Closed Bodies Union

I have two closed poly surfaces according to rhino and i want to join both of these solid geometries into one solid body.
One is hull and other is rudder.
Any help please…

The command Boolean Union

nope its not working tried several times

Without a .3dm file with the geometry (strongly preferred) or at least some good illustrations of the geometry it is difficult to provide anything other than random guesses about why BooleanUnion does not work.

What happens if Intersect is used on the hull and rudder? Do the hull and rudder intersect? Is the result a closed or open curve?


As David mentioned above, use the intersect command, then examine the resulting curves to see the problems with your boolean. Common problems are incomplete intersections, self intersections, and parts that simply don’t overlap.

following is the file i am having issue
Hull+Rudder Closed and Rudder joined at aft perpendicular.3dm (1.2 MB)

The model is in meters.
Bounding box dimensions of the hull and rudder = 7.716, 1.020, 0.744 meters
Absolute tolerance is 0.1.
The absolute tolerance is too large.

Use a tolerance setting equal to or one order of magnitude tighter than (1/10 of) the best tolerance you can hold through your manufacturing process – or one order of magnitude tighter than your smallest modeled detail, whichever is smaller.

For an object of this size the absolute tolerance should be 0.001 or smaller. 0.0001 would be preferable.
Change the absolute tolerance and BooleanUnion will work.

Knowing how to select the absolute tolerance is essential to success using Rhino.

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It was initially the issue that started when i was trying to close that igs file… it was showing naked edges so to eleminate that issue is searched the best option was to increase the tolerance which i did and my hull joined in one closed polysurface… so keeping in mind i did the same for the rudder geometry as well but in the end of joining process it was not joining through any command

Hull + Rudder Final only Union Remaining.3dm (1.5 MB)
Following is the file I have set the tolerance as well but still union fails

Did a union Thanks very much problem was of tolerance.