3D Printing Tubes and Supports

[TheOneLasagna 0]

I was wondering if anyone could provide any tips or guidance when it comes to 3d printing tubes with supports. When designing the tubes, I quickly realized that they would have to print with supports inside them. I understand that it is easy to print tubes without supports if they are just straight, but if the tube includes curves, bends, twists, etc., how exactly would you remove them?  

 

Here's a curved tube that I need to print:

 

Supports would need to be created inside the tube toward the bottom, but how could I remove them once the print is completed?

 

[kmanstudios 1,120]

Dual extrusion with PVA supports?

[geert_2 557]

Does it have to be a circular tube? Or would a pentagon-shape also be okay? Or a triangle on top of a square, like a house-symbol? In that case, you could print it sideways, with the flat area towards the bottom, and the "roof" on top. I will try to insert a unicode symbol here, if the system allows it: ⌂

[TheOneLasagna 0]

On 4/8/2019 at 8:13 AM, geert_2 said:

Does it have to be a circular tube? Or would a pentagon-shape also be okay? Or a triangle on top of a square, like a house-symbol? In that case, you could print it sideways, with the flat area towards the bottom, and the "roof" on top. I will try to insert a unicode symbol here, if the system allows it: ⌂

 

On 4/8/2019 at 12:59 AM, kmanstudios said:

Dual extrusion with PVA supports?

Sorry for the late reply. I don't have a dual extrusion printer, so that can't be an option for me. It would also be a pain to go back into the model and change all of my tubes into a different shape, but I will consider it. Any more ideas? All I've been able to think of was maybe creating some kind of tool that can reach in the tube and remove the supports.

[geert_2 557]

You could try printing a short, straight section of a round tube sideways, for test. Print rather cold, and with max fan, or even with an additional desktop fan in front for fast cooling. The roof-section of the inside might look a bit like it has grapes hanging from the ceiling, but the canals should stay open. Try the concept on a short straight test piece first, to see how much the inner roof sags, and if this is still acceptable for you. PLA can usually bridge gaps quite well.

 

This is a test of a table model, with custom support structure. At the underside of the support structure, you see how much it sagged. The middle section overhang is 30mm long. But you can do better by printing colder.

 

So, if such an amount of sagging would still be acceptable to you, you can print it without internal supports.

 

The external part will need supports and good brim, otherwise it will fall over while printing. So you might consider some support structure similar to the pink support in the blue spring, and then cut that out later.

 

 

 

[TheOneLasagna 0]

 

 

 

 

 

 

 

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On 4/15/2019 at 6:44 AM, geert_2 said:

You could try printing a short, straight section of a round tube sideways, for test. Print rather cold, and with max fan, or even with an additional desktop fan in front for fast cooling. The roof-section of the inside might look a bit like it has grapes hanging from the ceiling, but the canals should stay open. Try the concept on a short straight test piece first, to see how much the inner roof sags, and if this is still acceptable for you. PLA can usually bridge gaps quite well.

 

This is a test of a table model, with custom support structure. At the underside of the support structure, you see how much it sagged. The middle section overhang is 30mm long. But you can do better by printing colder.

 

So, if such an amount of sagging would still be acceptable to you, you can print it without internal supports.

 

The external part will need supports and good brim, otherwise it will fall over while printing. So you might consider some support structure similar to the pink support in the blue spring, and then cut that out later.

 

 

 

 

 

 

I found an ok solution: I twisted some steel wire into a small cable using a power drill, and simply pushed that through the tube, making sure to twist it and break up the supports inside. However, I am still seeking a better solution. I will be sure to print out some smaller "test tubes" with different support settings and share the results.