We also draw our rebar as single polylines and use colors for thickness (and plot with .ctb files). Alternatively, if you give the polylines width equal to the actual diameter of the rebar they will always be to exact scale regardless of color. Circles used for rebar in section will need to be converted to donuts with appropriate diameter and width. Such presentations will plot 1x width larger than the diameter which is also 1/2x width larger than the radius.
We have a lisp program that draws polylines and circles w/o width in slab and wall sections. The edges selected to create rebar for must be heavy polylines, not LWPOLYLINES. CONVERTPOLY can make them heavy if necessary.
The program REBAR.LSP can be found here along with any supporting subroutines: ParaCADD.com (free lisp links on left sidebar)
;;;REBAR - Draws rebar at specified spacing in already drawn slabs and walls
;;;
;;;RCORNER - Draws rebar at intersecting corners
;;;
;;;RHOOK - Draws individual rebar hooks
;;;
;;;REBARPL - Draws circles (rebar in section) along the selected side of a polyline
;;; and sets the layer of the selected polyline to match the circles created.
;;;
;;;****************************************************************************
Commands/functions defined: c:rcorner, c:rebar, c:rebarpl, c:rhook, make_rebar_group, rebar_error
Requires: mklayr.lsp, uangle.lsp, ukword.lsp, upoint.lsp, ureal.lsp
MKLAYR.LSP Requires additional subroutines which are listed under it on this page: http://paracadd.com/lisp/lisp_lst.htm
Put the lisp files in a folder included on your Support File Search Path and make it a trusted location to avoid security questions when they load.

AutoCAD User since 1989. Civil Engineering Professional since 1983
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