Boolean Union problem

 From:  Michael Gibson
426.4 In reply to 426.1 
Hi Matt, thanks, I'm glad you like MoI!

The reason for the union failure is that the cylinders inside the wheels are floating just a little bit in front of the back plane of the main wheel part, they aren't touching - here is a zoomed-in view from the top of one of those wheels:

You can see the dashed lines for the edge of the cylinder and the back plane, there is a bit of space in between them, the cylinder is floating in front of the back face a bit.

To make the union work, these objects must be touching each other - and it is usually not a bad idea to make them actually stick through each other a bit instead of only exactly touch, but they must at least be touching.

It also looks like there is a bit of a slant to the cylinder piece's face - maybe this was done as an extrusion of a very slightly off-axis circle? It might be a good idea to draw a new cylinder in there to get a really regular end on it.

It looks like you're having some fun creating stuff!

- Michael