Hi. Most of our use of our BL X1 Carbon is for PETG/CF, for medium to large engineering parts. We routinely use 3. Support G (or whatever the current name for this is) as most of our parts have overhangs. It took much effort to get this combination working with reasonable quality and reliability in the face of nozzle blocking caused by overheated filament.
The next challenge for us was dealing with PETG blobbing on the exterior of the 0.4mm nozzle, about which much has been written on this forum. Overwatch of printing every hour or two was required plus pauses for cleaning and polishing of the nozzle exterior.
While we managed to improve things with our default 0.4 nozzle through the process tweaks reported on this forum, large PETG/CF part builds are still far from a ‘lights-out’ process. So we recently switched to a 0.6 nozzle, to try and develop something more reliable. Our impression is of less blobbing, but we have a new problem which is top surfaces built on top of Gyroid infill are reliably very poor. Sometimes we see holes, and always we see unevenness.
Key settings in our current process recipe
Quality
- Layer height 0.2; initial layer height 0.28; all linewidths 0.62mm
- Thick bridges tickbox enabled
Strength
- 5 wall loops
- 4 top shell layers/0.8mm
- 4 base shell layers/0.8mm
- infill type Gyroid density 30%
Speed
- All speeds limited to 100 - 150mm/sec except initial layer and bridges which are 35mm/sec
- Infill speed 150 mm/sec
Support
- We use manually minimised Snug Default supports, with Rectilinear support style
- Top Z distance and Bottom Z distance both set = 0.
I’d appreciate any feedback concerning our top surface integrity problem. I suspect the Gyroid infill onto which we are building top shells may not be ideal, or perhaps it is not dense enough, but I’m shooting in the dark.