Author Topic: M-DRO  (Read 2656 times)

jpigg55

Re: M-DRO
« Reply #30 on: September 18, 2019, 04:40:07 PM »
Just a quick note today.
Finished installing the Z-axis scale with initial test run of full travel. Everything worked great, took a couple pictures of it as well.
The third picture is of the test data sheet that comes in each of the readhead packages, something I forgot to mention earlier. For this particular readhead test datasheet, it lists a Max deviation of 0.002 and a Min deviation of -0.002.
Looking at the rest of the data on the sheet, I take this to mean that the readings coming from the readhead would range anywhere for +0.002 mm higher than the test standard and -0.002 mm less than the standard at various test positions based on the printed and graphed data points.
SB 9A, Clausing 8520, Sanford MG 612

woodchucker

Re: M-DRO
« Reply #31 on: September 18, 2019, 06:21:32 PM »
you look like you covered your gitz oil port.
Jeff
Clausing 8520   SB Model 9a - power hacksaw, Milwaukee band saw in a table.  Delta Rockwell Surface Grinder
For pics: https://imgur.com/user/woodchucker/posts

Remember measure once cut twice, or was the measure twice cut once...

jpigg55

Re: M-DRO
« Reply #32 on: September 18, 2019, 08:24:34 PM »
you look like you covered your gitz oil port.
Nope, I can still get to it. I've been careful during the install to not cover any or make an access hole to get to it.
SB 9A, Clausing 8520, Sanford MG 612

jpigg55

Re: M-DRO
« Reply #33 on: September 24, 2019, 07:52:16 PM »
Almost have the Y-axis scale mounted now. One I thought would be the easiest has turned out to be one of the more difficult. I ended up drilling and tapping a couple ľ-20 holes in the cross-slide for mounting the readhead. Something I hoped I wouldnít have to do, but ended up to be my best option. I also ended up machining the mounting bracket as I couldnít make any of the included brackets work.
Now that I have the readhead brackets made up, all thatís left is to align the scale extrusion (hence the magnets in pic #1), drill and tap for the extrusion mounting screws, install and level it, clean the surface and stick on the magnetic tape, install the cover strip and protective cover, and lastly, reinstall, align and space the readhead, and tighten everything down.
Barring some unforeseen interruption, I should finish the install tomorrow.
SB 9A, Clausing 8520, Sanford MG 612

jpigg55

Re: M-DRO
« Reply #34 on: September 25, 2019, 03:15:53 PM »
I finished installing all 3 scales, so with the exception of tying up the cords, the install is complete.
For final thoughts, the installation process was a bit more involved than I anticipated, although manageable. For anyone reading this and considering M-DRO scales, ensure you have some material available for making any pieces necessary. Also have drill bits and metric taps for 3 mm & 4 mm bolts and screws. I also recommend using the scale covers since ferrous chips will be attracted to the encoder tape.
For cutting the scales to length, I used my HF metal bandsaw to cut the extrusions and covers, but a hand hacksaw will work fine. For cutting the magnetic encoder strips and stainless cover strips, I recommend either a Dremel (or Dremel like tool) or a sharp pair of sheet metal shears which is what I used, worked great.
Here are a few pictures of the Y-axis final install along with a link to a short video of my completed work.
https://drive.google.com/file/d/17mFHdIlQwyBB1QxiAscbayzcR3Hfmgts/view?usp=sharing



SB 9A, Clausing 8520, Sanford MG 612

jpigg55

Re: M-DRO
« Reply #35 on: September 25, 2019, 03:17:36 PM »
More pictures.
SB 9A, Clausing 8520, Sanford MG 612

jpigg55

Re: M-DRO
« Reply #36 on: September 25, 2019, 03:20:25 PM »
Next, Iíll be putting together a Touch DRO controller for use with these scales. Partly due to me realizing too late Iíd ordered the kit with the lathe display unit and partly due to me liking the Touch DRO App. Along with this, I plan on doing some O-scope runs and getting the CPI count from these scales during the calibration process since Iíll have access to the connections. I plan on posting all this test info in another thread once done. Iíll amend this post with the link to that thread once itís uploaded.
 Since the M-DRO display I have is for a lathe, Iím going to try using it with the set of quadrature scales I got from ďThe Little Machine ShopĒ on my lathe. Maybe Iíll do another thread on that as well if it works.
SB 9A, Clausing 8520, Sanford MG 612

jpigg55

Re: M-DRO
« Reply #37 on: November 03, 2019, 08:39:31 AM »
Sorry about the late update. I got everything connected and running, very happy with the new scales.
Initial testing didn't show anything unexpected or out of the ordinary so I probably won't bother posting a thread on it.
Scale CPI was right in the neighborhood of 5080 with them being 5 micron rated scales.

One last thought I figured I'd mention. In the future, I'm considering adding a scale to my spindle for summing with my Z-axis.
Nothing earth shattering there, but since I decided to use Touch DRO for my interface instead of the OEM display, using these scales gives me an added option.
M-DRO offers a scale summing interface for this purpose. https://www.sra-measurement.com/m-dro-linear-encoder-summing-interface
I'm uncertain if other manufacturers offer this option or not.
This can be done without the interface by Touch DRO and other displays by using the 4th axis connection and programming the display to sum the values.
By using the M-DRO unit, I will be able to sum both scales and still have the 4th axis connection available for other uses.
SB 9A, Clausing 8520, Sanford MG 612