MF Pegasus Print Quality Issues

**FDM_Process** · 11-05-2015, 10:32 AM

Well that makes more sense because that was how I had my solidoodle setup. However, I only switched to a SSR because my original heated bed died and I replaced it with a more powerful one.

I'm not seeing how this would cause a z-banding issue like the one imaged above, especially near the top of the print where the heated bed would have absolutely no bearing on the actual print.

**printbus** · 11-05-2015, 11:24 AM

Originally Posted by FDM_Process

Well that makes more sense because that was how I had my solidoodle setup. However, I only switched to a SSR because my original heated bed died and I replaced it with a more powerful one.

I'm not seeing how this would cause a z-banding issue like the one imaged above, especially near the top of the print where the heated bed would have absolutely no bearing on the actual print.

People have proven that the heat bed toggling on and off causes the print surface to move up and down with the toggling of the heater. With bang-bang control, the slow toggling can lead to artifacts through the entire print as the bed surface moves up and down. Going PID with an SSR allows the toggling to be fast enough that the up and down movement is negligible.

**BLKKROW** · 11-05-2015, 08:01 PM

Originally Posted by FDM_Process

Well that makes more sense because that was how I had my solidoodle setup. However, I only switched to a SSR because my original heated bed died and I replaced it with a more powerful one.

I'm not seeing how this would cause a z-banding issue like the one imaged above, especially near the top of the print where the heated bed would have absolutely no bearing on the actual print.

It doesn't matter if your print is 10mm or 10X10^10mm's tall. If the base (Heatbed) fluctuates up and down by 1-2mm's then the whole print is moved up and down 1-2mm's.

**FDM_Process** · 11-06-2015, 08:38 AM

Okay, well let's test this. Since I'm printing in PLA anyway I'll just turn the heated bed off and see what happens. I will report back.

**tsteever** · 11-06-2015, 09:23 AM

I am curious to see. Adding the SSR helped my prints come out nicer. I didn't have the banding to that degree however. I did at first. The firmware provided from Colin had me over extruding quite a bit. Only once I had my machine calibrated better and then adding the SSR was I happy with the prints.

I think in this case adding the SSR will help. If you still have banding issues (The may be smaller) you might have a extruder calibration issue too. I still chase that number all the time. It is why i have modified my firmware so that the knob on my display adjusts the extruder multiplier instead of the speed while printing.

**FDM_Process** · 11-06-2015, 09:48 AM

I'm about halfway through printing the "okay" model with the heated bed off and the banding is to the same extent (I will post a picture when it's finished). I will calibrate the extruder again but I think I have it pretty dialed in and I'll also see if I can't get a small video of the carriage moving up and down to visualize whatever amount of z-wobble I have.

I'm at a loss here because the very first prints came out rather well with little to no sign of banding at all.

**FDM_Process** · 11-06-2015, 12:45 PM

Alright, printed with the heatbed off. No change. I raised the height of the z to the top and homed it and watched for wobble in the carriage assembly and it looked pretty good. I checked for mechanical tightness which was also good. I calibrated my extrusion settings, also good. I am now trying Simply3D instead of Repetier/Slic3r and seeing how that goes.

Here is a picture of the old print and print with the heated bed off, side by side. Old print on the left, current on the right.

~

**tsteever** · 11-06-2015, 01:51 PM

Wow that is some crazy banding. I really thought the heated would be the issue. It was for me. What layer height are you printing at? I am not 100% on the construction of the pegasus, does it use 5mm z rods?

**tsteever** · 11-06-2015, 01:54 PM

Also, I now am using matter control and am getting much nicer slices than with Slic3r and cura. It doesn't have as many settings as slic3r but the prints are much better. It is free and may be a good alternative to paying for S3d. If you have already paid for s3d then use that. it is expensive!

**misquamacus** · 11-06-2015, 03:57 PM

That actually might be a layer height/model resolution issue. Try printing that tower test object again, the one you initially had good results with and see if it comes out like this.