Problems with PetG

[Alibert]

I don't know. I do know that a filament that prints well one day can print with a lot of steam bubbles a few days after, so less than 48 hours is my estimate. It will depend on the absolute humidity it is exposed to.

What most people do not realize is that relative humidity is a totally meaningless number unless it is given together with the temperature. The difference between absolute and relative humidity is explained here: http://info.zehnderamerica.com/blog/...the-difference

The equilibrium of water between air (gaseous state) and the polymer matrix (dissolved state) is governed by the concentration of water in the air (which is itself a function of temperature). Putting it simply, if the concentration is twice as high (expressed in g/m3, not %RH), then there are approximateley twice as many water molecules hitting the polymer surface per unit of time, and thus twice as many have a chance of entering the polymer matrix thus contributing to the water uptake.

So, given max abs. humidity at 15 C it might take a few days, given max abs. humidity at 35 C it might take mere hours.

If you live in a (sub-)tropical area, store your filament air-tight when not in use.

PS: In case you are wondering, I am a chemical engineer by profession

[Bastian]

Attachment 9210Attachment 9211Attachment 9212
here it is. You can see the huge difference. the dried filament is so much better it is unreal. Mate, big thank you for the tips!! Now we have proven the concept and are ready to establish production lines! People, dry your filament and you will have incredible better printing results!

[Alibert]

Glad to have been able to help. The attachement links are not working however, could you amend them? Youcan insert pictures in your posts.

[Bastian]

20160411_181825.jpg here 1

[Bastian]

20160411_180125.jpg new print

20160403_092905.jpg old print with strings

[Alibert]

Indeed the same kind of difference I found. And more proof that those who claim that PETG isn't susceptible to moisture are just parroting a misinformed sales pitch.....

Happy printing and you might contemplate your own vacuum drying oven....

[NitroXpress]

Hi all,

sorry for the late reply...

I don't know where you buy such low quality filament, that you have to dry it bevore printing...
My filament comes in a vacuum sealed package.
I use 8 different colors of PETG filament with my printer, unpacked since 1-8 months and there is no quality difference.

I use a retract of max. 0,25-0,5mm.printer.jpg

Also see my youtube video, printing at ~390mm/sec.
https://www.youtube.com/watch?v=j_ATq9Rnghs

[curious aardvark]

wow - that's one hell of a printer !

So what brand pet do you use ?

[NitroXpress]

It is from https://reprapworld.com/?products/li...1590_1737_1682

[NitroXpress]

But the filament is only the "half rental"...
You need a perfect setup/calibration of your printer.

If you want to see "live printing" look here : http://itfs.dyndns.info:85
Sorry, but my internet upload speed is only 1 MBit

I tried different brands of PETG filament.
I think they provide the best quality/price ratio.
Be sure to select the filament with 0,05mm tolerance.

Also see my "boiled water test" https://www.youtube.com/watch?v=OxDOO06i5YU