splitting a cylinder into two easy to assemble parts

[Anonymous]

Hello everyone,

I'm pretty new to fusion 360 and 3D printing so hopefully I'm not asking a stupid question.
I have this cannon cylinder that fits horizontally on the plate but not vertically.
The fusion slicer does not seem to provide the best of supports. For that reason I think it would be easier if i could print the cannon vertically instead of horizontally.

The idea of this design is that a ball 7cm in diameter will be propelled by the two wheels spinning at high speed and the cannon will help with the aiming. In order to do so the surface inside the cannon must be as smooth and straight as possible (aside from the rifling which may or may not be useless).

My question is how could i split this cannon in such a way that two parts of it will fit snugly into each other and minimize the speed loss at the junction point?
Basically i want to split the body but leave one half with a slot and the other half with a sort of peg that fits into the slot. However it all has  to happen along the surface of the cylinder. 

[etfrench · Accepted solution]

1. Create a plane to use as a splitting tool.
2. Split the cylinder.
3. Create a sketch on the plane.
4. Project the cylinder into the sketch.
5. Draw three or four tabs.
6. Extrude the tabs using a two direction extrude. Join the tabs to one of the cylinder pieces.
7. Print.
8. Glue cylinders together.  If printed in ABS you can use acetone to both glue the pieces together and to smooth them.

[chrisplyler]

Without some kind of doodle or something, I have no idea how you envision the split. Are you asking how to model a design you have in mind? Or are you asking us how it should be designed?

PS - I'm pretty sure the rifling will be completely useless acting on a ball projectile. A ball doesn't really need spin stabilization anyway. Even if it did, the fit required for the rifling to have the desired effect, while being acceptable when the projectile is being propelled by explosive cylinder pressures, will likely just make the ball stick in the barrel when it's only being propelled by a very, very momentary contact (and just a tangential, single point contact on each side at that). So you're going to target a loose fit, which means the ball will just be rolling along the bottom of the barrel and not contacting the top, which in turn means that the rifling is really just a crooked slot that is going to make the ball roll side to side as it rolls lengthwise down the barrel.

[MoshiurRashid]

You should create a plane for splitting. then other jobs.

[TheCADWhisperer]

File>Export and the Attach your *.f3d file here if you can't figure it out.

[Anonymous]

Thanks, that was really straightforward.

[Anonymous]

Thanks for the recommendations on the rifling. I was also skeptical that it would achieve anything but my coworker insisted it was a good idea. If it does end up being a problem I'll remove it.

[chrisplyler]

Sounds like your coworker is capable of the observation that shooty things often have rifling, and thinking that therefore it must have a purpose.

Sounds like your coworker is NOT capable of actually considering the whys and the hows of that purpose, and whether it is applicable in any particular case.