Straightening skewed elevation views

[dbaldacchino]

I'm looking at a project that has some skewed elevation views. Basically, when an elevation tag was placed in plan, in the vicinity there was a segmented curtain wall (approximating a curve) and the elevation tag snapped perpendicular to one of the CW faces, which was not perfectly perpendicular to what the user wanted it to be. I cannot find a way to rotate this view to be perfectly perpendicular. I can recreate the elevation but was wondering if there's a trick to fixing it without re-doing the view (there's a lot of extra linework editing etc. in the current view, which I'd rather not have to redo). Seems odd that you cannot even snap to the direction of the cut plane in plan; if this was possible then this wouldn't be an issue. Thanks in dvance.

[dbaldacchino]

Wow, I found a way worthy of a tutorial :) I'll write one up when I get a chance.

In essence, orient your view to the skewed section/elevation. Then rotate your 3D view so you can see the edge of the section box. Now draw some model lines by picking on some objects that are being cut by the section box. If you don't have any of those, just draw some temporary walls that cross that section box. When you draw model lines by picking walls, the model line will stop exactly at the section box, so all you need is two of these lines and you've got your 2 points to draw a detail/model line in plan. That line will lie exactly on your cut plane. If the angle is too small (mine was only 0.625 degrees off), Revit won't rotate it. I had to rotate the elevation and the line by an arbitrary amount first and then straightened them again by repeating a second time.

In the process I discovered a very odd bug. If you try and draw a model line that snaps to the end of a model line that was created by picking on sectioned objects, the line won't be visible in the 3D view, but is visible in plan! If you nudge that line or move it by a set distance away from that snapped corner, it re-appears.

[dbaldacchino]

Had some time to kill, so here's a little tutorial :)

EDIT 2015-11-25: Trey's method below (click here (http://forums.augi.com/showthread.php?59475-Straightening-skewed-elevation-views&p=1304778&viewfull=1#post1304778)) is faster than the method posted here. Both achieve the same thing with utmost accuracy but using a ref. plane in the elevation view gives you a perpendicular line to the cut plane, which you can then rotate together with the elevation tag to straighten things up.

[zanzibarbob7]

David, I've had this same problem but here's the solution I used. Very simple and accomplishes the same thing, unless I'm missing something.

[dbaldacchino]

Thomas, that's the same concept I'm using. However, it's not accurate, it's an approximation, since you cannot snap to the endpoints/intersections of the elevation tag. With the method I described, you'll be able to get it perfectly aligned since you're actually snapping to the endpoints of the model lines (the ones cut by the section box). It's also a great method for when you want to create a ref. plane that lies exactly on the cut plane of a section/elevation view. Unfortunately it's very difficult to get an elevation or a section cut plane exactly where you want it (unless you use the Attach to Grid option, which puts the elevation cut plane exactly on the grid line). Even when drawing a new section, you can only snap to a gridline or ref. plane.

With this method, if the elevation has already been placed, you could sketch a model line or ref. plane exactly at the cut plane and then rotate/move both tag & line and rotate them exactly where you want them, instead of having to re-create the view and using the grid trick.

[DaveP]

Update:

In Revit 2010, the View -> Orient -> To Other View command is no longer in the menu, and the Ribbon doesn't have a replacement for it, which means you can no longer follow Dave B's process exactly. Fear not, however. There's only one slight change.

The replacement for the View -> Orient -> To Other View command is to right-click on the View Cube in a 3D View and Select Orient To View -> Elevations and the select your elevation from the list.

[dbaldacchino]

Thanks for the update Dave! One bummer with this change is that we lost the option ot Orient by Plane. I found that to be very useful in the past.

[ron.sanpedro]

Thanks for the update Dave! One bummer with this change is that we lost the option ot Orient by Plane. I found that to be very useful in the past.

Orient to a plane is still there, just stuck in the right click options of the steering wheel, while all the other "orient to" options are a right click option of the View Cube. And none of them in the Idiot Ribbon. Nothing like a little UI inconsistency to make life harder than it has to be. ;)

Gordon

[dbaldacchino]

I'll be darned! I forgot it's there haha. Thanks for the heads up. Maybe they'll straighten things out for the upcoming release ;)

[mmc]

this thread saved my bacon...thanks guys!

[dandlf]

Thanks Dave, you also saved my bacon today after going around in loops trying to work out why 1 of our elevations was exported incorrectly. Turns out it was a skewed Elev.
cheers

[dbaldacchino]

Good to hear, I still find elevations/sections slightly rotated from time to time, in which dimensions won't work. So after all these years, it still comes in handy!

[jeffh]

Good to hear, I still find elevations/sections slightly rotated from time to time, in which dimensions won't work. So after all these years, it still comes in handy!

