Rough finish when printing cylinders

Hi friends

after cleaning the mirrors in my form1 + has returned to life.

always with excellent finishes, but always with the same problem when printing cylinders.

I only design PET bottles. then it is essential for me to have excellent finishes in the cylinders.

always the part that is closest to the resin tank is a rough finish.

the closest to the resin tank has finished rough on the outside and the far side has finished rough inside.

anyone know why?

Is there any play in the resin tray left to right (assuming the long supports are on the hinge side)?
Thinking that you might be seeing a slight shift as the machine peels each layer.
Check but don’t yank hard on the tray. Also check and make sure the build platform isn’t loose. There is a screw on top that you can tighten a little at a time so the clamp will snug down.

no, everything is ok, actually the machine is new.
the tanks resine and the build platform dont have any play.
is very frustrating for me this rough finish

the sema result in other part

Wow! That’s a pretty impressive part — especially when all assembled. We’ve seen some issues with similar artifacts like this before, and truth be told, they can be tough to get rid of entirely.

As a first step, I would try printing the bottle at a slightly greater incline. You might end up with some supports making contact on the outer (or inner) surfaces, but those may be less work to clean up than the entire surface. Essentially, the verticality of the print may be creating some artifacts that build up over time.

I would also contact our support team and see about getting instructions to clean your mirrors. A persistent bit of dust could be contributing to the issue, but it’s hard to know.


in fact I just cleaned the mirrors with the instructions you sent me (thanks for the instructions)

I’ll try a higher inclination and publishes the results.

I try with another bottle this night

Sounds good — keep us posted. I’d definitely print with the larger part on the hinge side of the build platform, if you’re not doing that already.


actually the large part is in the hinge side :smiley:

I noticed that you have the bottle opening towards the supports, doubt that is the cause for the surface finish problems but you will have a bottle full of resin that will need to be emptied, try turning it the other way so it empties as it prints?

The pattern you have I had before but it was the build platform being slightly loose.

You should feel the clamp snug down. Even though the platform doesn’t seem to move it might under pressure.

Tighten the flathead screw 1/8 of a turn at a time. When you lock it down you should notice the difference as you press the lever down.

I just printed a piece that is 4" tall and it has no edge flaws at all.

hi @KenCitron, the position of the bottle don’t cause a full of resin bottle. actually the bottle is empty. because in the bottom of the bottle always is open. in the final 50 layes the laser close the bottle, so never have a full of resine bottle.


the second test is equal, I have a rough surface finish :frowning:

I still think you have a tiny bit of play on the build platform.
I also noticed you have lots of bubbles, using the scraper I completely empty the tank and strain the resin between prints. Gives me a chance to scrape off any light fogging that might be from the resin sitting and a chance to inspect the tank and mirror.

I just completed a print and the sides are perfect other than a few specs from the supports.
I had one other print that was tall, not a cylinder but opposite sides had the same pattern you have on the bottle and it was the build platform being slightly loose.

Has anyone else notice this with the build platform loosening up over time?

If you are still having one side rougher than the other I would do a laser-spot test. It is probably not projecting a round dot.

@KenCitron no, i’m very sure of that. i dont have any play in the build platform… i use a completely new build platform and i check the screw adjustment and in the build platform and is ok. the tank resine and the resine are completely new!

I cleaning the mirrors before to print this particular part. and the laser test result is very good.

I think I found the secret for a good surface finish in cylinders or bottles. the previous test I have a 2.5mm thickness in the bottle. and the result is very bad. i changed the thickness to 1.5mm and the result is completely different!! almost perfect!

Amazing difference! I’m guessing if you were to print thicker walls then you would probably have to stand the bottle up more?

maybe. sound very logic.
now i try to polishing these bottles. i have a new dremel and cotton discs!

I have similar issues with cylinders. Even with our really super expensive ABS machine we have axis-of-movement artifacts on occasion. This is sort of what these look like. I wonder if its a vibration thing with the laser / galvo or just lack of tolerance with it in the first place.

Mine aren’t exactly symmetric. More like 4 o’clock and 8 o’clock.

I’d note that, one of the very first things I printed when my machine came back form service was a cylinder and it had these artifacts… so it was ‘factory spec’ sans FedEx ‘break in’ and I still saw these.