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Topic: Looking for Pellet Dryer design

I have found that drying pellets/masterbatch before extruding has a tremendous effect on the resultant filament quality.  At the moment I just spread out the pellets on a few oven trays and put in the oven for >4hrs at 50°C-75°C.  The wide temp range is due to the low temp setting of my oven - it cycles quite wide at low temps as it's not really designed for that - it's designed for cooking!

I saw a post somewhere where someone had designed and built a pellet dryer.  They had a step-by-step and some pics and a video.  I just don't remember where I saw it.  I'm not sure if it was here or Instructables or Youmagine or somewhere else.  I recall in the post that the author mentioned it dried the pellets really quickly and effectively (thoroughly).  It was kinda like a mini washingmachine with some holes in the sides and spinning with a motor, blew (hot?) air through it etc.  Does anyone remember seeing such a thing?  Please can you point me to it?

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Re: Looking for Pellet Dryer design

Lyman made something like that:

https://www.youtube.com/watch?v=o4F3e6K5Hxk

but a food dehydrator works as well:

ggalisky wrote:

Many different types of plastics need to be pre-dried in order to get good quality filament and prints. The plastics that encounter frequently that need pre-drying are PLA, Nylon, TPU, and PC (polycarbonate). There are several more plastics that need to be pre-dried, but for simplicity I only listed a few. I used a food dehydrator I bought off of Amazon to dry all of my pellets. http://www.amazon.com/Presto-06300-Dehy … dehydrator . The dehydrator comes with mesh plates, so you need to find a way to stop the pellets from falling through. I use this: http://www.amazon.com/National-Presto-D … ZNA913RBA. I usually let the pellets dry for about 10-17 hours. After drying I seal the pellets in a zip lock bag with a silica gel packet inside, and add a label so I know what plastic it is.

3 (edited by Superdave 2016-01-13 12:24:58)

Re: Looking for Pellet Dryer design

I have the parts gathered for a design I have in mind. It's basically a rotisserie toaster oven with the elements controlled by a PID.  All of the parts other than the drum came from a toaster oven that the timer burned out on.  The rotisserie would have a drum basket to tumble the material and a fan to move air.  But you know the story, busy at work and no time for pet projects.

If you build it they will come. Then they will make fun of it, tell you it's not worth doing and go home and try to copy you.
If a picture is worth a thousand words then being there is worth a thousand pictures.

(2) Stock Makerbot Z18s, Filastruder w/Melt Filter, Filawinder, Autodesk Inventor Design Suite 2014 .........so far.

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Re: Looking for Pellet Dryer design

this one? https://www.thingiverse.com/thing:912624

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Re: Looking for Pellet Dryer design

That's the one I was thinking of!  Thanks for finding that.

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Re: Looking for Pellet Dryer design

elmoret wrote:

Lyman made something like that:

https://www.youtube.com/watch?v=o4F3e6K5Hxk

but a food dehydrator works as well:

ggalisky wrote:

Many different types of plastics need to be pre-dried in order to get good quality filament and prints. The plastics that encounter frequently that need pre-drying are PLA, Nylon, TPU, and PC (polycarbonate). There are several more plastics that need to be pre-dried, but for simplicity I only listed a few. I used a food dehydrator I bought off of Amazon to dry all of my pellets. http://www.amazon.com/Presto-06300-Dehy … dehydrator . The dehydrator comes with mesh plates, so you need to find a way to stop the pellets from falling through. I use this: http://www.amazon.com/National-Presto-D … ZNA913RBA. I usually let the pellets dry for about 10-17 hours. After drying I seal the pellets in a zip lock bag with a silica gel packet inside, and add a label so I know what plastic it is.

Oooh - I hadn't seen Lyman's one.  Is that just a fan heater that he's aiming at the gismo?  I like the agitation of the pellets as that vastly decreases the drying time.

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Re: Looking for Pellet Dryer design

I just use a dehumidifier.  My printing room is currently 86F (iut is in the 40s outside) with 21% ambient humidity.  I wonder if this is sufficient?