K8400 Exterior print quality (RESOLVED)

Vertex 3D Printer Vertex - Issues while printing
1

Hey everyone,

I picked up a Vertex last week and got it fully assembled and functioning now. This is my second 3D printer, the first being a Mini Fabrikator which I’ve been using for almost a year now. The assembly was non-eventful and quite enjoyable. I printed a pair of setup jigs on my Mini Fabrikator to hold the X & Y axis rods parallel to the drive rods during the belt setup, and printed a couple of clips to take the excess slack out of the X-axis belts. The motion seems smooth enough however I have noticed a couple of things.

  1. I went through the following extruder calibration procedure… I removed the Bowden tube and aligned the end of the filament with the edge of the extruder body. I then used Repetier to advance the filament 100mm. The filament advanced considerably more than that so I adjusted the E-steps/mm value in the firmware to ~150 as per others suggestions. I went back and advanced the filament again and the result was 100mm of filament extruded. Success! Although when I went back to printing I noticed 2 things. 1- The “Load Filament” procedure no longer worked as the filament never reached the hot-end. 2- When I went to print a test piece, it seemed woefully under-extruded. I set the E-steps/mm in the firmware back to 200 and the prints are once again looking like there is sufficient extrusion . (within reason) This seems odd to me but it seems to be working at 200 even though it is not “properly calibrated”.

  2. The sides of the printed test piece are not exactly the quality that I have been experiencing with my Mini Fab. When I printed a 20mm x 20mm test piece, the X & Y dimensions came out to approximately 20.5 each and the sides showed considerable “banding” or perhaps “blockiness” is a better description. The included pictures show the phenomenon I am experiencing.

The blue piece was printed on my Mini Fabrikator using ESUN PLA. Although the sides show the tell-tale 3D printed ridges, each layer is well aligned and exhibits a high quality finish (IMO).

The yellow piece was printed on my Vertex, again using ESUN PLA. The sides of this print look considerably worse. There doesn’t seem to be any layer shifting, and I don’t think that there are any skipped steps, but the exterior finish is not what I’ve become used to. I’m not sure if the culprit is vibration related, extrusion related, or travel related. The Mini Fab has more or less always just worked, so I’m not really sure what to check here.

Both pieces were printed at the same speed (20mm/s) with the exterior perimeter being printed at 70% speed. (Although the blue piece was sliced using Slic3r, and the yellow was sliced using Cura and printed via SD card.) Any suggestions are very much appreciated.

Cheers,

Andrew



2

It seems there’s a bit of z-wobble check the spacing between the Z-rod and the stepper motor.
Inside the coupler there should be a bit of space.

3

Thanks VEL337,

I spent many hours last night trudging through the first 9-10 pages of this sub-forum looking for answers and had a few things I wanted to try when I woke up this morning.

As per your suggestion I adjusted the Z-axis coupler first and also dropped the temperature to 190 degrees. Voila!!! Success…

This is the type of print quality that I was expecting… or at least hoping for!

My latest print (Gecko) shows a very dramatic (totally gone now) reduction in the layer problem.

I can’t wait to get me some HIPS for printing support structures…

4

Just a quick follow up…

I’ve had this printer working for a week now, and with the exception of the initial hiccup described above, it’s been an incredibly positive experience! After quickly adjusting the z-axis coupler, the print quality improved quite a bit. I’ve done 5 or 6 projects now, and I’m absolutely blown away by the results print quality wise. (And I’m only printing at 0.15mm layer depth.)

This printer is very impressive, especially given the price. I haven’t owned, used, or even seen prints from a substantially more expensive machine, but I can’t imagine the print quality of a $1,500+$3,000+ machine being substantially better. (At least within fused-filament machines.)

I’ve even been playing around with HIPS in the second extruder for support, and have had excellent results with that so far. I haven’t had a chance to dissolve the support structures yet, but the print itself came out flawless.

Very impressed with this machine. I guess my only disappointment so far is that it’s quite noisy compared to my Mini Fabrikator.

As a side note, my brother was thinking of getting a ROBO 3D, but after seeing one of my prints, he’ll probably get one of these.

Way to go Velleman!