Interesting Kirk, Thanks for the ideas. Considering that new "industrial" Nema 12 type encoders can easily hit $500-600 each this is something to think about.
Dave On 3/5/2010 2:08 PM, Kirk Wallace wrote: > On Fri, 2010-03-05 at 10:23 -0500, Dave wrote: > >> Like you guys, I'm interested in using some of these inexpensive >> encoders. Compared to industrial units, they are a fraction of the price. >> >> The casing and wiring is obviously not "industrial" Nema 12 etc, in >> nature - no oilproof military connector on the side of the encoder and >> no bearings... >> >> So how do you guys get around these issues? Fashion some type of >> cover over the back of the motors and run the cable through a grommet? >> > Maybe this? > http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=APC1069-ND > > >> How could you use one of these encoders for a spindle encoder? Make up >> a two bearing support system with a stub shaft that the encoder can hang >> off of? >> >> I haven't heard much about US Digital's cheap encoders. What about >> Renco encoders? Is the consensus that those are ok? >> >> Dave >> > I think the cheap way to use U. S. Digital encoders is to make your own > from their hubs and sensors, which I did for my lathe: > http://www.wallacecompany.com/cnc_lathe/HNC/00011-1a.jpg > http://www.wallacecompany.com/cnc_lathe/HNC/00001-1a.jpg > http://www.wallacecompany.com/cnc_lathe/HNC/00004-1a.jpg > > For the axes encoders I made round Delrin covers with an o-ring seal. > Then used pressed in brass inserts through the cover for screw > terminals. I should install shaft seals, but I haven't gotten round2it. > > My plan for the AEAT's may be similar. The sensor boards have two tiny > plastic pins that are staked to fasten the board. A hot soldering iron > tip could soften the staking, and the board pushed out. > http://www.wallacecompany.com/machine_shop/EMC2/absolute_encoder/dcp_6877-1a.jpg > > A shaft, bearings and housing would need to be designed with magnetic > fields in mind. Using a screw terminal block on an o-ring sealed circuit > board might be a way to go. > http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=A98336-ND > > or add a few more terminals and place a differential driver chip on the > inside of the board. > > An SSI hal component is in the works too, unless someone has one > already? > ------------------------------------------------------------------------------ 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