1 Topic by insta

  • insta
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Topic: Questions about PET

(haven't gotten around to the ballistic nylon yet...trying PET first)

I got this stuff from eBay, and while I'm waiting for details from the seller for Melt Flow Index, I had a question about the melting temperature vs. what I should be filastruding at.

The pellets are strangely white, which is what the auction said.  He said they turn clear when run hot enough.  He also says the melting temperature is ~ 250C.  Now, 230C is what I print Taulman PET at, which does turn out approximately water clear.  I know that Taulman PET is a different blend, and I'm thinking the 250C in the auction is for injection molding which I'm not sure applies to us.

I tried extruding at 150C which was a bad idea, so I upped it to 175C.  The plastic right out of the nozzle was clear, but cooled to a milk jug white, just like HDPE.  It was also very slow, which is why I'm inquiring about MFI.

Ideas on what I should be trying to extrude this at?

2 Reply by insta

  • insta
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Re: Questions about PET

I have a datasheet!

http://ws.eastman.com/ProductCatalogApp … me=Generic

3 Reply by redback

  • redback
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Re: Questions about PET

Did you do any drying to the pellets before extruding?

have you tried printing the milky filament? it might go clear when you print it.

4 Reply by insta

  • insta
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Re: Questions about PET

Updates on PET:

I had a lot of problems with it so far.  I still got groaning and popping from the machine at 175C, so I tried 215C.  It flowed better, but after several hours I only had a meter of filament, and it was obviously carbonizing.  I removed the nozzle and the pellets had made it all the way to the end, encased in a matrix of burnt PET goo.

I'm going to leave the rest of this up to Taulman.  If anyone wants the remaining pellets (probably 4.5lbs worth) they're yours for shipping.

5 Reply by insta

  • insta
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Re: Questions about PET

The seller spontaneously refunded me half my purchase price, without me asking.  Hella awesome considering I was treating it as R&D.  Not sure if you're reading this Ryan but thanks dude cool

6 Reply by insta

  • insta
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Re: Questions about PET

Same seller is preparing a grab-box of plastics for me.  Nylon, HDPE, PP, and two other types of PET.  Yay!