Replace Z Value - AutoCAD LT 2014

[stiebert]

I have a drawing from a land surveyor who shot points for some anchor bolts (1000+ points) on a bridge that's approximately 2,500 LF and has a gradual arch. The drawing was done in some Civil program and is completely 3-D. I need to create 2-D railing fabrication drawings based on these existing locations. When I draw the railing in AutoCAD LT 2014, each time I reference an anchor bolt it places the new object at the Z-elevation of the anchor bolt. Thus resulting in a railing drawing that are non-coplaner (this causes problems when using fillet, trim, extend, etc).

 

I need to be either A) flatten the entire drawing (reset all Z-elevations to zero) or use a function similar to "OSNAPZ" or "Replace Z Value" selection under Drafting tab of options. BUT... neither of these choices are available for AutoCAD LT users. I could care less about the 3-D, I just want to draw a flat drawing!

 

Thank you in advance!

[tzframpton]

View this thread and refer to Post #5:

http://www.cadtutor.net/forum/showthread.php?43336-How-to-make-Z-0&

 

HTH

[Organic]

There are plenty of ways to flatten them as above. If those don't work for you then do a search on this forum and there are other methods described.

 

I'd be careful of flattening the points however. If you are drawing a railing between the coordinates (x,y,z) 0,0,0 and 10,10,20, then the rail will have a true length of 22.36m. However if you flatten the points so that their coordinates are now 0,0,0 and 10,10,0 and draw a line between them (representing the rail) then it will only have a length of 10m. If the rail resides under the deck and is planar then it isn't a problem although if it is a hand rail etc that follows the curvature of the bridge then you would have a problem if you were relying on the AutoCad lengths (and not hand calcs or third party software calcs).

 

Obviously my example was exaggerated a fair bit although in a bridge the tolerances are tight and you don't want to fabricate each railing 50mm too short etc.

[SLW210]

Since LT doesn't have the Express tool FLATTEN, nor many other 3D commands you will need to use a Macro in a button or you could draw using point filters.

 

 

"To draw a PLINE at elevation 0: If you need a polyline at Z=0, I would suggest using the Point Filter .xy. When prompted for a point, type .xy then press Enter; apply the osnap that you want and pick the point. AutoCAD will respond with (need Z): type 0 and press Enter."

 

Flatten Selection

^C^C_UCS;;_select \_move _p;;0,0,1e99;;_move _p;;0,0,-1e99;;

 

Flatten All

^C^C_UCS;;_move _all;;0,0,1e99;;_move _all;;0,0,-1e99;;