The bed is too close for the first layer. For a first print, it turned out fabulous!
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It sure did! Congratulations.
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Just a note of thanks to those of you who took time to consider my questions and even post answers and encouragement. I really appreciate the help. This has been a long frustrating build with duplicate purchases of several electronic components and reprints and just not much time to make it work. There are still so many things still left to do (enclose print area, enclose controller area, mount LCD, mount RPI, turn on camera, mount camera, make soft feet, make bed drop pads, secure print trolley wiring, etc.), but it is at least somewhat useful now and the purpose it was built was to reprint the MPCNC parts I cracked from heavy use this summer. Based on my first bency print, this is totally possible now. Thank you!
Curious about 3d printing calibration for dimensional accuracy:
printed a 1"x1"x1" cube (25.4 mm x 25.4 mm x 25.4 mm) of PLA at 205 °C with a 0.4 mm nozzle and a step height of 0.2 mm.
X = 25.38 mm
Y = 25.77 mm
Z = 25.59 mm
Is that within what should be considered acceptable tolerance?
Possible sources of dimensional inaccuracies:
- overextrusion
- excessive heat and flow/squish
- some other minor setup issue.
Thoughts?
Only at 60 mm/s. There is no shaper sensor on it, so it isn’t up to speed yet. How fast should it go? I’m basically using stock generic slicer settings. If it is accurate at slow speed it should translate to faster speeds. Intuitively… But, it probably needs to be tuned for specific speeds?
Generic slicer settings don’t translate to different printers. My best settings for PLA - 30mm/s for the first layer, then 200 for infills/inner layers, 500mm/s top and bottom (with acceleration 3000 it does not get to that speed unless there are long runs), 80-100 for outer wall. All of that after setting linear advance, input shaping, correct geometry and extrusion multiplying
Your cube is good but you can get within 0.2mm accuracy. Print bigger model, like 100x100. This will give you a better picture if culprit is steps per mm vs extrusion multiplying factor
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I looked at your settings and then put in these:
and it looks like this:
as opposed to the one at 60 mm/s that looks like this:
There is definitely some resonance around the Y on the faster one, but it did it.
Wondering if it will print a benchy with these settings…
Hard to see on the yellow but if you get ringing on faster speeds either reduce acceleration or use input shaping (which is great and does not require any additional hardware). Also make sure linear advance is also set to the correct value. Every printer is different
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+1 for this. Ended up wasting >400g of filament on a Core that was wrong height. Cause was I didn’t use larger dimensions to calibrate Z correctly.
Really you need to print something big. So if you 10X that size is the error now 250.38mm or is it 253.8 or worse?
I do this by printing large rectangles and face them different ways depending on what I want to test. No sense printing a giant cube if you can do it with two rectangles.
my measurement caliper only goes to 6" , so the printer is working on a 150 mm square frame that is 10 mm high and 10 mm thick. That might be a bit taller than needed, but should give an idea of the error for x and y. Then it will print a 5 mm x 5 mm tower 350 mm tall… because it can.
I see a darth vader helmet in my future.
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Yeah, so that isn’t supposed to do that:
THEN she says, “How much would it cost for you to just buy one that works?”
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In face in my case she said - “Just buy one that works!!” 
You wouldn’t get to work on it then!! Heresy.
Well in my case she also asked several times- “why did you buy the kit, can’t you buy them already finished?”
Sometimes I just HAVE to put my foot down!
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… And there’s more : In disassembling, I took the extruder off and proceeded to lose one of the bearings. Luckily having kept the box for it, each part was labelled in the info leaflet, so now we just get to wait on Amazon and run the cnc I guess.
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Bummer.
Where was the hotend leaking from when it started squirting plastic?