2D file, 3D reference - cannot draw perpendicular?

That works great if your 3D element is a line, or you know exactly where your perpendicular needs to be. Not so easy if you're dealing with a 3D arc and you need to draw from "This point over here" to "Wherever the perpendicular hits".

Accudraw RE and RQ do help, but they don't cover everything.

You will not be able to draw a line perpendicular from a 3d reference file with a 2d active file, you will get a message "out of plane" in the prompt window.

What I do is use my accudraw RC (rotate quick ) to rotate my accudraw compass, so that it is in line with the element that is in the 3d reference file, with my compass lock in it easy, and then draw my line.

I do not have a solution for an "apparent perpendicular" snap, I would think one should be able to use tha ACS and plane locking to accomplish this. Although I would have also though if I am in a 2D model I would not have to worry about 3D issues [WRONG]. I hope some one has a simple solution to this one as well.

How about drawing "perpendicular" lines? Sometimes I am asked to verify my measurements and the fastest way to show them to people is to turn on a set of lines. I can't currently do that easily with XM. Certain combinations of snaps and points can give me wildly NON-perpendicular lines.

Are there any ACS-thingys to mess with in 8i?

I understand the 3D concepts about why my lines may or may not be "true" perpendiculars, but I'm in a 2D drawing working from a 2D viewpoint. I'd like the 3D element to respond like the 2D view.

I'll give 8i a look. Thanks!

V8i gives both the "true" & "projected" measurments.

Solution:

CR# 131267

Problem :

2d master file with a 3d file referenced to it. Trying to take measurements from points in the reference file (snap) and they are getting the true 3d distance rather than a straight 2d measurement horizontally.

I have a 2D drawing that has a 3D drawing attached as a reference. I am trying to get some measurements between my 2D elements and a couple of the 3D elements, and I'm having trouble.

I have some construction lines drawn in, Smartlines from my known point to the reference element using the Perpendicular snap. These lines are (apparently) NOT perpendicular to my reference element, however - I get an angle of 89.9263 degrees (in View, True and Accudraw mode) instead of 90 degrees. The length of these lines is different from a distance measured perpendicular from the same element to the same point.

WTH?

How can I measure (and verify!) 2D perpendicular distances when 3D elements are involved?
Why aren't my perpendicular lines at 90 degrees?
Is this another one of those ACS things?

Thank you.

MaryB
MSTN 08.09.04.88