Vacuum sealed? Yes or No

Help with printing with specific plastic filaments.
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asimbhuta
Posts: 9
Joined: Fri Jan 26, 2018 12:12 pm

Vacuum sealed? Yes or No

Post by asimbhuta » Sun Feb 18, 2018 7:30 am

Bought a bunch of PLA from lulzbot site and also a roll of t-glase via amazon (Aleph Objects Inc).

1 roll was sealed but not quite vacuum sealed. The t-glase looks like either there was no attenpt to vacuum seal it or the packaging has holes around.

Are all filaments meant to be vacc sealed? If so I need a chat with lulzbot and Amazon.

ScottW
Posts: 451
Joined: Thu Dec 10, 2015 1:00 pm

Re: Vacuum sealed? Yes or No

Post by ScottW » Mon Feb 19, 2018 11:20 am

They should all be vac sealed with a desiccant pack inside. It isn't important to have every bit of air sucked out -- that's what the desiccant pack is for, to get any moisture from remaining air -- but the bags should definitely be sealed.

But even if they are sealed and have a desiccant pack, it is no guarantee they have been that way their entire life. I've had rolls of Nylon, PETG, and PCTPE all arrive from Amazon perfectly vac sealed with desiccant packs -- only to find the filament full of moisture (popping, steam, bubbles). I even got a replacement reel of PCTPE direct from the manufacturer that (despite arriving in a vac sealed bag, with desiccant) was full of moisture.

I gave up and bought a modified food dehydrator. I now bake every roll of filament as soon as it arrives, before placing in sealed containers with desiccant for storage. Obviously not every roll needs it, but many do -- and I was tired of sending them back, hoping for a dry replacement that sometimes never came. Baking temps for removing moisture: PLA 45C, ABS 60C, Nylons 65C. Generally 3-4 hours will do the trick for most filaments, although some Nylons can take twice that long.

asimbhuta
Posts: 9
Joined: Fri Jan 26, 2018 12:12 pm

Re: Vacuum sealed? Yes or No

Post by asimbhuta » Mon Feb 19, 2018 1:06 pm

Thanks for the reply. I guess it is something worth me thinking about.

At the moment, I’m not too concerned about the quality of the prints as I am mainly printing for proof of concepts and prototypes rather than something closer to a final product. But then again I don’t know how bad the filaments are and whether it could simply cause failed prints.

Do you think it is worth me placing the filaments in an oven at the temps you mentioned? Also what temp would you suggest for t-glase.

I don’t have a food dehydrater or similar but I guess an oven would be better than nothing right?

ScottW
Posts: 451
Joined: Thu Dec 10, 2015 1:00 pm

Re: Vacuum sealed? Yes or No

Post by ScottW » Mon Feb 19, 2018 1:22 pm

You can try printing with it. Moisture will show up as steam, popping, bubbles, or (at lesser levels) oozing and stringing. If it prints acceptably for what you need, that's all that really matters.

I have successfully dried wet filament in a household oven. The problem is that most ovens are not very precise at the temps needed (45-65C, or 113-149F). Get too hot, and you'll melt the filament or the spool. I used a remote temperature probe, and manually turned the oven on for a couple minutes from time to time -- being real careful to stay at/below the desired temp. It's a pain, but it can be done.

The information I have suggests the following temps/times:
PLA 45C 4hr
ABS 60C 2hr
PETG, Nylons, TGlase, PETT, etc. - 65C 8-12hr

FYI, here is a link to some videos that show what happens when PCTPE is really damp....
viewtopic.php?f=29&t=6329&p=36044&hilit ... ure#p36044

asimbhuta
Posts: 9
Joined: Fri Jan 26, 2018 12:12 pm

Re: Vacuum sealed? Yes or No

Post by asimbhuta » Mon Feb 19, 2018 6:19 pm

Thank you. I’ll extrude and test print to see what its like.

If its anywhere near as bad as the video in that thread then i’ll give my oven a try. All part of the learning process.

olantigh
Posts: 34
Joined: Fri Feb 02, 2018 11:56 am

Re: Vacuum sealed? Yes or No

Post by olantigh » Tue Feb 20, 2018 12:42 pm

Yeah I noticed when I ordered some ABS from amazon that the bags had been sliced to get them in to the box- so I put them in to a sealed lunch box with the bags that came with them- had no problems printing out.
Although I thought PETG didn't absorb moisture? but saying that the ones I ordered the other day are in sealed bags?- I check everything I get through the post, especially after that first delivery from amazon.
And I've bought every sealable lunch box over 5 litres in volume from the local supermarket- just the right size for one reel of filament.

ScottW
Posts: 451
Joined: Thu Dec 10, 2015 1:00 pm

Re: Vacuum sealed? Yes or No

Post by ScottW » Tue Feb 20, 2018 12:53 pm

olantigh wrote:
Tue Feb 20, 2018 12:42 pm
Although I thought PETG didn't absorb moisture?
PETG definitely absorbs moisture. Perhaps not as quickly as Nylons, but it definitely does. I had a roll of PETG (also from Amazon) that was oozing and leaving all kinds of blobs and artifacts. After baking, it produced a perfect print with the same gcode.

olantigh
Posts: 34
Joined: Fri Feb 02, 2018 11:56 am

Re: Vacuum sealed? Yes or No

Post by olantigh » Sat Apr 07, 2018 1:46 pm

That's good to know, although I haven't got round to using the PETG I got as yet- I thought that keeping it in sealed containers was probably a good idea.

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