I am trying to print some 20mm ball shapes, the bottom is flat 10mm diameter.
I want to print these in ABS to use in swivel ball mounts and I have cut the bottom off and put a hole into it for a heat set nut.
So far the prints are failing mostly due to really bad surface on the bottom round area and some by detaching from the bed and the edges curling up.
Printing with 110c bed for 3 layers then 95c (I have found this works well for most of my ABS prints) Hotend at 245c.
I was printing at 80mm/s but am now trying at 55mm/s and I am trying with manual support all around the bottom half (using Simplify 3D)
My printer is in a heated chamber always around 40-50c.
Nozzle I have right now is .40 (I have some .35 and also have some .25 on the way). Layer height is .12mm also tried .15
I know I probably just need more trial tests with various settings but just wanted to see if anybody has any specific ideas to help print a ball shape.
I need it to be fairly smooth all over and the top is printing perfect but the bottom half is pretty ragged.
I guess I could split it in half and then glue back together but just thought I would ask as it seems like this should be possible as is.
I don’t know if they “fixed” it in recent versions of S3D, but increasing the infill overlap to 30-40% has helped for some prints in the past. Dense support layers and playing with the horizontal offset can also help. And slowing down the print should help also, maybe a perimeter underspeed close to 15 - 20 mm/s (try using two processes, slower for the problematic lower 25%)
For swivel balls, I’ve found that splitting and using a screw helps reinforce the strength… and easier to print. Smoothing the ball with sandpaper or just through articulation of the joint helped tremendously… wears down the “rough” spots created by the printer.
All of the above, and, since you say you need to cut the bottom of the ball of and make a hole for a heat set nut, why not design that into the ball itself?
I was playing around with a lampshade harp and made a ball that screws on to the top. I modeled the threads into the ball itself. I printed it on a raft upside down, with dense supports and it was about as good as if I had printed it right side up. Since you would have a flat bottom and smooth, cylindrical hole you should be able to print it with the flat side on the build plate (better adhesion) and you could dome the hole for the heatset nut so you wouldn’t need supports (though you possibly wouldn’t anyway depending on the size).
nce you say you need to cut the bottom of the ball of and make a hole for a heat set nut, why not design that into the ball itself?
Sorry I didn’t make this clear, I did model those features in. I was trying to convey that it has a flat bottom so sticking to the bed should not be an issue.
My attempt with support and slower turned out OK but still a bit rough on the bottom.
Good news is I went ahead and split the ball in 2 and it printed flawless and because it’s ABS just a few drops of acetone made it easy to fuse it back into a single ball again, I just had to sand the seam ever so slightly.
You need to BLAST the print with the fan, change it to at least 60-70% and make it come on almost immediately. Keep the bed temp high, 100-110 as you don’t want to print cracking due to the fan. That’s the only way to print large overhangs, You can program the fan to stop after the overhang if you want.
I also have the support minimum angle set to 10 degrees (perhaps unnecessary) and 25-30% fill.