Printing a Semi-Circular object - Ideas?

[Tetraodon]

Scrap that - I think it *might* be able to bridge it, but it's printing it in that V shape which makes no sense for bridging - it's trying to extrude out into thin air. The result wasn't that pretty. I can make an "eh" looking result if I use a line of support down the middle - but is there any way to get the program to bridge it like it normally would (between two points, lengthways) rather than in this weird V format?

[KC_703]

Well... glad the supports may not be needed for much of the cylinder. The top of the arch has always been a bit weird for me also... especially with smaller nozzle diameters and higher resolution layer heights.

A single support column down the length of the cylinder may be the only way to cure it... I'd probably go with a 3-5mm support "wall" down the middle of the cylinder. Make sure to orient the support perpindicular to the length of the cylinder.

Making the top of the arch flat on the inside may allow the printer to bridge better.

Another option to print without supports is to put the cylinder on its side so the bottom is a vertical wall. It minimizes the messy top portion of the arch. It may be a bit tricky to print the half cylinder on its side... If you can, add manual support "tabs" on the bottom face. This will create a bit more surface area than the single edge to tack / bond the cylinder to the bed surface. Make the tabs small enough so they're easy to break off.

Red block creates more surface area than the single edge. Remove from part when done.

Hope that helps!

[Tetraodon]

Hmm - will look at making that middle arch flat rather than a V shape and whether that makes a difference!

I'm a little bit nervous about printing it on its side due to the lack of surface area - the ABS is already pretty prone to warping. If I put some supports at the top arch, it may work - as it's closed on one end that's definitely preferable to placing supports inside the tube where they're hard to remove.

[DarthRevan]

We had a sudden case of weird print adhesion, but it's back to normal now and I could do a test print.

The lines in the middle are the remains of the supports - left of it had supports, the right had no supports. Supports were 5%, 5 dense layers of 15%, 0.35 horizontal offset from part, 1 upper and lower vertical separation layer.





So supports definitely aren't needed except for the top two angles

Unfortunately (something I've been experiencing with lots of prints) it's still pretty messy at one point - any thoughts on printing this cleaner? (file attached)

I'm agreeing with JoeJ.

The best way to eliminate that nasty top surface is to print it standing up. If you're planning to mass produce these, perhaps a printer with a larger build volume is able to be incorporated into your budget.

[bray.christopher]

Unfortunately they're a wee bit taller than what my printer will print - I intend on making ones larger also, as this is one of the smaller sizes - so I think I may have to work out a second interlocking system to print each part in two parts (making 4 parts total).

That sucks. Vertical is the way to go. Is that any chance that you could add small hollow bosses on the inside or outside that you could slide a rod through to connect multiple pieces? Then it could be as long as you want.

[bbinnard]

Your part loads easily into the build volume of my delta style printer's build area (210 mm radius and 320 mm height). One reason I got this type of printer was to be able to make taller objects.

[bray.christopher]

Like that?