Newbie Confusing Himself

[lbarger]

I have a Rostock V2 with stock nozzle. According to SMC the standard nozzle is 0.5mm. My software seems to be configured for 0.4mm nozzle. I don't recall changing this setting and it does not seem to be covered in the standard startup of the build manual. My parts seem to print OK, except I seem to have a little too much material on the final layer and possibly the first layers as well. I'm going back through the calibration process as I am about to print my first part for work which needs to be dimensionally accurate with well stacked layers. Should I change my software to be 0.5mm nozzle? I do not have a set of pin gauges to independently confirm the actual diameter of the nozzle.

Also, I would appreciate it if anyone could point to any rules of thumb for 3d printing such as min/max layer thickness based on nozzle diameter.

[teoman]

If it is stock chang it to .5

Layer no larger than nozzle/2


Use .2mm layers for now.

[Polygonhell]

The generally accepted rule is Extrusion Width/ layer Height should be at least 1.5.
For most plastics you should set extrusion width to more or less match the nozzle size or a small ammount bigger. The one exception to this from my experience is PET seems to want a wider extrusion width to print reliably, because it seems to be less able to stretch.
So by the 1.5 rule, your can print 0.5/1.5 reliably with a 0.5 nozzle. However it's a little more complicated than that In practice, extrusion width doesn't directly correlate to nozzle size, and you can quite happily print with extrusion widths in the 0.7 range on a 0.5 nozzle, so you can actually print taller layers than that math implies.
Stick to 0.2-0.3 with a 0.5 nozzle and extrusion width around 0.55 and you'll be fine.
If your top layer looks like it has too much plastic, you really need to do an extruder calibration using a single wall test print, IMO it's the single biggest factor in print quality, there is a sticky post on how I do it in the V1 Rostock forum.

[lbarger]

If it is stock chang it to .5

Layer no larger than nozzle/2


Use .2mm layers for now.

Thanks for the information. Does this include the first layer? The defaults are .35mm for first layer and .2mm for all other layers. The object I am wanting to print is larger than any of the little toys I've printed so far and I seem to be having some adhesion issues, thus the recalibration. I'm also using the Aquanet hairspray which seemed to do better with my 5" diameter part than my first attempts with the disappearing purple Elmers.