[rp-ml] Drag knife and STL question

From: Liam MacGinley <rapiditup_at_yahoo.com>
Date: Tue May 23 2006 - 18:40:56 EEST

Hi there
  i hope that someone on the list can help me out with these two questions.
  1) I have noticed that the Graphtec XD700, the 3D System's Invision LD and the Kira Katana 3D printers all seem to use a "drag" knife. How can these machines cut sharp corners if they have no theta motor to orientate the knife? will it not simply round off the corners?
  2) After reading "An effective Error-Tolerance Slicing Algorithm for STL files", by L.C. Zhang, M. Han & S. H. Huang from the international journal of advanced manufacturing technology 2002, 20:363-367, i have a question about the "crack tracking method". Specifically, how do you generate a crack contour array which is an array of the unmatched edges around the perimeter of the crack. Being able to identify all the unmatched edges is relatively easy, but how do you determine which unmatched edges make up a particular crack.
   
  thanks in advance for any help given
  regards
  Liam MacGinley
  The University of Dublin
  Ireland
   
   

                
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Received on Tue May 23 18:18:24 2006

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