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Trim not always working

Posted: Wed Mar 25, 2009 3:24 pm
by barjac
Could someone please tell me if this is a bug, or why trim fails in this simple example?
EDIT
http://i115.photobucket.com/albums/n287 ... cadbox.jpg
Draw the outer box using the box tool and then draw parallel lines inside each side.
Try to trim the inner large square with either trim or trim both. This seems to happen regularly in larger more complex drawings and it's becoming a real problem.
Version: 2.2.2.0 [Professional] Date: Aug 28 2008 in Mandriva 2009.0 Linux
Thanks,
Barry

Or save the text in this link as box.dxf
http://pastebin.com/f528e28bb

Posted: Fri Apr 03, 2009 6:43 pm
by J-J
Hello,
Both tools worked ok when I tried your example...(Win XP, QCad 2.2.2.0)

Posted: Fri Apr 03, 2009 7:03 pm
by barjac
Hi J-J
Thanks for your reply.
Maybe this is something specific to the Linux version. I will install it in a different Linux installation just to check it's not something to do with this one.
Cherrs,
Barry

EDIT I just tried this in the latest Mandriva Cooker and it's the same - anyone able to confirm this is a bug?

Posted: Thu Apr 23, 2009 11:50 am
by andrew
The problem appears to be the very small scale of your drawing. Try changing your drawing unit from meters to e.g. mm and scale the drawing appropriately.

I also saw that many of the lines are duplicated on top of each other. Select all and check the number of selected entities in the status bar. Should be 8 only. Delete double entities.

Posted: Thu Apr 23, 2009 2:08 pm
by barjac
Thanks for your reply Andrew
I understood that the concept of "scale" was only relevant to printing, so I am slightly confused.
Anyhow - leaving that aside - I have been working on a 12m long building drawing - hence the 1 meter units which are most appropriate. So is it unreasonable to want to draw let's say the cross section of 30 x 30 x 3mm angle iron in the detail of my drawing?
Using a similar method to my box sample trim fails in this. i.e. draw two .030m joined lines at 90 degrees for the outside of the angle and then draw two parallel lines spaced .003m on the inside of the angle. Then try to trim the inside corner.
I have tested at larger sizes and it does work, but what is the size limit and why?
This does seem to be a bug.

Yes there were multiple entities in my sample - not sure how that happened.

Posted: Wed Aug 19, 2009 7:15 am
by Gooserider
Have you tried zooming way in on the picture? I have sometimes had trouble getting trim to work well, and found that it helped to zoom in until there was little more visible on the screen than the intersection I was trying to trim... Maybe it's my aged eyeballs, :( but I seem to have trouble selecting the line clearly if I don't get in close enough on the details.

Gooserider