I am having difficulties with Boolean union that do not seem to make sense. I am working on a model that is bilaterally symmetric, where on one side of the model parts will union just fine, while on the other side parts fail or even get deleted after supposedly successful union. I also get error messages on the side where the union seems to be successful.
This is the section of the model I am working on. It has taken me a couple of hours to finally successfully boolean all the parts together.
I want to union everything together so I can then Mirror three times and end up with this.
On the right side I get the following message every time I try to union the long pipes with the arcs.
When I click OK this then seems to result in a successful union. Other times I get the following message, even though the parts I try to union are identical to parts I have previously completed a successful union with.
Whenever I tried to union one particular part on the left side (the second arc from the right with the long pipe at the bottom) the pipe gets deleted. However, if I boolean another arc with the pipe at the bottom first and then try to union that second arc, it works. The same thing happens when I later try to union the third arc to previously unioned parts. But if I union the third arc to the bottom pipe first this does not happen. When I do unions on the right side none of this happens. There I only get the error message dialog boxes as shown above.
I then tried to many different ways of the order in which I tried to union parts together. After many tries and many boolean fails, I finally found a sequence that resulted in getting all the parts together.
What may be the reason that many boolean unions failed and finally one was successful?
I have uploaded the file in question before the final successful boolean union, so people can take a look at this if they wish.
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