Printing Hubcaps  

RE:

I'm not sure about the strength when printed in this orientation. They would seem prone to cracking at the layer lines. And how do you plan on joining the halves? 

If I were in your shoes, I would print it laying down in 1 piece. Maybe the design would have to be changed. I am unsure what the inside and outside is. I would would need supports, but print it visible side up and you don't see the scars from the supports.

RE: Printing Hubcaps

Thanks. They are purely cosmetic, so don’t think the cracking would be an issue. 

RE: Printing Hubcaps

Looks like turning on "make overhangs printable" (on the whole hubcap) makes the whole center part in-filled, but actually uses less material and is faster. 

How fast will they travel?

I would be wary of printing and joining.  Wheels and wheel parts are subject to high stresses - think about it, a spot at the bottom of the wheel is stationary when in contact with the road but lifts and accelerates to double the vehicle speed as it goes over the top then decelerates to stationary again so at 50mph that's 0-100-0mph on every rotation.  OK hubs are subject to lower stresses than tyres but it's still something to consider.

Cheerio,

RE: Printing Hubcaps

Sorry, I should have included more info at the start. 

These are purely cosmetic on a station car prop. They won’t spin and will have no weight on them. They’ll be connected to a pvc pipe flange on the backside that will represent the axel. 

RE: Printing Hubcaps

A few questions and observations:

What are you planning to print them with? PLA is not a good choice. It will degrade rapidly. ASA is UV and weather resistant but hard to print and emits fumes while printing. ASA can be glued with Acetone. Nylon or Polycarbonate are stronger. These are going to be subjected to strong rotational forces and can come apart and fly off, possibly injuring someone else.

That orientation is not great for printing. It has no base to hold it on the print bed, and the thin profile will almost surely warp. Tall and thin is very hard to print. Most likely it will warp, come loose, and wind up a spaghetti monster. I agree that you should print it flat, with supports and the side you don't see down, so the remains of the supports are not visible and can be cleaned up as necessary. One piece would certainly be better. Prusa slicer does have some split and join options but I have had better luck with a fancy puzzle cut someone came up with in openscad. I really like this work, but it is not simple:

https://calbryant.uk/blog/3d-printing-giant-things-with-a-python-jigsaw-generator/

You need some thickness to get them to fit and have to modify the parameters for your model.

Regards,

Mark