Lines not behaving on dwg import, QCAD version 3.19 for Mac

[David Valinsky]

Hi,

first time posting on this forum and I hope someone can help!

I am an architect and I have been sent a dwg file created in AutoCAD by a surveyor. They have explained to me that the plan has been created on a 2D plane in AutoCAD, but the elevations and sections have been drafted using 3D planes in AutoCAD before being turned into 2D blocks.

The drawing imported fine and I can use the plans as normal. The drawings created in 3D planes do not, however, behave as I would expect. This is true even after the Surveyor supplied them to me as exploded line drawings (not blocks) and double checked that z=0 for all elements, i.e. they are definitely 2D.

The problems I am having seem to arise from lines not meeting, even though it looks like they are, e.g. I cannot trim one line to another, I cannot create hatches from segments of lines in the usual way because the loop is not closed. Importantly, this is true even if I do all I can to ensure the lines meet e.g. drag one across another, use the extend tool to extend one line to another. They just don't interact with each other.

Lastly, and most weirdly, if I draw over the top of the lines in QCAD, my lines behave in the same way!

Can anyone suggest a fix for this? Otherwise my only option is to survey the surveyor's drawings and redraw from scratch.
many thanks in advance,
David

[CVH]

hi,
Did you tried Misc | Modify | Flatten on any of those original files.
It should be an early action. Once the drawing is altered with some 3D in it there is almost no way back.

Regards,
CVH

[David Valinsky]

Hi, many thanks for this suggestion, didn't know about it and it seems to have soled a lot of the issues!
That'll make my Sunday much easier,
thanks again,
David