ACAD 2000 - Polyline Width

[bsardeson]

I would like to use polyline width to represent the sawblade kerf on plywood layouts.

Kerf of sawblade is 1/8", therefore the polyline widths are 1/8" ... that's the easy part. Once the polylines are drawn on the plywood sheets, I need to dimension the all the lines.

So how does one dimension a wide polyline???

The attached example drawing has on the left a layout with dimensions snapped to the center of vertical and horizontal 1/8" wide polylines. What I would like is to be able to create a drawing as shown on the right with using 1/8" wide polys VS offseting 0" width polys.

Ultimately I am creating the objects and dimensions in VBA so by using the Polys and controlling the width i can make my code much smaller and the For ... Next loops easier to manipulate.

[rkmcswain]

So how does one dimension a wide polyline???

You'll have to eyeball your picks since a polyline only has a centerline and not edges...

Consider using a TRACE entity which resembles a wide filled polyline, except that you can snap to the edges..

[cadtag]

if all your cuts will be straight, e.g. no arcs or curves, then an MLine entity would also work. Define an mline style with a 1/16" offset left and right, and then dimension to the mline

[bsardeson]

Consider using a TRACE entity which resembles a wide filled polyline, except that you can snap to the edges..

Unfortunately, TRACE objects cannot be TRIMmed, STRETCHed, or EXPLODEd in the User Interface or with VBA (at least as far as I can tell).

So it would work great if I were always cutting squares, but alas not. Thanks for the idea though.

[bsardeson]

MLine entity would also work. Define an mline style with a 1/16" offset left and right, and then dimension to the mline

This suggestion has great merit as the MLine can be EXPLODEd to lines and arcs then TRIMmed or STRETCHed ... as a human only ... again, I cannot determine a method in VBA to perform the explosion. Ughhhh.

Well, CADTAG, you get an A for effort and now I will appeal your solution to the VBA Customization gurus to complete my mission. Thanks for the suggestion.

If a VBA solution to this is created, I will post common links to the other forum areas later.

[cadtag]

This suggestion has great merit as the MLine can be EXPLODEd to lines and arcs then TRIMmed or STRETCHed ... as a human only ... again, I cannot determine a method in VBA to perform the explosion. Ughhhh.

Well, CADTAG, you get an A for effort and now I will appeal your solution to the VBA Customization gurus to complete my mission. Thanks for the suggestion.

If a VBA solution to this is created, I will post common links to the other forum areas later.

if you need Arcs for your cuts, then I don't think MLine would work. May need to draw the center of the cut as a pline, and offset that half the kerf distance for both sides. Put the center pline on a non-plot layer, and group the three together for joint selectability. Trim, stretch and extend though won't respect the group.

[bsardeson]

if you need Arcs for your cuts, then I don't think MLine would work. May need to draw the center of the cut as a pline, and offset that half the kerf distance for both sides. Put the center pline on a non-plot layer, and group the three together for joint selectability. Trim, stretch and extend though won't respect the group.

The Mline will work since my cuts are straight and made with a saw ... for those cutting kerfs with a high-speed bit, laser, plasma, etc ... MLine will work also since the end cap for an mline can be an arc or line. The end cap will show the end relief for the diameter of the bit. IF the tool path is non-linear, just explode and fillet any bends in the path.

All fine and dandy in the manual drafting world ... still need to get a VBA solution to automate my on-the-fly design . Until a VBA solution exists to manipulate the MLine and it's properties & styles I'm forced to offset standard or poly lines, trims and extends, Essentially tripling the amount of VBA code necessary to complete the job. Ugh.

I suppose though, I could just continue to use the MLine and NOT trim the ends to the finished shape leaving them overhang for layout reference lines. Hmmmm, wonder if manufacturing layout peeps will care about the aesthetics.

[ccowgill]

Although your post says AutoCAD 2000, I dont know that a vba solution is the way to go, in the future, if your AutoCad is upgraded, VBA may not be supported. I believe as it is now, in 2010 and 2011 you have to download an add-on that allows VBA to function.