PLA/PHA Filament help

[cjalas]

Hi all, I've been testing out various new filaments (exotic and others), and came across some PLA/PHA Mixed filament from MeltInk over on Amazon.com; I had a bad experience with the first roll of material, and thankfully the company sent me a replacement free of charge (after I returned the original to Amazon) -- as well as some standard PLA colored samples -- but I'm still having a frustrating time with the prints.

I've tried anywhere from 180c up to 220c on the extruder temps; the problem is the higher I go in temp, the more brittle the prints become, and it seems like the infill isn't quite "infilling" properly. I've managed, at 180c, to get a DECENT print... but the overall structure is still fairly brittle and much easier to snap in places than any standard PLA material I've used to print.

200c
2016-03-07 14.53.42.jpg

190c
2016-03-07 14.53.49.jpg

180c
2016-03-07 14.53.54.jpg


As you can see closely, there seem to be gaps in the infill sections, and the overall prints become more brittle and chalky the higher the temp. I don't think I can go less than 180c though and still get the filament to melt; what do you all think could be the issue with this filament? Anyone else have hands on experience with PLA/PHA?

[LambdaFF]

Hi,
I once bought some PLA/PHA from colorfabb. It's not a bad product (except for the price perhaps). Didn't have the issues you have at least.

Regarding the issues you seem to have ... the mechanical properties certainly point to a material of poor quality but to me the infill holes you experience are probably also due to :
1/ possibly underextrusion due to bad diameter.
2/ most certainly too fast speed
3/ possibly not enough overlap of infill on external shells.

[mikethebomber]

Agreed with Lambda. I also use Meltink, but I have my speeds way slow. I never go much past 45mm/s and have had great success.
I think I tried it yesterday at 60mm/s and it worked great, but it looked like stringing was happening a little more, so I upped my retract settings, much better now.