# Drape coplanar **URL:** \ **Category:** Pro\ **Tags:** sketchup\ **Created:** [September 14, 2021, 8:23am UTC](https://forums.sketchup.com/t/drape-coplanar/175353 "2021-09-14T08:23:41Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![Grey](https://sea2.discourse-cdn.com/sketchup/user_avatar/forums.sketchup.com/grey/32/92262_2.png) [@Grey](https://forums.sketchup.com/u/Grey)\ **Post date:** [September 14, 2021, 8:23am UTC](https://forums.sketchup.com/t/drape-coplanar/175353/1 "2021-09-14T08:23:41Z")
Hi Can anybody explain why Drape does not create a coplanar line when a non coplanar line is draped on to a flat plane? Surely this is the one thing that it must get right? This software drives me nuts! Thanks ---
**Author:** ![Wo3Dan](https://sea2.discourse-cdn.com/sketchup/user_avatar/forums.sketchup.com/wo3dan/32/7450_2.png) [@Wo3Dan](https://forums.sketchup.com/u/Wo3Dan)\ **Post date:** [September 14, 2021, 9:32am UTC](https://forums.sketchup.com/t/drape-coplanar/175353/2 "2021-09-14T09:32:55Z")
> [@Grey](#): > > explain why Drape does not create a coplanar line when a non coplanar line is draped on to a flat plane? One reason might be that there is (are) hidden line(s) in the so called flat plane. Turn on visibility of hidden geometry. ---
**Author:** ![Grey](https://sea2.discourse-cdn.com/sketchup/user_avatar/forums.sketchup.com/grey/32/92262_2.png) [@Grey](https://forums.sketchup.com/u/Grey)\ **Post date:** [September 14, 2021, 9:35am UTC](https://forums.sketchup.com/t/drape-coplanar/175353/3 "2021-09-14T09:35:29Z")
Hi Thanks for getting back to me. It is a rectangle drawn in the Z-plane using the rectangle tool so no hidden lines. ---
**Author:** ![Box](https://sea2.discourse-cdn.com/sketchup/user_avatar/forums.sketchup.com/box/32/235164_2.png) [@Box](https://forums.sketchup.com/u/Box)\ **Post date:** [September 14, 2021, 9:46am UTC](https://forums.sketchup.com/t/drape-coplanar/175353/4 "2021-09-14T09:46:06Z")
Sketchup does have an annoying habit of not breaking a face when it should. It has been this way from time immemorial and will probably out live all users. There are various ways of helping it along. Selecting the parts you want and using intersect faces with… Using a variety of weld extensions that can make the break work Drawing over a segment Drawing an edge to the side Holding your tongue the right way one of which are guaranteed to work every time. There is a specific one that is well known that has been named the Bowtie bug, which is basically when a face within another face connects at only one point, easily reproduced by drawing a triangle that touches one point to the edge of a rectangle. Having said all that, sometimes your model is just wrong, as @Wo3Dan mentioned, hidden geometry can be a problem, often saved within a template. Another is length snapping being turned on which can cause tiny error, or imported cad files having their own issues. ---
**Author:** ![Grey](https://sea2.discourse-cdn.com/sketchup/user_avatar/forums.sketchup.com/grey/32/92262_2.png) [@Grey](https://forums.sketchup.com/u/Grey)\ **Post date:** [September 14, 2021, 9:51am UTC](https://forums.sketchup.com/t/drape-coplanar/175353/5 "2021-09-14T09:51:22Z")
Thanks Box. I have tried drawing over the segment - didn’t work. Never tried drawing an edge to the side so I will give it a try. It is really poor that the worst tools in Sketchup are those that are developed by Trimble. Isn’t it about time that they sorted this stuff out? I have found an extension called SuperDrape but it has a habit of crashing. ---
**Author:** ![Box](https://sea2.discourse-cdn.com/sketchup/user_avatar/forums.sketchup.com/box/32/235164_2.png) [@Box](https://forums.sketchup.com/u/Box)\ **Post date:** [September 14, 2021, 9:53am UTC](https://forums.sketchup.com/t/drape-coplanar/175353/6 "2021-09-14T09:53:04Z")
> [@Grey](#): > > worst tools in Sketchup are those that are developed by Trimble. Not so. This one has been an issue from day one. I also don’t agree with the comment in general.