Build Your Own SLA/SLS

Hi there once again, been making progress with the LittleRP and have yet another question.

As can be seen in the picture below on the panels between the lines there are some artifacts, on the stl this area is perfectly still so I don't understand why these "triangles" appear! This only happens on the Z axis, on the x/y flat panels are flat.

Thanks for your help.

What orientation are you printing in? If you can change the orientation, you can tell if it's a slicing issue or some other type of Z artifacting.

O the first picture it was printed vertical (90º) from the left to the right of the piece. On the second piece it was printed slightly to one side (115º) and the "artifacts" are very similar!

This refers to the second picture:

If you look at the individual slice png files can you see this step? Are you using anti-aliasing?

You know what they say, "Don't fix it, feature it!"

Just kidding. The "exactness" of the lines makes me think it's a problem in the export of the file to a STL as STLs are a collection of triangles.

I agree with NC42...seems like an STL issue. if you post the STl file I can take a look for you.

Thanks for the replies,

I'm using 1.5 antialiasing, is this relevant?

I also thought about the STL but nothing appears when the surfaces are facing with the x/y axis!!

I'm attaching the STL of the planes anyway, maybe there's something I'm missing!

I'm going to agree with Dangre.

I looked at the STL and it looks perfect. Each panel is composed of two triangles so there is no problem there.

What I see when slicing with standard settings and looking through the slices in the slice viewer is that the X,Y resolution is too low to make the walls perfectly flat. If the walls were situated to where they were perfectly parallel to the Z axis then it would work fine. But the model is slightly skewed and so the pixels make a stair stepping effect. If you look at it in slice view and slowly scroll through the slices you can see the pixels stair steps moving left and right along the panels in the exact pattern that you see on your prints.

pixels, pixels, pixels.

try printing at a smaller scale and see what happens, or rotate it a few degrees around the Z axis. I'm certain the artifacts disappear when you rotate around z (not 90 degrees tho..some odd number)

Exactly, we are printing pixels here... Rotating say 45 degrees around the Z-axis would be my solution. Maybe increasing anti-aliasing?
Looking at the individual slice files helps resolve many questions why prints do what they do. I once was pulling my hair out on why a feature was not printing and when I looked at the slice images I realized why (not enough pixels exposing one feature).
Dan