I don't know if I've come to the right place,

3D Printing
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I don’t know if I’ve come to the right place, but I want to know a little bit more about 3d printing. I am looking to make a simple sphere by 3D printing it. It seems simple to make from a standard 3D printer, but I don’t know.
If it is simple and economical, I will look into purchasing a printer. I have to test a sphere in its application first before I purchase one though.
Here are the specs:

  1. Outside diameter will be 145mm (tight tolerance).
  2. Inside diameter doesn’t matter but the wall thickness must be strong enough to withstand small bumps or drops without breaking or denting.
  3. Material must be a strong, hard, smooth plastic.
  4. Material must be a matte white.
  5. Sphere must be solid. If a hole is remaining from the printing process (I’m not sure how the process works, one hole is acceptable below 10mm.

Is this a good use of a 3d printer? Where could I have a prototype made? How much would it cost?

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  1. Outside diameter will be 145mm (tight tolerance).

With a properly calibrated printer, you can achieve this specification.

Even if I tell my modeling software to print at 145 mm, it might not be that figure, but then I tell the software to make it 144.5 and I get the desired result.

  1. Inside diameter doesn’t matter but the wall thickness must be strong enough to withstand small bumps or drops without breaking or denting.

You’d want a few mm thickness, depending on number 3 below.

  1. Material must be a strong, hard, smooth plastic.

ABS qualifies, but the printing process creates layer lines which can be reduced/removed with post processing.
Using SLS printing from a third party (shapeways, for example) would allow the item to be constructed of nylon and would have a somewhat grainy but smooth surface, and could be matte white as noted in 4.

  1. Material must be a matte white.

Many colors are available, but some post processing results in a shiny surface. That could be bead blasted, soda blasted or sand blasted (think air eraser product) for matte finish.

  1. Sphere must be solid. If a hole is remaining from the printing process (I’m not sure how the process works, one hole is acceptable below 10mm.

A solid sphere does not have a wall thickness. I think you mean the surface should be continuous. If that’s correct, SLS will require to have a “drain hole” for the un-sintered powder. A 10 mm hole is much larger than required, but you’d want to check the provider’s specifications.

I have a yet-to-be completed SLS printer, but the low power laser requires black nylon powder for better energy absorption. The surface of items created with this specific printer are like very fine sandpaper. You can feel the roughness, but appearance is quite clean. Commercial services have much more expensive printers and can offer various colors in SLS form.

For an FFF printer, aka FDM printer, some of your requirements may be challenging to accomplish, when taking all of them as a whole.

Post processing of an FDM printed part would also involve removing the necessary print supports and cleaning the surfaces to which they were attached.

A commercial SLS service is likely your best first option.

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Without giving too much detail, the specs have to be exact for software recognition purposes.

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@Fred_U Thanks Fred! That’s exactly the info I was looking for.

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Could make a mold (two halves) and use rotational casting

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@Jeff_DeMaagd I thought that might be a possibility too. Use an FDM and post processing to get a smooth sphere, then use silicone mold making material to cover each half, then ordinary resin in the manner you reference should generate a less expensive model than using SLS. I’ve done something similar and expect to do so again. It’s relatively easy and quite fun too.