Boolean Union is failing.

Next
 From:  Rudy
1292.1 
Dear All,
Rudy here.

The boolean union in my 3d model does NOT occur.
I want to boolean union the head with shank of the ring. It does NOT happen.
Any idea why?
See attachment

Thank you in advance
Rudy
Attachments:

  Reply Reply More Options
Post Options
Reply as PM Reply as PM
Print Print
Mark as unread Mark as unread
Relationship Relationship
IP Logged

Previous
Next
 From:  Rudy
1292.2 In reply to 1292.1 
Dear All,
I got it.
I made a mistake in building my head....started with the inside of it. But I should have started with the outside of it.
Taking care of,
Thanks Rudy
  Reply Reply More Options
Post Options
Reply as PM Reply as PM
Print Print
Mark as unread Mark as unread
Relationship Relationship
IP Logged

Previous
Next
 From:  Michael Gibson
1292.3 In reply to 1292.1 
Hi Rudy, there is an area where your 2 pieces have a lot of surfaces that are "coincident" - that is that they have surfaces that are running exactly over top of each other:



This kind of situation tends to make things much more difficult for the boolean calculation code.

If possible you want to have objects that sort of punch more fully through each other rather than having a lot of overlapping surface areas.

In this case, if you can trim off a little bit of the end of your ring, that will get it less confused and make the boolean union work.

What I did was to draw a line here:



Then I used Mirror to make a mirror image of that line on the other side. Then select the ring and run Construct / Boolean / Difference to slice the ring with those 2 lines, this will slice off the ends a little bit so that there is not so much overlapping area with your head piece.

Then you can select the little cut-off ends and delete them (to select them you may want to use a window selection where you click in an open area and then drag to make a selection rectangle).

With this bit of surgery now the 2 pieces look like this:



There is still some overlapping area along the bottom, but it is now a much smaller amount than before. With it set up like this, then the boolean union is able to complete successfully.

I have attached the unioned result here as ring_unioned.zip

Sometimes it may be necessary to do this kind of tweaking when the booleans are having difficulty. Reducing the number of edges and surfaces that are running right through or over top of each other makes things a lot easier for the calculation.

- Michael

  Reply Reply More Options
Post Options
Reply as PM Reply as PM
Print Print
Mark as unread Mark as unread
Relationship Relationship
IP Logged

Previous
Next
 From:  Michael Gibson
1292.4 In reply to 1292.2 
Hi Rudy,

> I got it.
> I made a mistake in building my head....started with the inside of it.
> But I should have started with the outside of it.

Yup, with the outside first it would generally be a cleaner approach because it would have less intersecting pieces at the end.

Things get more complicated when there are a greater number of pieces simultaneously involved with a boolean. Also it can easily happen that your result model contains fragments of a bunch of pieces all joined together - it is just better in general to have a smaller number of pieces when possible.

In an ideal world you wouldn't have to worry about this, but ....

- Michael
  Reply Reply More Options
Post Options
Reply as PM Reply as PM
Print Print
Mark as unread Mark as unread
Relationship Relationship
IP Logged

Previous
 From:  Rudy
1292.5 In reply to 1292.4 
Michael,
I do not know how to thank you. It is so valuable to me all this tutoring.

I really appreciate all the effort and time you spend with me.

Rudy
  Reply Reply More Options
Post Options
Reply as PM Reply as PM
Print Print
Mark as unread Mark as unread
Relationship Relationship
IP Logged
 

Reply to All Reply to All