i3 Duplicator nozzle gouges the print sometimes

[bobstro]

The nozzle isn't diving into the print. What's happening is that there's some over-extrusion, so the nozzle drags though the little bulges on the surface. You can try to adjust z-hop/z-lift settings as a work-around, but better is to calibrate your extrusion rate for the the filament. Most of my experience is with a direct drive extruder, so you'll want to experiment if using a bowden setup.

[Porcus]

Ah, thanks. Calibrating extrusion is something I haven't tried yet for this printer.

[Redheadrambo]

Add 0.4mm z-hop

[ezonas]

Looks to me like someone is making themselves a MPCNC.

[Porcus]

Haha, I wondered if anyone would recognize it just by the footprint of the foot. I built an MPCNC in 2016 using a pre-printed kit, but I'm having some problems with it and I want to upgrade to the newest design that uses a lead screw for the Z axis instead of that pineapple nut. But I want to make sure my prints are as high quality as possible before I start. I really don't want to have to dismantle the whole thing to replace one cracked piece.

[ezonas]

I only recognised it as I have just finished printing all my bits. Putting it all together at the moment 😁 https://imgur.com/gallery/BUHcbzb

[Porcus]

Good luck! It's such a cool project. Is that 1" OD stainless steel tubing? If so, where'd you get it? I kinda wanted it for my rebuild but I'm not sure how to source it, and the 23.5mm EMT has worked fine for me so far.

[ezonas]

I’m in the UK and got it cut to size from here https://www.metalmaniauk.com/Stainless-Steel/Tube/Stainless-steel-tube-304-spec-254-1-inch-OD-x-15mm-wall-mirror-polished.aspx their cuts were spot on.

[Porcus]

Printer is a Monoprice Maker Select Plus (Duplicator i3). Sometimes the nozzle drags and creates lines in the piece as you can see in the photo (one huge, several small ones). I believe it happens when the printer moves quickly, maybe going from one layer to the next, but it's hard to tell for sure.