First print layers density question

[CWAVE6K]

Hello.

I bought this software for use with my Lulzbot TAZ 5 printer yesterday, and it's been a tough haul getting this to do what I want. Don't get me wrong, I don't think there's anything wrong with the software, it looks wonderful... Think it's entirely settings, and am having a heck of a time with it.

I chose the "TAZ 4" for the printer I have, as the TAZ 5 isn't listed. Not much has changed on the two so figured I should be ok.

So, I tried to print something and even after hours of tinkering with the settings, I still have one major concern. That being the density of the print of the first layers.

Up to this point, I've been using Cura. Been very happy with it, however, not thrilled with their support structure. Find it very hard to remove. So, when I heard about this software, I thought I'd give it a try.

The problem that I'm having is that the first layers that are printed are more of a lattice than a solid layer. Take a look at these pictures, and you'll see what I mean. It seems to me that the amount of filament coming out of the nozzle is substantially less using Simplify3D than it is when I use Cura (ie: the thickness of the line deposited on the printbed).

This is printed using Simplify3D


This is printed using Cura


The finished printed model looks better printed using Simplify3D than it does in Cura, using the highest quality print settings. That having been said, I can't seem to get a nice tight bottom layer, and that's concerning me.

Has anyone got any thoughts on what settings I could change to make this happen?

Please HELP!!!

Thanks for your time...

[JoeJ]

It looks like your nozzle is too far away from the bed surface. Just decrease your Z-offset in the software. Click "edit process settings", choose the G-Code tab, and then decrease your G-Code offset for the Z-axis. For example, if you make it -0.05mm, that will move the nozzle 0.05mm closer to the surface. Keep decreasing the value until you fill in the gaps.

[CWAVE6K]

Thanks for your comment.

I will have a look at that, but given that Cura prints the first layer perfectly, I went in a different direction on my own with quite good results in the absence of any other comments.

Got thinking about it, and printing at high resolution was giving me a layer of .1mm The .1mm thick first layer didn't have a hope of providing adequate adhesion. Got reviewing some of the settings as well as found some good reference posts here (tip of the day entries) that better explained some of the settings in the Layers tab, and found that if I set the 1st layer height to 300 percent, 1st layer width of 100 percent, and 1st layer speed set to 50 percent I got better adhesion and coverage. The difference was remarkable. I'm now getting virtually the same results with my first layer print through Simplify3D as I was with Cura. Still some tweaking needed I think, but I'm VERY close.

I believe that Cura by default likely prints the first layer with a .3mm regardless of the resolution of the print (only an assumption here).

Anyways, I've got my TAZ5 printing rather nicely now with this setting. Like I said, still have a bit more work to do on the settings but the prints are coming out rather nice using Simplify3D now.

One thing that still isn't working as nicely in Simplify3D as it was in Cura was when the first layer prints, and the hotend is filling in the first layer, it doesn't seem to go all the way to the outline with the print

If you can see in the photo below, the infill on the first layer doesn't go all the way to the parts border. For a first layer, it still seems rather sparce...

This particular print is printing in .2mm layers, 150% first layer height, 200 percent first layer width and 50% first layer speed.



I feel I am getting closer however, but some tweaking is still going to be needed.

[jimc]

yes it doesnt go all the way to the edge because as joe said your bed gap is too big. fiddling with the first layer setting is unnecessary. how the first layer behaves is all in the gap. it has next to nothing to do with settings. cura may however be telling your printer to extrude a little more filament on the first layer which is why you dont get it with that. setting from slicer to slicer are not interchangeable. the way each one does the match is going to be a little different. adjust you bed gap so its a little tighter. move it .5mm closer at a time until its right.

[CWAVE6K]

Thanks guys (JoeJ and jimc) for the advice.

I'll work with your suggestions tomorrow and see if I can tighten things up!

Will report my findings and results as soon as I have something.

[moates]

Thanks guys (JoeJ and jimc) for the advice.

I'll work with your suggestions tomorrow and see if I can tighten things up!

Will report my findings and results as soon as I have something.

I have the same issue. All layers besides layer 1 have a very nice finish and density, but layer 1's lines aren't squished together enough.

I have:
- Leveled/trammed the bed
- Verified my Z0 height
- Tried different extrusion multipliers (this messes up layers higher than layer 1)
- Tried different layer 1 heights
- Tried different layer 1 widths

In all cases, the lines still are not connected as they should be.

[JoeJ]

If it's only your first layer that isn't filled in, you can pretty much guarantee that this is due to the position of your nozzle when printing the first layer. Otherwise, every other layer would not be filled in as well.

So an easy fix is to use the gcode z-axis offset (G-Code tab of FFF Settings). Just enter a value like -0.05. That will move the entire print 0.05mm closer to the build table which will help that first layer become more solid.

If you are printing at very fine layer heights (like 0.1mm) you may also want to use a larger first layer height like 300% so that your first layer is actually 0.3mm thick.

[moates]

If it's only your first layer that isn't filled in, you can pretty much guarantee that this is due to the position of your nozzle when printing the first layer. Otherwise, every other layer would not be filled in as well.

So an easy fix is to use the gcode z-axis offset (G-Code tab of FFF Settings). Just enter a value like -0.05. That will move the entire print 0.05mm closer to the build table which will help that first layer become more solid.

If you are printing at very fine layer heights (like 0.1mm) you may also want to use a larger first layer height like 300% so that your first layer is actually 0.3mm thick.

I'm printing at .3 mm layer heights. I'll give the nozzle closer to the bed a try, but I'm hesitant because the brim's height when measured is exactly .3 mm high at all points. This indicates to me that the bed is level, the height is right, and I should have dimensionally accurate parts as a result.

[Chadd]

I have the exact same issues with S3D. The problem is in the way that S3D deals with the first layer extrusion setting, for example.

You are printing a part at .2mm layer height and you set your first layer extrusion to 130%. Instead of putting 130% material into the space that 100% would have gone into S3D spreads the extrusion out and in turn will create voids between the extrusion. So it does the exact opposite of what other slicers do. Instead of forcing that extra material into the same space and creating a more dense first layer it creates a less dense first layer by creating the voids between the extrusions.

An easy way to see this is to play with the first layer settings and then look at a print preview, you will actually see the voids being created as you increase your first layer extrusion %.

I was about ready to pull my hair out because of this, I thought I had printer Z homing issues and battled it for months and it would force me to go back to using free slicers instead of the $150 S3D that I bought. How I finally figured out what was going on is that I always noticed that my brim would lay down perfectly as I expected but as soon as it started printing the actual part first layer it would look like crap and have voids between the extrusions. I then started playing with settings in S3D and looking at the first layer in the print preview and it was plain as day what was happening.

You can use a negative offset as others have mentioned but that causes other issues, including putting your print head too close to the glass when you print your brim. The best way to get a good part with the current settings in S3D is to set your first layer height to some % lower than your actual layer height "say 80%" and to set your first layer extrusion to 100%. As long as you have a good Z home and level bed this should get you a good part.

S3D has a lot of nice features but at the same time has a lot of rookie errors in it such as this. I really hope that they will fix the outstanding problems with the program in future updates but only time will tell.

[jimc]

hey chadd i know we were talking on the other forum about this. wanted to confirm something. when you set the first layer to 100% width your saying it shows normal extrusion in the print preview of the first layer BUT if you set the width to 150% then in the preview its showing you the same size extrusions but putting a space between the lines? if so can you post a factory file of a model you are seeing this problem with?