ISOGEN confused with +Z+X piping

Posted by: Michael_Fletcher

ISOGEN confused with +Z+X piping - 07/08/15 04:36 PM

Question if you use ISOGEN much. Whenever you have piping that visually overlaps in the default isometric view, ISOGEN gets finicky.

E.G. model a C shape in CAESAR in the +X, then -Y, then -X directions. Now rotate that model -45° in the Y. All three lines now visually overlap in the default isometric view.

In my case, I had several tap connections coming out on the vertical leg, which also visually overlapped.

When I ran ISOGEN, the top leg was drawn off at a completely off-kilter angle than the bottom leg.
Posted by: Michael_Fletcher

Re: ISOGEN confused with +Z+X piping - 07/09/15 09:08 AM

Attached is a screenshot in default southeast isometric, front view, and resultant ISO.

Has anyone run into this before? Come up with a workable solution?
Posted by: Richard Ay

Re: ISOGEN confused with +Z+X piping - 07/09/15 08:58 PM

With regards to your "C" shaped model above. If you check the dimensions on the final ISO you'll find that indeed the piping is properly dimensioned. Viewing the dimensions reveals the top and bottom horizontals are indeed parallel at a 45 degree skew.

Isogen does not produce isos to scale. The top horizontal leg appears at that offset so that Isogen can fit the dimension lines without overlapping other pipe or information - that's just the way Isogen works with pipe skewed to the major axis.

I suspect the same issue with your image above, but I can't read the dimensions to verify.
Posted by: Michael_Fletcher

Re: ISOGEN confused with +Z+X piping - 07/13/15 09:01 AM

Happy to admit when I'm wrong.

Dimensions for the x and z for all cases are the same - and after a second review, I agree - even though the main branches look odd, they are dimensionally accurate.

The only hiccup then would be the small branches, but those are unimportant for our purposes.

Consequently, it seems the only way to "fix" this currently is to be prepared for this condition, or split the model into two different CAESAR files. Unfortunately, the manual split within ISOGEN does not currently appear robust enough to handle this, as it seems to crash. Sometimes it works, sometimes not - perhaps it has something to do with multiple pipe circuits within the system. (Using the term "circuit" to distinguish it from the term "loop," so as not to confuse with expansion loops.)

If/when it comes up, I'll speak up.

Thanks.
Posted by: Richard Ay

Re: ISOGEN confused with +Z+X piping - 07/13/15 04:34 PM

Any suggestions for improvement are appreciated. If you have a particular model that is causing issues with your workflow (and it isn't proprietary), open a Support Request and send it in so we can look at it.