On 8/16/20 8:40 PM, Gene Heskett wrote: > And it ran about 5 minutes, broke the cup of the flexgear off at the disk > junction. Only 1.2mm thick there, concentrating the wall flex into that > relatively sharp corner. Can I fix that in cura? How?
Cura should allow you to specify the number of layers. In Simplify3D, I can set the number of bottom layers, the number of top layers and the number of side layers... all independently. As Chris and I have maintained, the outer layers largely determine part strength and the infill doesn't. I'm printing a small production run of structural parts and I had the slicer use four outer layers and 20% infill. They're very strong ABS parts. If I wanted rigid parts such as gears that were resistant to impact forces or layer separation, I might specify six outer layers, and possibly more. > Looking at that edge with a strong lens, I see 3 layers of wall, with quite a > bit of air > too. So I was still having plastic delivery problems even after > calibrating it according to Andy, where scale is set to deliver 100mm of > pla for a 100mm move command. That's a good calibration method but it assumes filament that is within specifications. I've recently encountered some filament that I bought on Amazon (with good reviews) that was 1.49mm in diameter instead of 1.75mm +/- .03mm. Undersized filament will cause under extrusion. You should be able to compensate with a slicer setting, within reason, but if the filament diameter is too small it may not feed reliably in some extruders. The software compensation can't compensate for absolute hardware limitations. Properly calibrated, adjacent layers of extruded filament should touch each other. You shouldn't be able to see any space between adjacent layers. The layers will typically be .4mm wide, on .4mm centers, so they touch. Maybe verify that your slicer knows what size nozzle you're using. It sounds like you've made a lot of adjustments to the settings in Cura and in the Marlin firmware, and it would be easy to accidentally enter a wrong value that persists and causes problems. It might be a good idea to return to known good values for Cura and Marlin. The people who have better luck 3D printing didn't need to do a lot of configurations. > Bruce mentioned TPU with an 85 or better shore as being more flexible but > I've not found that for sale anyplace. URL anybody? https://www.amazon.com/s?k=tpu+1.75 Warning - The Priline TPU was the filament I mentioned that had an outer diameter of 1.49mm instead of 1.75mm. Yoyi is pretty good TPU but a bit stringy. The higher the durometer (Shore A value) the easier the filament is to print because it's not as soft and stringy. The extruder has less trouble feeding the filament, and there are fewer problems with stringy parts. Each brand of TPU is different, but I generally use the following slicer settings for TPU: 1500 mm/minute for all motion 220C nozzle temperature No retraction 25% speed for the first layer, no cooling fan, 60C bed temperature. 100% speed for all subsequent layers, 100% cooling fan speed, 50C bed temperature Avoid crossing outer perimeter _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
