of our coleagues in this group might draw inspiration and get some help, and after all this is why I have set this group for, to help the others, but not alone, don't know them all.

I'm using ziplocks and desiccant and have filament that is 1 year + old and prints great still.

You might not be living in the UK, where it rains 3 times a day.

True, and a good point. Still, I'm in Oklahoma USA, and our humidity was 90% + for many moons (months) this last year although we are well air conditioned here.

Your on the right track with putting filament in a vacuum. I worked on a lot of AC in homes and cars and ac Freon is very hygroscopic so much so it would pull moisture from the atmosphere even thou it was in a closed system and under pressure. We would put the under a vacuum witch would have one big advantage witch is to lower the boiling point of water. We would place our shop light on the receiver dryer very much like a desiccant bag in this case and it had more than enough heat to boil the water out of the receiver dryer a much larger unit. I use a simple vac pump and rubber hose and zip lock bags and have no problem with moisture. Placing the filament by a sunny window or by a heating vent gives plenty of heat and you don't need to do it all the time. If you have a good seal and the bag gets lose vac it down again. Just like the gauges jump on a ac unit the bag will get lose as the water leaves the filament.

All you have to do is use a food dehydrator. I have a round model with many trays. I cut out several of the center supports. Put a spool in the center, close the lid and turn it on. It won't get too hot and should work in 4 - 8 hours. I used to have a lot of problems with Stratasys ABS in a Dimension machine, and especially with the support. Once it's dried, it should work like new. The dehydrator costs about $30.00.

Dehydrator looks like a nice hack to dry it up, but to keep it dry in a country where it rains 3 times a day, vacuumed bags help a bit.

Also to keep it dry while printing, the dedicated dryer helps a bit, especially an open frame machine, the newly enclosed machines that have controlled temperature in the printing cube and the spool inside, they are best thing, but costly, heavy and hard to hide in a flat.

I live outside Houston, Texas. We have high temps and an abundance of humidity.. Try it. Simple easy way to dry the material..