Problem with quality - lines


I have problems with lines on every print I make.
Firt of all - we have horizontal small lines (layers) in every print we make - at the 0,25 print speed. We haven’t managed to make a really smooth, nice print yet - donno if we cannot make proper project - or those lines are the maximum quality of print that formlabs2 can do.
Second thing - those vertical bold lines. They started to appear lately - and are in every print we make. They are deep enough to sense them with your finger.
We use hight temp rersin. We also cleaned glass and resin tank.

Vertical lines are almost always something in the optical path like dust. This can be on the glass under the build tray, on the build tray, or inside the machine.

I always try blowing dust off first. wet cleaning is a last resort because it takes some time to get all of the streaks cleaned off.

Yes, FredB is right. The vertical lines could mean that something is in the optical path.

It looks like this object is quite thin, is that right? It might be that the horizontal lines are because it doesn’t have enough support across that thin dimension. That could cause it to move back and forth a tiny bit between layers.

The automatic orientation would have tipped this back quite a bit so that the supports could be spread out over a larger area. That would have braced the model better to prevent that type of motion. Is there a reason you didn’t use the orientation PreForm calculated?

We cannot use orientations calculated in program cause we make sport medals, orders and coins and we need supports always on the side of print. We need surfaces to be as smooth as posible - supports just destroy surfaces.
About thickness - this print from the photo is sth about 4,5mm - 5,5mm - and that thickness is minimum for those kind of prints. But we’ve managed to print smaller ones - even 1mm - and formlabs didnt have any problems :).
As I said - we use hight temp resin, but I’ve seen in this forum ppls works - in some grey resin - and lvl of details and smoothness is incredible O_O. With our resin - we are faaar away from that awesomness,
We will cleen the glass again - and try different orientation of model - but I just dont see how to avoid horizontal lines - they appear always - even if we didnt have the formlabs in our company and the file was printed in the shop by someone else.

Your orientation is too steep so you don’t have enough supports to keep the print from flexing as it prints.

When you print parts like that do it in 2 halves, front and back then you can adhere them together with some raw resin and a laser pointer. If the medallion is really thick >.125" you may need to chuck it in a post cure for a while. This is one the reasons I use clear resin.

For medallion, coins and other flat objects keeping the part at 45-60 face up works best for me.

That will solve the stripes that are parallel to the build platform.

As for the big stripes, I can’t tell if that is part of the design. If not then there is a chance your model has co-planer faces. This means objects are sitting on the surface of another object.

If your software is unable to boolean union those shapes for what ever reason then slightly intersect the geomtries by at least double the layer thickness then export out an obj file and bring that in. (always export obj files as trinagles only for best results)

If you need to print coins vertically they need to be oriented perpendicular to the wiper. This gives more support during the peel cycle.

Also, for the thicker parts try to orient the supports in triangle patterns across the side of the coin. This will add some stability.

If you put some supports on the back it will print better and since it’s a flat surface it should be pretty easy to sand smooth

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