Expert: Bill DeShawn - 11/12/2007

Question
Sir:
I do mostly mechanical drawings in Autocad LT2006.  A reoccuring issue is how to represent (shade or hatch), straight or circular grooves which have been cut with a round (ball) nosed cutter.  If I were hand drawing the groves, I would place a series of arcs in the grooves.

There are no standard hatch patterns in Autocad LT to do this.  And a a LSP program cannot be used in Autocad LT.

Do you have a suggestion?

Thanks

Answer
Full AutoCAD has an EXPRESS TOOL that is called SUPERHATCH.  When it finishes, basically it's just MINSERT.  First off, this won't work if you don't have XCLIP.  So, check to see if you have that command.  If you do, you can MINSERT a block, and then clip it with XCLIP.  If you need a circular clip, you can do it this way:
Create a closed polyline with the polygon command using 100 sides.  I prefer the inscribed option when asked.  That will be your clipping boundary for the XCLIP command.  Make sure it's in the right place in relationship to the MINSERTed block, encompassing all the rows and columns you want to see in your drawing.  Then using XCLIP, select NEW, Select Polyline (the "circular" one).  Now you should have a clipped version of your MINSERT.  You will then see how you can draw your block to accomodate your multiple insertions so that it looks like the ball end you're looking for.  That will simulate a hatch in a circular area the same way that SUPERHATCH does in EXPRESS TOOLS.  No LSP required.

BTW, if you want LISP in LT, I always recommend DRCAUTO for LT users.  It's a very handy tool.

Apart from all of that, if shading is the way you want to go, why wouldn't you be able to use a solid hatch that you can screen at 30 percent or so?

If you don't have access to a computer when you read my response, then print it and take it with you.  Also, follow up with more questions.  Tell what you've tried and how far you got.  There's no harm in keeping the dialogue going.

DRCAuto can be found at http://www.drcauto.com


Keep in touch
Bill DeShawn
http://my.sterling.net/~bdeshawn