lewis-levin

Illuminarti, so as long as I save the gecode (I am using UM1) I can pick up the settings? I'll give that a try--sort of self-documenting. Thanks.

Well, everyone will have different preferences and one should use what gets the job done. For me, several things made the difference: object doctor can almost always find "holes" and seal them clipping plane (non-destructive) and section can put a plane through just about anything and seal the cut ends far more reliable stl import and export (or DAE, which seems more reliable) real 3d: very few model errors curves and curved surfaces that hold up as 3d I used Sketchup free and pro (as expensive as Bonzai) for a year and just got tired of the poor quality surface models that required hours of fixing. Netfabb could almost always fix the stl, but then you still have a bad skb. The good thing about Sketchup is the ecosystem from the old days of free: plugins, tutorials, tips, textures, etc. The bad thing about Bonzai is the learning curve: there are many subtle command parameters that have major side effects if not set properly. And AutoDesSys has the best support I have ever experienced of any software or hardware product. Fast, responsible, knowledgeable, and truthful. So, Xperiment--lots in favor of both but Bonzai is certainly not a mess.

You might try Bonzai3d. A bit of a learning curve, but really productive with a true 3d engine. Produces much cleaner dae exports than Sketchup. And most of what you might do with sketchup plugins is builtin: evaluate and fix models, slice, rounded corners. It is a native app for both Mac and Windows.

Just downloaded Cura 13.10 last week and started printing. Wow, it's so amazing. The slicing speed (what slicing?) is fantastic. I hadn't printed anything for a while and only needed to make a test print before refining the object. So, I said what the heck I'll just use the quick printing normal quality option. Well, it was better than most of my tweaks of the advanced settings using 13.04. It's not a complicated object, but it has gaps to move across and one overhang of about an inch and a half. The overhang had a single strand that sagged and across the opening were a few strings which I pulled off with my fingers. I've attached a photo of the object--an iPhone case which I downloaded from Thingiverse and modified in Bonzai3d. Unfortunately, you can't see the hole with overhang as it is on the long side not shown in the photo. Bonzai3d is awesome. I have now given up on Sketchup. Despite an accessible UI, the underlying Sketchup engine is so poor and it's capabilities so limited that it is not worth the frustration. But, on to the question. How can I inspect the underlying settings made by the quick print UI choices in Cura? I would like these to be the departure for any future experimentation since they represent such good defaults. If I switch to advanced mode, do I see the settings used for the immediately prior print (using quick print)? Or do I see the previous choices (or defaults if no previous print) for the advanced parameters? I would love to see the default settings for the 3 quick print modes. Someone smart made those work really well.

Here is an update. I printed again at 200C, 40 mm/s, speed (nonprinting) down to 80 mm/s, the cube rotated 15 degrees off x alignment, wall thickness .8, and double skin OFF. The vertical ridge is pretty much gone. I can detect the merest trace of the ridge on the curved surface of the chamfered corner, but I know what I am looking for. It really isn't noticeable. Like noob, I changed too many things so I don't know what really is responsible for the improvement. I think, from watching the print, that is the combination of 15 degrees off axis and wall thickness of .8. Previously, I thought thicker walls would come out nicer so I tried 1.0, 1.1, and 1.2--all of which resulted in 3 (or 6 with double skinning) passes to do perimeter and loops. I think the odd number affected the order of doing the wall of the extruded inner cut (for the letter) and the outer wall. With 2 passes to create the walls, the order was altered and the outer perimeter was done before the inner perimeter. But, now, I have more vertical striations on the smooth vertical faces, which I read is caused by friction of the head pushing plastic along the surface causing the plastic to "bunch up". I am trying some cubes at different speeds and temperatures to see how to eliminate this. What's interesting is that the striations are very noticeable with black PLA and non-existent with silver PLA, which lays down incredibly smoothly at a wide variety of temperatures (205 to 220).

Will do. In just a few minutes.

Thank you for agreeing to look at this. Do you have any suggestions for how to send it? Perhaps private email? The gallery will not allow me to upload gcode or text. I have pasted a tiny portion here (even that seems to cause this page to hang). To everyone else, I apologize for the long post. Let me know if this is enough to diagnose the tool movement. http://pastebin.com/T6PfgGST

How do I reduce acceleration? I haven't seen a setting for that in Cura?

Thank you for the very thorough replies. As a I watch the print I believe the problem is that the interior surface (it's still the outside of a solid model, but what we would see as inside the cube because I am referring to the extruded hole for the letter) skin is drawn first for both loops/perimeters; then the head zips to the outside to do the loops/perimeter for the outside skin of the cube. It is at this point the head appears to either overshoot (for most settings) or undershoot (with some settings). I have tried all of loops/perimeter/infill, perimeter/loops/infill, and infill, loops, perimeter (that leaves out several) but none cured the problem. Tight belts all round reduced the height of the ridge. But, it remains. Illuminarti, your explanation is very clear. But, as you surmise, I have no control over which surface is laid down first, only which "ring" of the surface gets done first. But, the discussion has clarified something for me. Since the problem is a bit of overshoot when the head does a long move while not extruding, perhaps I need to slow down movement from 150mm/s to something slower. I'll try and report back. Would use of a different slicer give me more control over print order?

This is a problem that cropped up as I tightened my belts. With looser belts, I did not see the problem as severely, but several things may have been going on... I am printing letter blocks, 5cm cubes with a letter of the alphabet "extruded" all the way through the cube. To avoid a serious overhang problem, the cube is printed with the "hole" running vertically from bottom to top. Three of the vertical sides of the cube print very smoothly (I've used 210c and 220c and 30mm and 50mm speeds). One of the sides always has a distinct vertical ridge. After tightening and aligning belts all the way around, the ridge is only a very small bump or identation (depending on print order and orientation of the cube on the bed). But, it is a very noticeable visual defect as shown below in 2 examples. What you see (if you can see--it's not clear to me how to embed images that I previously uploaded in a gallery) is that the ridge on the vertical side always aligns with a vertex of the extruded 'L' in the center of the block. What is happening is that after the printer makes the loops/perimeter of the inner wall (the hole for the letter) the head shoots out to the outer wall to lay down the loops/perimeter for the outside of the cube. It is clearly overshooting or undershooting by a minute amount. How can I fix this? I have tried wall of .8mm (pretty good), 1mm (pretty bad--probably because not a multiple of .4mm), and 1.2mm (better than 1mm but not as good as .8mm). The problem would just go away completing if Cura would put down the loops and perimeter for the OUTSIDE before going to the INSIDE (followed by the infill). Sure, there might be a bit of a bump on the inside, but no one could see it. As for alignment, I have done a "hole cube" with rounded corners that pretty much prints perfectly--but it has only one surface. The problem with the letter cube is the movement of the print head from the inner vertical surface of the hole for the letter to the outer vertical surface. Any help would be much appreciated! Thanks, Lewis