Print quality subpar, photo included

Hi Everyone,

My name is Pete and I am brand new here.

Quick background… I would consider myself a very amateur user of 3d printers. I use them for prototyping designs of products I manufacture based upon a patent I hold. My company is Reflo Ltd, if anyone wants to know. I am from the Cleveland, Ohio area.

I originally had a wood framed Flashforge. Worked fine for getting basic prototypes together to test function. However, anything bigger than the print area had to made in sections and glued up.

I recently purchased a Lulbot Taz 6. Love that I can print all of my currents needs in one piece… however I am having some issues with the quality of print, even at finer resolutions.

My STL file was produced at a extremely high resolution, since most of my prints are cylindrical and I want to avoid facets along the face.

I am using Inland PLA, sold at Microcenter where I purchased the Taz 6 about 2 weeks ago.

The issue I am having is that my prints are showing steps between layers and an ugly run along what I assume is the end of path in the cylindrical print.

I was printing with the shell setting at 15mm (to ensure a completely solid fill by going way beyond the thickness of my print) I had infill set at 0. Perhaps this is the source of my problems? I did just change it to 1.5mm shell and 20% infill to see if there are notable changes.

I hope that you don’t mind that I chose to come here instead of print a dozen different items with various settings to work out bugs. I figured there is no sense in trying to reinvent the wheel.

I have attached a pic of my last print to illustrate the issue. I’m not sure what other setting would be relevant but I can share whatever is needed. I am just not sure what to share.

I would hope to be able to produce a high quality print for a presentation without a ton of hand work after printing.

Much more cooling fan, tighten your idler, use the default print profiles as a starting point, set “print starting points and infill before exterior perimeter first” on or whatever cura calls it, white pla is terrible to learn with because it contains titanium dioxide and heats wierd. Cylinders are difficult to dial a new printer in on. Go grab calibration objects to identify the issues from thingiverse and adjust accordingly.

Ok, I’ve followed your advice and with the preset configuration this was the result. no improvement. See pic of new piece.

Not only is there this terrible overlap but the fact that the layers are not aligning is a huge problem.

You are showing less wall voids. That’s an improvement. Next up, you need to adjust your extrusion by printing calibration objects and adjusting accordingly. A hollow walled cylender is the hardest possible thing to print, and you cannot do so unless your printer is dialed in. Some of that is factory, some of that is settings, but a big portion of that is fillament diameter and fillament profile (dan speed, print temperature, number of shells, etc.) For example, the default fillament diameter setting is 2.85mm. If your fillament actually measures 2.95mm in diameter on average, you will be overextruding on every layer by 0.04 percent. You are either way overextruding, or way under extruding. Measure the wall thickness at the thin point and the thickest point. Whichever one is closest to the actual diameter you were trying to print is the direction you need to adjust.

You aren’t looking at Z banding or Z wobble here, because it’s not consistant and it doesn’t match up with the leadscrew threads. You are looking at inconsistant extrusion leading to layers of various thickness, which is causing the divots and thick sections you are seeing. The more i’m looking at it, the more I think you might be underextruding a bit, and getting thinner towards the end of the wall, then catching up on layer changes. But it could be the other way around.

You need to check settings and print calibration objects to figure out exactly what is going on. Print a 40mm calibration cube, does it end up exactly 40mm on all sides after cooling? Run a 100mm extrusion test. Mark fillament exactly 110m from the top of the extruder and slowly extrude 100mm of it. Does the mark end up exactly 10mm from the top of the extruder? if not, your e-steps are off. Run overhang tests, run bridging tests. Print a benchy or 4. Until you have it dialed in, don’t bother trying to print another hollow wall cyelnder, it won’t work and it’s not due to the hardware.

The areas where the rings of layers seem depressed are also raised on the inside of the cylinder. So it’s as thought the layers are shifting in and out occasionally.

Interestingly, the side of the cylinder directly opposite of the z band is damned near perfect.

I don’t see how over/under extruding would be the culprit since it is a shift of the alignment, not a bulging or contraction of layer width.

Could also be loose belts.

I hate to be the guy who asks advice and never posts a solution when he finds it.

So here is what I have deduced… on my own. Nobody seems to have been able to offer anything solid otherwise.

The cylinder I was printing has about 2mm thick walls (actually .06"). I had set Cura to various wall/shell thicknesses to effect a solid wall. the results were garbage.

I finally dialed back my shell thickness to .5mm (my nozzle size) and with 20% infill my print is coming out much better.

I am puzzled why I can’t simply produce a solid and clean print but it could be the filament, the software or the hardware… I don’t know. SO the workaround seems to be to make sure your inner and outer shells don’t overlap.

Interestingly, I printed a test cylinder of just 1mm thick and no contours and it printed perfectly.

You’ll notice on the original photos, The worst portion is to the right side of the Z band… that has been a constant. Even on the print I am doing now, which is MUCH improved, any defects are still in that same area… just to the right of the z band.

So noted. I won’t bother trying to help you with any future questions you might post here then.

You offered a bunch of suggestions that didn’t improve the issue. not to be unthankful but I was simply making the point. I do thank you for being the only one who tried.

And I meant that in a larger sense as I’ve gotten no help on this issue from Lulzbot support either, etc.

So, apologies for hurting your feelings. Didn’t mean to.