I tihnk there is an easier way to do this. It might not have existed when this tutorial was first written 6 years ago. But now if you have an elevation marker slightly off axis you can fix it by selecting the body portion of the elevation marker and then rather than use the rotate command from the Modify tab, use the rotate grip that is shown to rotate the elevation marker. Using this rotate gizmo the "hunting" behavior (the processuses to snap an elevation parallel to a plane in the project) will be used during the rotation and the elevation will "snap" into place.

[dbaldacchino]

Thanks for the tip Jeff! Didn't realize that, although it is finicky to get it to work since I'm not seeing any tracking feedback as to what it's snapping to. Unfortunately this is only available for Elevations, so Sections still need to use this long-winded technique to be corrected.

[jeffh]

Yeah sections are a bit more tricky because they don't have the "hunting" behavior elevations do. There is more of a chance the section was intentionally drawn off axis. I am not totally sure what the hunting behavior of the elevation markers tracks but if I had to guess you could isolate the walls and the elevation marker with the sunglasses first and then use the rotate gizmo to insure you were rotating to the wall. With the visibility of other categories off they would not be "seen" by the elevation marker.

[dbaldacchino]

Jeff, it seems that the snapping/hunting behavior is not very reliable and sometimes it just plain doesn't work. I've had this happen on some occasions and other users are reporting similar experiences. Here's a post (OMG I'm going to cause a circular reference now as that post is referencing this one!):

http://www.revitcity.com/forums.php?action=viewthread&thread_id=31145

I'm not sure this is happening because there might be too many things in the view and the elevation tag just doesn't try due to performance (hardcoded behavior?) but if I recall, I temporarily isolated the wall I cared to snap to and the elevation tag but it still wouldn't snap. Might be worth a try if all else fails, and then on to the long-winded method described in this post, which is recommended only when you have a lot of time invested alread in detailing a particular elevation with tags, notes, etc.

[TreyK]

Hey Dave... this thread is a couple of years old, but I was putting together some Tips & Tricks for AU this year and I wondered if you know this method:

For sections (which don’t rotate with snaps) or for elevations if rotating the symbol didn’t work…

1 Open the section (or elevation) that’s slightly off. In Architecture tab > Workplane panel, click Ref Plane and place a vertical ref plane (let’s call it Bob) in the view.

2 Open the plan view and select Bob. Move Bob so that it touches a face of the geometry (a wall, probably) to which you want to align.

3 Select both the ref plane and the section line and click the Rotate tool in the ribbon. Click-drag the rotate centroid and drop it on the intersection of Bob and the element face. Click further up on Bob to begin the rotate, and then click further up on the element face to snap the rotate. Done.

Also, if some of the walls in the project are slightly askew and this issue keeps happening... maybe THEY should be fixed instead of the elevations/sections! Assuming the geometry should be aligned with project north: draw some vertical and horizontal ref planes, place an angular dim between the geometry and its perpendicular ref plane, select the geometry to which the dim is referencing, and directly type “90” (degrees) into the dim. The geometry (which was probably something like 90.00507 degrees) is now squared-up! Repeat this until all is square.

What do you think? Reasonable advice?

Thanks,
Trey

[DaveP]

Trey, will this work with your example of the angle being off by 0.00507 degrees?
I've always had problems rotating by a tiny amount like that. Revit wants to snap to even degrees, or at least it seems to prefer the original angle.
In the past, I've had to Rotate too far (like 10 or 20 degrees) and then rotate back to the angle that's only slightly different from the original.

And thanks </sarcasm> for reminding me of the walls being skewed. On one of our earlier projects, we that we we being smart and use the "Pick Line" tool to trace our structural grids. Only weeks later when we tried adding dimensions and couldn't (because things weren't parallel) did we learn the they were off by a few hundredths of a degree. But across a 350' building, that added up to 4 or 5 inches. So we had to first go back as you suggested and add Angular Dimensions (cranked to 8 decimal places) to find out which were off. Then crawled our way across the building & typing in 90.0 ti all those that were off. And THEN going back to fix up walls. Lots of remodeling. :shock::cry:
That was the last time we trusted a linked DWG.

[TreyK]

Hi Dave--

>> will this work with your example of the angle being off by 0.00507 degrees?

Yeah, this will work. You can verify it by (temporarily) setting your dimension type parameter accuracy out to 12 digits. You'll see the dimension reporting something like "90.00507011744". After you type in "90" it will display "90.000000000000". Yay!

Trey

[dbaldacchino]

Hey Trey, love it! It's definitely faster than my method :) I tied with an angle of 0.0057 degrees but I had to rotate Bob and the elevation tag to align them with the skewed wall, then rotated back by exactly 90 degrees. For slightly larger skewed angles, this might not be necessary (actually my original instructions on this part still apply; using he ref. plane though is faster than having to create a 3D view and 3 model lines). Thumbs up!

Yes I do agree that if the walls are erroneously skewed, they should be fixed. However any time I came across a skewed elevation, it's mostly been because Revit inferred the wrong face to be perpendicular to, such as in my original example of a curtain wall panel.