Re: DRO issue "HEDs in hand"

Hello,

I am using linear strips/encoders from www.encodertech.com. The
encoder and strips are about the same price as the US Digital stuff
and comes in a 0.01mm resolution which is about 0.0004". The module
is a LM-25CPMM-3T and you can get 600mm length strips. The scales are
$49.00 and modules $39.00 (almost a year ago). You can order right
from them and they are in Fallbrook CA. I have no connection to them
other than I used their product on my lathe.

I am in Canada and am used to working in mm so the .01mm accuracy
worked out well for me.

TTYL, Jeff

--- In CAD_CAM_EDM_DRO@y..., Ken Jenkins <kjenkins@b...> wrote:
> I posted a message a few days ago regarding the U.S. Digial Linear
> strip options ... 360 is the highest and in my opinion not
> high enough (360 x 4 = 1440 then 1 / 1440 = .00069 per increment.
> I want something closer to .0005 which would need 500 lpi. U.S.
> Digital in a recent email response did not sound very hopeful
> re: a linear strip with 500 lpi res. So that leaves a rotary
> encoder and wire arrangement. One would think you would want the
> highest res possible ... 2048?
>
> I have done several postings here in the past and recently ...
> other than Bubba (who has been very helpful) no one seems to
> have much information regarding what encoder works well with
> the Camtronics board. Has anyone used the 360 US Digital strips
> with the Camtronics board and got it to work and been satisfied
> with the result? OR Has anyone used a rotary encoder with wire
> loop arrangement with the Camtronics board and got it to work
> and been satisfied with the results? Could you share your experience
> here.
>
> Also, you should be aware that just having a couple HEDS does not
> help you unless they are matched to the particular encoder
> you select. The HEDS unit and the encoders are selected together
> and will not work if used with out matching them. There are linear
> HEDS and rotary HEDS and within those two groups there are specific
> ones for each resolution.
>
> Ken
>
>
> > Message: 4
> > Date: Tue, 29 Oct 2002 01:26:52 -0000
> > From: "Roger Linscheid" <r.linscheid@a...>
> > Subject: DRO encoders- Rotary or Linear?
> >
> > Hi, I am ready to begin adding a DRO to my G4003 lathe. What is the
> > current thought on the best method to accomplish my goal?
> >
> > IIRC, when I was looking into this before, the linear strips from
> > U.S. Digital were only available in 250 CPI and this was not
> > considered high enough to provide the necessary resolution. Using
> > rotary encoders meant the possibility of losing counts if the drive
> > cable slipped or stretched.
> >
> > Now U.S. Digital has linear strips in 300 and 360 CPI. Will these
> > provide a resolution of 0.0005 or better?
> >
> > I have a completed DRO board from Camtronics and several HEDS on
> > hand, so I just need to scrounge an old PC and start the installation.
> >
> > Thanks for any input!