On Sat, 2010-02-27 at 22:21 -0500, BRIAN GLACKIN wrote: > I may pick up a set of linear scales which were part of a DRO for a milling > machine. > > The DRO box was fried but the scales are reportedly still working. If I get > these scales, will I be able to hook them up using one of the available > boards (mesa or pico)? I have a 13.5X40 lathe I am considering using these > for. > > Any suggestions including what to look for with used scales are appreciated. > > Brian
If the scales have quadrature output, then you should be able use a parallel port, Mesa or Pico. http://zone.ni.com/devzone/cda/tut/p/id/4763 http://en.wikipedia.org/wiki/Rotary_encoder Some scales don't use quadrature, so at best, you would need a converter. Using a linear scale for the primary encoder is not recommended. Usually there is a lot of feedback latency between the axis motor and the encoder, which causes feedback loop instability. Some here have used linear scales in combination with motor shaft encoders, but this is not for novice integrators. Compared to a proper motor or ball screw rotary encoder, the most common linear scales don't have very high resolution and rotary encoders can be cheaper. Although this comment may be out of date, because a lot of the newer scales have had pretty high resolutions, but still not like a rotary. You may want to consider fixing the DRO display or selling the scales separately and use the money to get rotary encoders (,or beer). -- Kirk Wallace http://www.wallacecompany.com/machine_shop/ http://www.wallacecompany.com/E45/index.html California, USA ------------------------------------------------------------------------------ Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
