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Gerrardh

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Everything posted by Gerrardh

  1. Found the problem - it was 'Adaptive Layers'.
  2. Hi all, I'm trying to diagnose print issues on a custom built printer, and I noticed that some areas of my print appear to be over-extruded, so I've been trying to find a way to visualise the calculated line cross-section. I found that I can visualise 'Flow' in cura, which is about as close as I can get. The problem is that flow is proportional to speed, so a fast section has a higher flow than areas of lower speed - I really need a visualisation that's independent of speed. Anyway - what I noticed, is that as my layer count increase, so does my flow rate, even though the requested speed and line width are fixed. Why is this? I noticed on my other printer this doesn't happen, so there must be a setting in Cura that I've modified. Any ideas? Flow: Speed: Line Width: Overall Part - notice that the dark red sections are consistent with the over-extruded sections on my prints. Thanks in Advance.
  3. I'm a mechanical engineer - when we do FEA we get a results view similar to Cura's preview. That is, view of the model, heat mapped with a colour scale that indicates different values - be it stress, deflection or in Curas case, travel speed, flow rates etc. One thing that helps immensely in FEA programs is a 'Cursor Probe' - a function that allows us to a) hover over model geometry, and have a display that shows the value on that part of the model and b) place 'flags' at various places of the model so they can compare the values at different locations. Is anyone aware of a function or plug-in that allows users to do this?
  4. Thanks for replying. You might be right about keeping the jerk the same = fewer lines of code, but the problem exists during a print path, so there's no travel involved (refer to attached video). my maximum resolution setting is 0.5mm with maximum deviation 0.025mm. Regards
  5. Hi All, I've built a large CoreXY 3D Printer and I'm debugging problems that I've observed. The machine is running Duet2 Wifi board, slicing in Cura 4.7. I notice that the print head frequently stops and starts on curved surfaces - just momentary pauses, but it's enough to leave behind a small blob - problem is that it does it very frequently so the prints look awful. I've researched a bunch of suggestion and none seem to fit the description all that well. Here are a few observations: The blobs DON'T occur in consistent locations - e.g. a vertical seam, edge or otherwise. Suggesting that the problem is not related to geometry (seam in faces, curve radii, etc). The board is 32bit, so can handle much more complex code without buffer issues. Very simple geometry (straight lines) doesn't have this problem. Looking back over the G-Code for an arbitrary layer, I was looking for changes in the feed rate (assuming that the slicer is introducing momentary speed changes). I noticed groups of M566, G1, M566 commands which momentarily halve the jerk, and speed, before accelerating it again. To be clear- I have no way of testing whether this code relates to movement, but it looks suspicious. The problem didn't occur on my first 2 layers - only higher layers. The first few layers have lower speed, so speed could be a factor some how. Jerk is 12mm/s for print, 24 for travel. Accel is 600 for print and 1200 for travel. The link below shows a video of the problem - the first few seconds (while printing the visible surface) is the most obvious. Any suggestions?
  6. So I decided I would use Change at Z post process to add a lower speed for this particular layer as a work around, after checking the gcode in Cura, I needed to restart. After re-starting, the problem doesn't exist. I now have bridge settings enabled, and the line direction is across the part - not along it. I guess the bug should be updated to "sometimes"? I definitely wasn't working earlier, but now it is. So weird!
  7. FYI, This setting now exists in Cura as "Overhanging wall speed" under the "Experimental" Section.
  8. I've seen others complain about this (in 2019), but I haven't seen bug raised yet - hence the post. Enabling "Bridge settings" defaults to the bridge taking the longest path from point to point, and this is not configurable. I've attached a series of images - I've changed the values for the top and bottom line directions (0 and 90°), I've tried changing the top/bottom line pattern, and changing the orientation of the part - none of these work - as you can see in the images the lines run the full length of the part in each case. When I disable bridge settings the lines run across the part as they should. Please change the default behaviour and/or expose the bridge direction variable for the user to set as desired. Thanks
  9. Request: Very quick suggestion - please make the print settings for multiple extruders have one column per extruder (two extruders, two columns), so the user can quickly compare settings between extruders. Currently state: There is one tab in settings per extruder - two extruders, two tabs. Currently the user needs to switch tabs (and therefore hide the settings for the first extruder) in order to view settings for a second extruder.
  10. That's what I think... while the print head is moving slowly, the fan is blowing on the extruded filament to help it cool... Once it's cool it's strong enough to prevent sagging... There are still limits of course... Each layer needs to be supported somewhat by the layer below, but a single thread of filament WILL support some small cantilevered overhang with minimum sagging.
