SoliForum - 3D Printing Community — Is there a better feeder screw ?

Re: Is there a better feeder screw ?

2014-08-11T06:34:49Z

Using an oven is too expensive. Cheap filament becomes not so cheap but "i made it my self" filament.
Air drying would be quicker and cheaper then using an oven for 2 hrs.
His drier container needs to have a cone shape on one side to make it easier to unload.

When i get rich, ill buy his setup Its freaking awesome. Its like a mini factory that has it all.

Now my biggest question is: Where do i find 18-24 page rated micro cut paper/cd/dvd shredder for cheap, so i can use it to shred plastic such as milk bottles and other stuff as well as scraps from printing.

I attempted to do just that with my 12 page rated shredder and it was OK but not perfect. I had to run pieces thru couple of times because some were not broken apart but results were very impressive.
http://www.soliforum.com/misc.php?actio … mp;preview
http://www.soliforum.com/misc.php?actio … mp;preview

By the way, does anybody know how to post an image while forum doesnt provide direct link to image uploaded ?

Re: Is there a better feeder screw ?

2014-08-11T06:23:04Z

Hugh Lyman has an cool filament dryer in one of his videos, but I don't think he ever posted the files. It wouldn't be hard to recreate.

Re: Is there a better feeder screw ?

2014-08-11T04:17:43Z

Darn it, another thing to buy
Hopper can probably be eazy to design and print, but screen and hair dryer with variable speed (low) will need to be searched for at local thrift store.

But thats very very very cool !

Thanks !

Re: Is there a better feeder screw ?

2014-08-11T04:03:32Z

A hopper with mesh screens on the sides that blow hot, dry air up and through the hopper.

They have to do this for three reasons:

1.) They cannot tolerate any variation in their material properties. A typical industrial hopper would hold 6-12 hours of material, and industrial machines are even more sensitive than DIY machines since they process so much faster.
2.) Factories are typically not HVAC'ed, and often damp/humid.
3.) They do not store the material sealed - it arrives in big cardboard boxes, called gaylords... or sometimes train cars. Thus they must dry it at some point, so best to dry it right before extrusion.

For DIY stuff, it seems drying it well before use, and only adding a few hours at a time of material (so material isn't sitting in the hopper all day) works well. Wouldn't hurt to use a lid. I've only run PLA for 15-20 hours total, others here are probably far more experienced. I prefer ABS because much of what I print has to withstand high temperatures.

Re: Is there a better feeder screw ?

2014-08-11T03:34:13Z

How do "pros" dry it in the hopper, what do you mean by that ? Removable hopper with a lid or something ?
Thanks !

Re: Is there a better feeder screw ?

2014-08-11T03:26:28Z

http://www.natureworksllc.com/~/media/T … wn_pdf.pdf

90C for 2-4 hours is appropriate. I would probably aim for 80C and closer to 4 hours to avoid melting the pellets, since Tg is around 70C.

Sealed and silica pack does not mean its dry. Not at all. The pros dry it inline, while its in the hopper - that's how important it is for there to be no moisture.

Re: Is there a better feeder screw ?

2014-08-11T03:17:44Z

I had it dry to begin with, it came sealed and with silica pack inside. It worked fine untill it absorbed moisture causing all the issues above.
I am drying it right now at around 90c (cant tell exactly) in a toaster (mini oven with built in air circulation fan) for about 1hr +
Should i go 100 ? I dont know if i can get temp exactly since its a kitchen appliance and not a drying unit with sophisticated term-monitoring system like the one came with filastruder.

Re: Is there a better feeder screw ?

2014-08-09T12:14:41Z

Have you dried the PLA? If so, how?

Is there a better feeder screw ?

2014-08-09T10:19:53Z

I cant get my thing to extrude, it keeps moving pellets around and not pushing them thru unless i press it down with something. (mostly finger)
Is there another feeder screw or what ever out there that i can try ?
It would go with good rate and then stop, sag and stretch and finally fall out with big blob of PLA.

ABS pellets that came with the unit were very nice but this PLA i bought has rounded bb's that just keep on slipping thru the shaft like nothing is pushing it at all.