How to make smooth surface

[3dprintinguser]

Hello, I am using a Stratasys uPrint SE Plus 3D printer. I tried to make a smooth curved surface but in both trials, I failed. The one on the left had support at the bottom (curved surface at the top during printing) while the one on the right in the photo (the shorter one due to earlier termination) was made upside down. That is, the curved surface was touching the support material. Is there any way to make the curved surface smooth? Is there a way to remove the strange lines. Stratasys mentioned that the pitch resolution is 0.254mm and as a result, there is not improvement in making the surface smooth. Do you guys have a way to make the surface smooth? Any way to remove the strange vertical lines? Also, Stratasys mentioned that the verticle lines were made due to starting and ending points. Any way to fix this issue? Thanks.

[wenganxiang]

The strange lines must show up when the printer is printing another circle. You can set the extruder to restract more filament when printing next circle.

[LambdaFF]

I agree with wenganxiang : add a systematic small retraction before starting and a wipe at the end. You can also tell your slicer to have random layer starting points : that way the defect should be less visible because it will not appear at the same point on each layer which makes it so obvious.

For the curved surface on top of the cylinder, a way you could try to improve it would be to turn the cylinder on the side.

[curious aardvark]

For the curved surface on top of the cylinder, a way you could try to improve it would be to turn the cylinder on the side.

lateral thinking there. Good idea :-)

Basically without printing with a higher resolution a shallow dome like that will always show layers.

The other answer is of course: fine grit sandpaper ;-)

The vertical lines are 'stitching' this is caused by the printer starting each layer at the same point.
You can remove these by having a random start point for each layer. That is slicer dependant though.
simplify3d has the option. No idea if your slicer does or not.

And again - sanding cloth/paper is your friend :-)

[Mjolinor]

Maybe this will help with your Stratasys.

Well maybe it would if I could upload it.

Are PDFs not allowed?

The file is 6.8 meg, is that too big. It doesn't work if I zip it either.

[curious aardvark]

you could email it to him.

[3dprintinguser]

Thanks for the replies. According to Stratasys, the vertical lines could be reduced/made less visible by having a random start point for each layer. However, they said that uPrint SE Plus's software Catalyst EX does not allow it. They mentioned a more expensive printer. As for not being able to create a smooth surface due to the low resolution on the z-axis, they also recommended another more expensive printer. Not very helpful.

curious aardvark : "simplify3d has the option. No idea if your slicer does or not." How useful is this software in terms of removing the strange vertical lines and making the surface smooth even the hardware does not allow a higher resolution n the z-axis? By "slicer", do you mean the Stratasys uPrint SE Plus in this case? I don't see this printer being listed in the compatibility list. For this kind of expensive printer, maybe only the software that comes with it will work?

All: Will the result gets worse if I make several printing at the same time? Can Acetone help to make the surface smooth and shinny? I plan to make larger smooth surfaces later this week.

Mjolinor : Do you mean pdf of the photo or pdf of the 3D model?

[Mjolinor]

I mean a Stratasys (I assume) PDF of common faults on prints and the things that cause them. PM me an email address and I will send it to you unless you already have it.

[3dprintinguser]

I turned the model by 90 degrees and printed it. The curved surface looks quit nice but now the circular edge looks ugly. There are several (not called horizontal) lines on the cylinder. So, I can only have either good looking curved surface or good looking cylinder edge?

Some of you suggested using sand papers. As far as I know, there are many types and fineness. Which ones should I use?

Are metal files better than sandpapers?

[curious aardvark]

best sanding CLOTH around is sold by woodturning supply companies. It goes down to 1200 grit - which is fine enough to hone an expensive folded steel kitchen knife.
Ideally you want to start with a coarse one - say around 160 and then use 400 or 600 and then finish off with 1200.
Used to do a fair bit of woodturning, so I've got loads of sanding cloth.

Acetone vapour will certainly help smooth it - IF it's abs.

Random start point will only help with vertical stitching lines on spheres and cylinders.

A slicer is the software that takes the cad file and turns it into 'slices' that are sent to the printer via gcode.
Most Popular ones: cura & slic3r - both free and both very good. Simplify3d is better - I think :-) And worth paying for.

One of the problem with buying expensive 'commercial' 3d printers is that they try and lock you down to their filament and software.
You'd probably be better off just buying a cheap non-commercial printer.
:-)