What printing accuracy can I expect?
I've had my Mk4 running for a few weeks now, and am pleased with the speed and quality. Recently I ran a 40mm Calibration Cube and a Tollerance Test, just to see how accurately it's printing.
eSun PLA+ with the Mk4 Structural setting
Tollerance Test - Cleared at 0.2mm but parts were bound together at 0.1mm
40mm Calibration Cube - X=40.03mm Y=40.03mm X=40.00mm
I now feel that I can trust the dimensions, but have nothing to compare them against, and was looking for some feedback. Is this within expectations?
I presume you are using the standard 0.4mm nozzle.
Those are well within the expected range. The default extrusion width is 0.45mm so your cube variation is comfortably within a single extrusion track, your finest possible output. Expect lower accuracy on curves but if it drifts by more than 0.25mm you can probably dial up the accuracy of the mesh in your CAD application.
0.2mm tolerance is usually reliable for print-in-place mechanisms, about the tightest you can ever get with a 0.4mm nozzle and PLA is 0.125mm but that takes a lot of careful setting up - at that level the order in which parts are printed matters as does cooling so stay at 0.2mm if you can and expect to iterate prototypes for anything closer.
Cheerio,
RE: What printing accuracy can I expect?
Thanks Diem. It's good the hear that I'm within the expected parameters. 👍
RE: What printing accuracy can I expect?
I would say this is really good actually.
Formerly known on this forum as @fuchsr -- until all hell broke loose with the forum software...
RE:
I've spent countless hours on this as I mostly design and print functional parts. There an enormous amount of factors that go into the accuracy of your print, and in some respects it's a moving target.
Here's are just a few common things I've found that will affect accuracy in a 3D print. There are many more.
- Filament diameter (This can vary from roll to roll, and while many companies claim a +/-.02 accuracy, I've found most don't meet this.
- Material shrinkage. This varies based on materials and can be affected by infill type, percentage, # of perimeters, number of top and bottom layers, cooling, including the amount of time a layer has to cool before the next one is printed (I've found when printing a single part the final dimensions varied from when I printed multiple ones at the same time), ambient temperature etc.
The mechanical accuracy of the machine itself is really good, but when you bring all of those other variables in it gets much tougher.
Now to what extent this all matters depends on what your trying to print and what kind of tolerance your expect to achieve. I can tell you for fact that+/- .03mm will be very difficult to achieve and repeat unless you have at least the things I mentioned above dialed in.
RE:
To add to material shrinkage: the moment your model warps on your print bed, it's over, concerning accuracy.
as an example.