First Layer Refinement - Go Away Distinct Filament Lines

[webdad]

Assembled an Original Prusa i3 a couple weeks ago as my initial introduction to 3d Printing and have been having a blast since then. Started with Cura, and after reading comments about Simpifly3D, decided to invest in it. Had it about a week and in general, print quality is on par, or better than Cura, with one exception - first layer printing.

I've been focusing in PLA for the time being, using some Inland PLA, since MicroCenter is close by.

I've had great success with Cura for printing a set of vases, basically right out of the box - load and print - beautiful.

The wide variety of settings in Simplify3D obviously required a little more rigor, and I downloaded some Original Prusa i3 profiles to start with.

Generally, when printing from gcode generated by Simplify3D, the first layer shows a very distinct pattern for the filament with very narrow separation between the strands, shown on the V2 / V3 test blocks I'm using pictured below.



I've been adjusting:

• FirstLayerHeightPercentage
• OutlineOverlapPercentage
• firstlayerwidthpercentage
• fanspeed - layer 1 = 0, layer 5 = 100
• extruder multiplier between 0.95 and 1.05, with 1.0 being the best (v2) above

None of the above combinations that I've used have been able to get significantly better than the "V2" block pictured above. Most other combinations result in the individual filament strands separating completely, or in part, from the second layer, like the "V3" block above.

I have been able to make the filament strands on the first layer "fatter" and stable with:

<firstLayerWidthPercentage>200</firstLayerWidthPercentage>
<fanSpeed>
<setpoint layer="1" speed="0"/>
<setpoint layer="4" speed="100"/>
</fanSpeed>

But, the individual strands are still visible.

Being very new to 3D printing, I was just wondering if the bottom layer could be tuned to look more like to the top layer, which always turns out very nicely.

I've attached FFF exports for:

• V2
• V3 - first layer 'stranding'
• V5 - fatter layer

FYI - Tracking the myriad variety of setting changes has been a learning experience to say the least. The best success I've had is by exporting the FFF profile for every test print and then using an XML difference tool - https://www.diffnow.com/ to identify the detailed differences.

It would be really nice if Simplify3D did a better job of letting you start with an existing name when saving new profiles, or generating print files, like it does when exporting an FFF. Even better yet, be able to show a report or detail on the difference between 2 profiles.

Any thoughts or guidance would be greatly appreciated. I've gone through the print quality guide, but haven't been able to get this put to bed.

Thanks

Ray

[CompoundCarl]

It looks like your nozzle is start a tiny bit too high above the bed. They have that identical issue explained in their print quality section: https://www.simplify3d.com/support/prin ... to-the-bed

Read the second option in that section, specifically about adjust the Z-axis offset

[webdad]

Excellent idea! I'll give that a shot. One of my other failed cubes was when I spent a fair amount of time because the head wasn't laying anything down when it started, and the extruder was clicking and not feeding any filament. I thought the extruder was jammed, but it was always able to load new filament and extrude the change.

I finally let it run for a couple layers and as the head rose just a couple layers, it started extruding and the clicking went away. That "failed" cube had a bottom as smooth as glass.

I subsequently re-leveled the bed and I was back in business. I should have put 2 and 2 together.

As a result of that I was thinking of using a thinner sheet of paper to do the leveling the next time, but the z offset is soo much simpler.

Thank you!

[webdad]

I tried a number of gradual z-offset setting changes, but they don't seem to be making a significant difference in the first layer, although other layers do seem to be getting squished.

Here is an extreme z-offset of -0.40 (white) compared with the baseline (Orange). You can see that the first layer isn't too much different between the two.



The layers immediately above the first layer are now bulging out



So, this isn't having the impact I was hoping for.

Any thoughts or suggestions?

Thanks again for your help.

[jimc]

dont use the z offset in s3d. not that it doesnt work but having that set in your saved processes is going to screw things up down the road when you foret to adjust or change it. you'll load a process and not realize there is something set there and it will mess the print up. just keep it at zero and the first layer height to 100% then adjust the z gap on your printer so its right. correcting misadjustment on the hardware side by using the software is more like a bandaid.

[KC_703]

I do this all the time through the Z-offset setting... only for .1-.3 increments though. Anything beyond that and I'd consider adjusting the endstop.

Speaking of Z-endstops, its best to get that right before tweaking with the Z-offset. I use the Z-offset so often, that its part of my routine to check this setting as I modify the profile. If its not a habit, then I suggest getting the endstop correct so you're not reliant on the software setting.