12 November 2025

Concentrate on one thing at a time?

I am currently looking at 'Slicer Flow Calibration' which is the next step on Martin's list after the Baseline Print. The only real problem with the first test cube was a little bit of gapping in the top surface, which was pointed out as being due to low volume of extrusion. The magic fix in Cura is to up the flow rate a little so I jumped in with my size tens and tried 110% which when printed was a little high, then I realised that of cause the 'Baseline Print' code was NOT created by my copy of Cura, so MY starting point should have been to run my own code for a 'Baseline print'.

So I'm using the 'Slicer Flow Calibration' without any boost to the flow and the printer is doing an excellent job of printing a 0.4mm thick wall 30 mm heigh. Had some fun trying to locate the digital calipers which I'd only just put down, but the 110% print was 0.49mm thick so lets see if the next one is 0.44mm which suggests I actually need a little less extruded, and that makes sense given the little extra blobs that appear from time to time. Once I get closer to 0.4mm I can run my own test cube g-code and see how the top surface looks, but things are all very clean anyway.

One thing I have spotted is that adding the 'Skirt' around the print allows a number of things to be sorted. It clears out any remaining old colour in the head which is a start, but also it allows me to tweak the height as the Z axis switch does not seem to be reliably repeatable. That or there is a problem with missing pulses between the two z axis motors. I've tracked down an example of adding a belt between the two stepper motors to lock them together and the necessary parts are in my eBay basket. Makes perfect sense to me that this will add to repeatability, but I will also check the next step in the sequence and verify if I can the setting of the stepper motor drivers. I'm more used to the nice beefy ones driving Nema23 motors with 3 or 4 amps so the miniature ones on the controller are going to be fun. Playing with the firmware on that card is another area that will be interesting. Tweaking the firmware to correct the flow rate makes more sense going forward.

I've also been looking at the glass plate option for the bed given just how clean I can get things, a switch to the 0.2mm nozzle may well be practical but do I actually need the masking tape layer at all? It gives a little patterning to the base which is not a problem with practical things like the spool holders, but may be a problem with the larger models I'm looking to print.

Update ... the second cube print gave 0.45mm, so now trying 95% to see how that does. The wall IS very stable as flat, so cooling is obviously crossed off the list. Patterning in the finish still needs addressing, but I also need to sort belt tension before reviewing it.