Ok, this is good feedback. I can't seem to get it lower with these PolyMaker dryers, even with the airflow improvement pieces off Printables. I've seen others here recommend food dehydrators. Is there one that everyone recommends?

I use this dehydrator with these extensions:

https://www.printables.com/model/242300-dehydrator-tray-extension-for-commercial-chef-ccd1

$33 plus printing the extensions.

Regards,

Mark

Make sure it has a fully variable temperature control (I marked my preferred settings with dabs of white paint.)

They are designed to dry fresh vegetable matter that may be over 90% water so filament is easy for them.

Cheerio,

With dryers I'm getting the spools down to 18-23% humidity,

Borderline, check your dryer, you should be aiming for 10% or 15% at most.

Cheerio,

Posted by: @diem

Was the part originally designed for machining from metal?  Rising unconstrained curves are always tricky, they have a tendency to warp as the filament cools and if the part twists enough there can be a head-crash causing layer shifting like this.

I would use cubic infill, reserve the honeycomb for occasions when the very slight stiffness bias of cubic really matters.

Snug support might also hold the part in place a little better.

If at all possible the best way is to include a breakaway stabilising fin on each arm:

It can taper to a single extrusion width at the contact point.  The idea is to hold the arms in place until complete and then remove post printing.

Cheerio,

So, slowing things down a bit definitely helped. Upon closer inspection, you can still see some areas where it was struggling to hold the layer. I do believe it has something to do with this particular material (PETG-CF), since I haven't had any issues in PLA or regular PETG. It seems the material "swells" a bit after cooling, so maybe some of it's from that. With dryers I'm getting the spools down to 18-23% humidity, so not sure how much that contributes.


Thanks everyone for your feedback. I'll keep experimenting and see what else can be done to improve this material's printing quality.

Posted by: @raaz-2

Difficult issue, if the extrusion multiplier is fine for the filament. My second try would be to reduce the extrusion widths, so the filament stays a bit more "under the nozzle".

However, the blob on the nozzle should stay soft enough to just cause ugly prints, not a layer shift. Only if it comes loose, forming an obstacle for the nozzle somewhere on the print object. 

Posted by: @cjd

I had this happen recently on a PETG print because the nozzle was collecting gunk which eventually stuck to the print. Don't yet have a solution (but haven't been chasing it either, other priorities and haven't been printing). PLA is fine.

Difficult issue, if the extrusion multiplier is fine for the filament. My second try would be to reduce the extrusion widths, so the filament stays a bit more "under the nozzle".

However, the blob on the nozzle should stay soft enough to just cause ugly prints, not a layer shift. Only if it comes loose, forming an obstacle for the nozzle somewhere on the print object.