1 (edited by awptickes 2013-10-26 14:40:18)

Topic: regrind/recycled plastic

Is there any reason one should not use regrind ABS pellets from reject injection molding parts?

I'm looking at this stuff, re-ground Cycolac* Resin BDT6500, because they're one of the few cheap sellers who actually posts the material and the specifications of the material, and they state only one heat-cycle on it.

$32.44/10lb shipped isn't bad, right?

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Re: regrind/recycled plastic

That's a pretty good deal. In comparison, OSPrintingLLC sells 10 lbs of raw ABS with three colors of colerant for $53.99 shipped. (http://store.osprintingllc.com/ProductD … ABS_Medium) So the re-ground is a bit cheaper, though you'd need to take the colerant into account as well.

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Re: regrind/recycled plastic

I can't post a link to the eBay auction, but the shipping price goes way down when you order 20+ lbs. Goes to $50.65/20lb and $69.95/30lb.

I'm not crazy on using colorants, but I guess it's something to factor into the prices. At some point I'm sure I'll want to print something other than white.

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Re: regrind/recycled plastic

I just read an article that claimed that previously most plastic was sent to China to recycle (lower processing costs, for the usual reasons), and that China just stopped accepting foreign plastic, so they're expecting there to be an increase in domestic plastic recycling. So perhaps we'll see more of this going on?

Post when you see how it extrudes!

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Re: regrind/recycled plastic

MFI of BDT6500 is 1/4th that of MG94 (which is included in your kit).... so expect extrusion rates 25-50% of what you say with MG94.

$32/10lb isn't far from what MG94 costs from OSPrinting (~$45/10lbs, shipped) which is virgin material and is going to extrude speedily.

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Re: regrind/recycled plastic

It will be worse than that, because the flow doesn't scale linearly.  I have clear ABS (PA-758) that has a MFI that is 80% of MG94's MFI.  I typically get 14"/min with MG94, but the clear will only go 3"/min which is 25% of MG94's extrusion rate.

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Re: regrind/recycled plastic

Ian - are you sure about that? MFI is a measurement of how much polymer flows through a given orifice at a given pressure at a given temperature. It's pretty straightforward - there's no scaling involved, it's a direct measurement.

I think in the case of PA-758, the polymer's friction coefficient is different, yielding less force/melt pressure.