Hi, not sure how to explain this, but please have a look at this animated gif http://grasshopper3d.googlegroups.com/web/diff.gif?gda=yTya4zoAAABldvTupClBBQRPKkY0ld_QKGun8MxHdXDNm85G2wT1_EHcE07pV1nwQg62suKd4lf97daDQaep90o7AOpSKHW0&gsc=Swm1wxYAAADODYQlSjL_zp7xAGbszpmU57an5Fe8QJeePd7zpGv9tg
There you can see me selecting first a lofted cylinder, then some pipes and finally the boolean dif component. But as you see the boolean diff only occurs for the first of the pipes, and I could use some directions what to do to make all the pipes cut through the cylinder. /Lars
