Verifying you really have PETG  

RE: Verifying you really have PETG

Great question.  Look for labels under labels on the spool. Sometimes the folk rebranding filament will just paste over the mfg label. 

Postulating here: Glass temp is one way to determine the class of filament, but even that's unreliable because the eutectic point of compounds can be all over the map. Using solvents on the material is another way you can gain insight, but then some of the solvents you'd want to use are quite nasty stuff to have around.

It really comes down to trust, and why name brands can be worth paying for. 

RE: Verifying you really have PETG

I would like to know also, not for printing, but for recycling...

RE: Verifying you really have PETG

I have a few unlabeled spools and would love to know what the heck they are.  

RE: Verifying you really have PETG

Maybe not trust what's on the box but what's on the spool. Given their Prusament QC process I think the likelihood that that there's PLa on a spool labeled PETG is close to nil. 

RE: Verifying you really have PETG

@fuchsr

True with Prusament, but some companies do not label and Hatchbox has a propensity to peal off.  

RE: Verifying you really have PETG

@cwbullet

Oh, I totally get that. I have oodles of leftover filament or samples and no idea what material they are. I was responding specifically to the OP's mentioning of Prusafilament [sic] which I assumed was a misspelling of Prusament. 

RE: Verifying you really have PETG

Well, the label on the spool does indeed say PETG but for fun I test printed the configuration file with PLA settings and it worked fine, given it drips and blobs like crazy at PETG settings I am going to assume it must be PLA. Any additional thoughts? Thanks

RE: Verifying you really have PETG

@richardschreier

Can you tell the difference between butter and margarine by the melting point?

If the label says PETG, but your normal PETG temps creamify it, print it at PLA temps, but assume it is PETg for applications. Though, I probably wouldn't use a part made from it in a car.

ps: I've printed Prusament with a PLA profile... can't say anything bad happened. I've even printed PC with a PLA profile. Who knew?

RE: Verifying you really have PETG

Same here. I've printed PLA with PETG profile and vice versa. 

RE: Verifying you really have PETG

Good points - if it is too runny, it is PLA, if it perfect at 230-240, it is PETG.

RE: Verifying you really have PETG

Posted by: @tim-2

@richardschreier

Can you tell the difference between butter and margarine by the melting point?

By taste?  I am not tasting PLA or PETG.  

RE: Verifying you really have PETG

@cwbullet

They taste like chicken...

RE: Verifying you really have PETG

This doesn't apply for all filaments. But I have many spools of Real filament and their PETG is more shiny on the spool compared to their PLA. Most of the time I can pick the right spool without first looking at the label.

But the Prusament spools I have don't have that clear difference.

RE: Verifying you really have PETG

@fuchsr

Mmm, chicken.  

RE: Verifying you really have PETG

By taste? I am not tasting PLA or PETG.

Maybe not, but you can smell them.

Or rather, their smoke.  Burn the end of a scrap of filament and smell the smoke (just a waft, not a megasniff, do it away from the smoke alarm and over a bowl of water, you don't want burning drips of molten plastic hitting the carpet.) Smoke from scorching PLA and PETG smell quite different...

...but I don't know how much the pigment contributes.

Cheerio,

RE: Verifying you really have PETG

If it's Prusament, scan the spool's QR code and see what it says on the website. Then get in touch with their support. I've had issues with Prusament Neon Green PETG and after submitting photographic evidence of a manufacturing anomaly, they gave me a discount voucher for my troubles.

RE: Verifying you really have PETG

Distinguishing PETG from PLA should be relatively straight forward. If you print something and smell those lovely unhealthy fumes (also PLA isn't exactly health improving but not that bad, compared to other polymers). Especially PLA has a very distinct smell I think, butyric acid like? (well probably like lactic acid as that is its monomeric composition)  Just take a whiff of a trusted PLA of your choice and you know what I mean.

PETG doesn't smell like that all. It smells more like you would imagine molten plastic smells like. Not very strong but maybe soapy (if that is a smell) and headache inducing when smelling it longer (which you shouldn't I guess). Identifying PETG by its smell might be harder but PLA should be fairly clear.

Also PLA is harder than PETG but the more it hydrolyzes, the more brittle it gets. PETG is more flexible and a bit softer.

RE: Verifying you really have PETG

Make a temp tower, possible you need less temperture to print the petg.

PLA should smell different, print petg then print pla , to compare.

RE: Verifying you really have PETG

@peter-m

Good point.  PLA often smells sweet (not sure that is the right term).  It has a very distinctive odor.