  11. Hi All, Not sure where to post suggestions, so I'll leave this here - please let me know if it belongs somewhere else. I'd like to suggest a setting that allows the travel speed to decrease (user settable) in areas where the overhang gets above a certain value. I found with my printer, if I left the travel speed at the usual setting (40-50mm/sec) then my overhang tests would only get about 50-55 deg, but if I dropped the speed to about 10mm/s then I could get results much closer to 75-80deg overhang meaning I could print much more complex parts with less support material. Unfortunately printing a whole model (especially a large one) at 10mm/s is out of the question... So it would be super cool if Cura could allow me to reduce the travel speed immediately above areas (for say... 4 or 5 layers) that have overhangs above a certain value in much the same way as supports are added now if overhangs are over a certain value... Hope I'm not the only one who'd find this helpful. Regards
  12. Hi All, I've been struggling with a blockage somewhere in the filament path for a few weeks now - I've tried a whole bunch of things, but I'm not having any luck. Tonight I pulled the bowden tube out, with the intention of cleaning the hot end and cooling block, but I found that the end of the bowden tube had some melted filament pushed back up inside about 5mm or so. I remember when I re-installed it last time after pulling it apart, I pushed the bowden tube back into the cooling block quite a way - until it stopped. I now realise that it doesn't stop until it touches the nozzle which can't be right. So the question is... how far should I install the bowden tube into the cooling block? I'm guessing it should go down to about the heat break, but I'm not really sure if that's enough to prevent melted filament finding its way back up into the bowden tube. Any suggestions?
  13. It's the educated guess I'm looking for... I've exhausted all my experience, so looking for suggestions... I agree that the top layer LOOKS too thin, but it's the same thickness I usually use... 0.6mm, I only did that print with 10% infill, but I just re-did this same print with the same top layer thickness, but with 20% infill and it's turned out OK... not brilliant, but OK... I hadn't considered print temperature... I've been printing at 200degC on all my filaments, but I'll try dropping it a few deg to see if there's a difference. Thanks for the advice...
  14. Hi All, I have a CR10S that is all standard - save for a few 3D printed tweaks. I've just spent the better part of a 3 day weekend trying to print a few relatively uncomplicated parts, but facing non-stop issues along the way. Issue number one, was nozzle blockage - I suspect the nozzle was just old, but that may be related to my current, and currently unsolved problem. After the fist completed print of the weekend, I came home today to find that the parts were complete except for nasty looking surfaces. There appears to be two separate issues - firstly the top surface (only) of the round parts is broken and opened in places, secondly the vertical edges of the taller two parts has a nasty case of stringing... This is the first time I've seen either of these problems, and I've successfully printed from the same models before... For what it's worth, I'm generally pretty happy with the printer - I've put the better part of 3kg of filament through it since I've had it, and the prints are usually really good... I've replaced the nozzle, cleaned the hot end, checked the bowden tube for restriction, re-checked the calibration of the extruder, tightened the extruder clamp... What have I missed? Thanks in advanced.
  15. Hi All, EDIT: I'm not sure how to explain why this happened, but I had a problem, then through a change in order of events, I've resolved it... Skip to the EDIT below to see the steps I took... Original post, immediately below this. I've made it about 10hrs through a 30-odd hour print, only to find that some parts which were suppose to have printed as supports haven't... My model is made up of several sub-models, each with slightly different settings. I applied the settings through the "Per model settings" menu, selected a model that I need to be support - select "Print as Support", then merge the models to position the sub-models where they belong, then slice the finished model. Unfortunately Cura simply omits the regions that should be printed as support, and instead leaves me with a hole in the model. For what it's worth, the "Print as Support" option works fine if you don't merge models Now I need to revert back to Cura 3.2 to start this print over again. EDIT: I've just tried the same steps in 3.2 again, and its ALSO not working! Which is really odd - when I open an old project that I've saved, the "Print as support" option is working fine - but it doesn't work for a new project. So I tried opening the old project, in Cura 3.3.1, re-sliced and it works... I tried deleting all the models from that old project in Cura 3.3.1, inserting new models, tweaking settings and slicing - that worked. Next, I tried merging the models in Cura 3.3.1, then slicing - NOW IT'S WORKING?! Now.. For a sanity check, I'll try a new project in Cura 3.3.1 Load models in, tweak settings, then slice... And I get an "Unable to slice" warning... Weird... Re-positioned the model on the build plate to re-enable the "Prepare" button, then re-slice the AND IT WORKS... Conclusion: Always the same models and settings, tried in Cura 3.3.1 and 3.2, some times it works, sometimes it doesn't... I can't figure it out... Regards
  16. Hi, Thanks for the reply. I had done a bunch of research but hadn't found that thread... nevertheless I think it's a slightly different workflow. It looks like they're printing with distinct prints, one for each colour. I want one print with multiple filament changes... I was mostly worried about clashing the nozzle into the presiously printed parts, that's why I took this approach, however it doesn't look like it affected them. I've already split my model into multiple parts and just edited the code to replace extruder changes with filament changes. I had briefly looked at combing but I understood it to be something different... I've currently got it set to "all" I think I'll try "No skin". Thanks for the advice!
  17. Hi all, I've spent the last day or so trying to figure out how I could use print a multi material part on a single extruder by adding a filament change line where it would have changed filaments with a multi extruder printer... my aim is to print a client's colour logo into the first layer of a part... I figured it out with a combination of setting multiple extruders then replacing gcode with the M600 code. Anyway... it was to no avail. Because while printing one color the print head travels across the blank bed and leaves a trail of colored filament... so my logo would end up looking great except for these travel artifacts... What I'd like to see is that the print head only travels over printed regions on the first layer... Any idea how this might be achieved? Thanks in advance.
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