Using heated bed to dry filament  

  RSS
towlerg
(@towlerg)
Honorable Member

I wonder if its possible to use the heated bed to dry filament?

Posted : 09/08/2020 1:21 am
Karl Herbert
(@karl-herbert)
Famed Member
Posted by: @towlerg

I wonder if its possible to use the heated bed to dry filament?

If the printer is placed in an enclosure and you reach the required temperature/filament, this is theoretically possible. But I think that this will only work well with PLA and PVA, maybe also TPU.

 

This post was modified 1 month ago 2 times by Karl Herbert
Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen....
Posted : 09/08/2020 2:28 am
gkas
(@gerrykaslowski)
Eminent Member

You can make a drying cabinet really cheap. I bought an inexpensive food dehydrator. I didn't want to cut up the original trays, so I bought a 5 gallon work bucket for another $4. I then printed the  CAP_BRACE.STL from http://www.thingiverse.com/thing:1618037   This allows me to slightly suspend the inverted bucket off the bottom of the dryer. The dryer has a nice temperature dial on it. This holds at least 3 spools. It works very well.

Posted : 09/08/2020 9:02 am
jsw
 jsw
(@jsw)
Honorable Member

I would use a low temp electric oven, preheated and stabilized to the drying temperature.

Posted : 09/08/2020 11:16 am
clemens.m
(@clemens-m)
Reputable Member

@gerrykaslowski

Did you ever measure the temperatures you receive, when you put it for example to 65 °C? I have the same food dryer as in your link and mine had a very big histeresis in temperature. That was the reason why I used a small Arduino, an electronical relais for switching current, a poti for temperature selection a small display and a digital temperature sensor. This helped to get the temperature close to the selected value (about +/- 1°C).

Before changing temperature control I destroyed one spool of filament by too high temperature.

Best regards, Clemens

Posted : 09/08/2020 11:53 am
Yveske
(@yveske)
Trusted Member

I use this one https://weckenonline.com/dejelin-nutridry-nd500s-voedseldroger.html
You can attach/detach the middle of each tray adhoc, extra trays are available

Greetings,
Yveske

Having problems with bed adhesion every morning......
Posted : 09/08/2020 1:07 pm
Yveske
(@yveske)
Trusted Member

Having problems with bed adhesion every morning......
Posted : 09/08/2020 1:17 pm
gkas
(@gerrykaslowski)
Eminent Member
Posted by: @clemens-m

@gerrykaslowski

Did you ever measure the temperatures you receive, when you put it for example to 65 °C? I have the same food dryer as in your link and mine had a very big histeresis in temperature. That was the reason why I used a small Arduino, an electronical relais for switching current, a poti for temperature selection a small display and a digital temperature sensor. This helped to get the temperature close to the selected value (about +/- 1°C).
 

Before changing temperature control I destroyed one spool of filament by too high temperature.

Best regards, Clemens

I hit it with may laser thermometer a few times and it was reasonable. I wasn't concerned. I kept the temps pretty conservative.

Posted : 09/08/2020 5:49 pm
towlerg
(@towlerg)
Honorable Member

@karl-herbert

Hi

what is the source of the drying time/temps you posted?

Posted : 09/08/2020 9:49 pm
towlerg
(@towlerg)
Honorable Member

Thanks for the input, but nobody addressed the original question.

On the subject of food dryers, what process is used to ensure the the exhaust air is not just replaced by more wet air?

 

Posted : 09/08/2020 10:10 pm
Karl Herbert
(@karl-herbert)
Famed Member

@towlerg

Just placing it on the heated printing plate is not sufficient. You need a closed installation space with stable and accurate temperatures.
I can't remember the source of the drying temp. It is already about 2 years old. These are only rough approximate values and can deviate somewhat with the large number of filaments. But I would rather use a lower temperature for a longer drying time than a too high drying temp.

Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen....
Posted : 09/08/2020 11:19 pm
Yveske
(@yveske)
Trusted Member

@towlerg

I also use it to dry coloured silica gel. If left in the open the silica gel turns pure black, after taking a ride in the food dryer it returns to its light orange state without a problem. So I wouldn't worry about the capabilities of the food dryer

This post was modified 1 month ago by Yveske
Having problems with bed adhesion every morning......
Posted : 10/08/2020 6:10 am
towlerg
(@towlerg)
Honorable Member

@yveske

Thanks for your input.

"So I wouldn't worry about the capabilities of the food dryer" I'm not concerned, I just want to know by what process they work.

Posted : 10/08/2020 7:06 pm
towlerg
(@towlerg)
Honorable Member

"Just placing it on the heated printing plate is not sufficient" hard to say till I know how they work.

"...with stable and accurate temperatures." I rather suspect that my printers heated bed has those properties.

Posted : 10/08/2020 7:09 pm
Yveske
(@yveske)
Trusted Member

Quick Google

"There's the same amount of moisture, but the relative humidity of the heated air is much less —the warmed air can “hold” a good deal more moisture than the cool air. ... It's just that, at higher temperatures, water molecules are more likely to go into the vapor phase, so there will be more water vapor in the air."

So the warm air escapes at the top of the food dehydrator and takes with it the moisture it collected from within your filament.

Having problems with bed adhesion every morning......
Posted : 10/08/2020 7:52 pm
Karl Herbert
(@karl-herbert)
Famed Member

https://all3dp.com/2/how-to-dry-filament-pla-abs-and-nylon/   ideally vacuum-sealed after drying.

Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen....
Posted : 10/08/2020 8:49 pm
towlerg
(@towlerg)
Honorable Member

@yveske

"So the warm air escapes at the top of the food dehydrator and takes with it the moisture it collected from within your filament." So with the addition of a cover with suitable vents my idea should work. I guess the principle problem is getting room temp/humidity air into the cover without heating it too much.

Posted : 11/08/2020 12:24 am
Yveske
(@yveske)
Trusted Member

@towlerg

Yes it should more or less. I don't know how fast the build plate will heat up the cold air before it starts rising.
It will be a fun experiment, but don't know how cost effective (money, build time and drying time) it will be compared to a real food dehydrator.

Have fun,
Yveske

Having problems with bed adhesion every morning......
Posted : 11/08/2020 5:52 am
Share:

Please Login or Register