Odd issue with top layers/roof

[astr0lite]

First I would like to say how much I love Simplify3D! I have been using it for many moons with no issues however after upgrading to the latest version I finally have a reason to post

I use Simplify3D with a Lulzbot Taz 3. I have added a downward fan (like the Taz 4 has) and an enclosure for printing ABS...otherwise the printer is stock.

The Taz has given me wonderful prints with Simplify3D until I upgraded to 2.2 Now I am seeing gaps/holes in the top layers/shells. With ABS (all I have printed with) and no downward fan I have printed all the way up to 50% infill and 6 top shells and still have holes.

Any ideas?

Thanks!

[jimc]

Be sure random infill placement is unchecked and the holes are usually a sign that your temp is too high and or extrusion multiplier is a too low. In 2.2 there is also an option to set a soecific print speed for the top layers. Slowing them down a little worked great on my machine but perhaps its having the opposite effect on yours.

[Memnarch1113]

I've had a lot of trouble with top layers on my Ultimaker, and when printing at .1 mm in general. A basic fix is to simply add more solid top layers. Even if some mess up, the top should look good. This is especially important when changing the default layer height: When you lower layer hight, make sure to increase the number of solid top layers to keep a constant solid top layer thickness. IE, if you go from .2mm to .1, you should double your top layers

[astr0lite]

Thanks for the info!

I have tried all the way up to 6 top shells (this is all at .20 layer height) and it was better but still not great. Previously I always used 3-4 top shells and it was perfect...same thing with the temps...previous to the software change this exact printer with the same filament printed the top layers great I did check some old gcode and the extrusion multiplier was 1 as it is in the new software. I suppose I will end up just going back to the old version since it worked better for me.

[jimc]

Did you notice what the infill looked like? Was it all broken and flaws in it as well? Broken infill will result in broken top surfaces like that. If your infill is broken then as i said check to make sure the random infill placement is off. If that is off then be sure sparse infill is set to 1 then bump up your infill width to maybe 150% or more. When it gets close to printing the top layers take notice of the infill again. It should be a nice solid grid.

[SteveGodreau]

Thanks for the info!

I have tried all the way up to 6 top shells (this is all at .20 layer height) and it was better but still not great. Previously I always used 3-4 top shells and it was perfect...same thing with the temps...previous to the software change this exact printer with the same filament printed the top layers great I did check some old gcode and the extrusion multiplier was 1 as it is in the new software. I suppose I will end up just going back to the old version since it worked better for me.

I am having the same exact problem with PLA and ABS printing at .3mm and now at 5 top layers it's ridiculous. I hate to say it but I NEVER have this problem on my MakerBot and/or using the MakerBot slicer. I have tried everything with over extrusion, infill width, higher % infill seriously running out of ideas