New Ultra Small DRO just installed

Very clever indeed, Jim.

I'd be reluctant to do that much "surgery" on my saddle however.

The magnetic tape sure gets the ideas flowing though.
 
I talked to DroPros today and got a lot of info.

Even though they've been selling the Magna Slim scale systems for a year they still do not have anything on their website, citing lack of time, and lack of updated mounting hardware from Electronica. Apparently customers are complaining about the mounting hardware.

He agreed that the typical X-axis installation of their standard magnetic scales blocks the gib lock screw, but he directed me to a pic (below) on their website showing a comparison of mounting the scale "edge-wise" (vs "flat wise") which would clear the gib lock screw on the cross-slide. He also concurred that this and other mounting methods will reduce the "reach" of the tail stock, but that a bumper can prevent crashes.

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He also commented that while the Magna slim Scales that are normally "bundled" with the D80 counter/head, they will work with the EL400 counter/head, although they wouldn't break up a D80 system. Meaning I would have to buy the EL400 counter/head seperately.

The EL400 system with standard magnetic scales for my 12x36 lathe is $965 (presumably plus shipping).

The D80 system with Magna Slim scales is $629.

I'm not crazy about the idea of having a different counter/head on my mill than on my lathe. So I'm gonna "reconnoiter the sitiation" longer.
 
My lock is a flat set screw in the hole just to the left of the read head and below the scale. As you can see I could have raised the scale a bit for more clearance but there is enough room for a hex key like this. The lock can be covered by the read head if the cross slide is moved to the center, but (for me anyway) that is an improbable position. The read head could be mounted more to the right if needed.
The 2 socket head mounting head bolts act as a bumper for the tail stock. Hitting the bolts with the tail stock is no more of a problem than is running a tool into the chuck.

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After much consideration I've decided to forego the miniature magnetic scales and read head in favor of the "standard" magnetic scales and the EL400 head from DroPros.

I can keep my gib lock screw accessible by using "pads" to stand my x-axis scale away from the mounting surface like Frostheave did in the link below. It will reduce the available tail stock travel, but I think it's an acceptable trade off, and I can install a bumper so there will be no tail stock crashes.

I had a couple scales left over from when I transplanted the DroPro system from my original big mill/drill, to my Bridgeport, to my new Acer e-Mill, needing a longer scale for each transplant. Consequently, I ended up with some spare scales, and I could purchase a new DroPro EL400 Lathe kit with a shorter X-axis scale that what my 12x36 lathe would ordinarily call for. I can cut one of these spare scales to fit the x-axis, saving me about $120. This put me within a couple hundred dollars of the cost of the Ditron/Magna Slim kit., which is a small price differential to pay for my preferred EL400 system

The kit has been purchased and will arrive shortly. I'll take pics as I install, and post them here.

https://www.hobby-machinist.com/threads/g4003g-lathe-x-axis-dro-scale-install.24468/
 
Why not extend the scale off of the back of the carriage and cross slide. Below is a picture of my Scale setup. The cross slide is all the way back towards the operator and as you can see it does not effect the travel of the tailstock. It’s a very rigid set up and I’ve never had an issue with inaccurate readings due to flex [
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QUOTE="jmarkwolf, post: 649736, member: 20532"]
After much consideration I've decided to forego the miniature magnetic scales and read head in favor of the "standard" magnetic scales and the EL400 head from DroPros.

I can keep my gib lock screw accessible by using "pads" to stand my x-axis scale away from the mounting surface like Frostheave did in the link below. It will reduce the available tail stock travel, but I think it's an acceptable trade off, and I can install a bumper so there will be no tail stock crashes.

I had a couple scales left over from when I transplanted the DroPro system from my original big mill/drill, to my Bridgeport, to my new Acer e-Mill, needing a longer scale for each transplant. Consequently, I ended up with some spare scales, and I could purchase a new DroPro EL400 Lathe kit with a shorter X-axis scale that what my 12x36 lathe would ordinarily call for. I can cut one of these spare scales to fit the x-axis, saving me about $120. This put me within a couple hundred dollars of the cost of the Ditron/Magna Slim kit., which is a small price differential to pay for my preferred EL400 system

The kit has been purchased and will arrive shortly. I'll take pics as I install, and post them here.

https://www.hobby-machinist.com/threads/g4003g-lathe-x-axis-dro-scale-install.24468/
[/QUOTE]
 
Groundhog said:
I've just completed the installation of a DRO for my 12x36 Central Machinery lathe.

I was concerned about covering the carriage oilers and lock with a DRO. But Dan at DRO PROs suggested a new system that they just got in. It is not much more expensive than glass scales and cheaper than many other magnetic scales I've seen.

The system uses Electronica “Magna Slim Scales” (magnetic) and EMC14A reader heads (all IP67 contaminate proof) and a Ditron D80 LCD display. I believe the scales are fairly new industry wide. I got 5 micron (0.0002”) resolution on both axis.

The read head is tiny at 36mm (1.417”) x 13mm (0.511”) x 14mm (0.551”). The scales are a lot smaller than standard magnetic scales measuring 15mm (0.590”) high and 7.2mm (0.283”) thick with their protective covers. The scale can be read from end to end and does not need additional space for end caps. To be able to read, say, a max of 6” you only need room for 6” total. Not 6” plus 2, 3 or 4 inches of unusable/unreadable end caps or safety margins. The mounting screws are underneath the scale.

I would think that the small size and being able to read the entire length of the scale would make them especially attractive to users with smaller (and mini) machines and other space limited installations.

Note that in my installation I used the entire length of the scales as shipped.
Since they will not interfere with anything at this length I couldn't see any advantage in cutting them.

Explanation of the pictures is in the order that they appear;

#1: Here, the center extrusion is temporally held in the approximate position with double sided tape. On final assembly this center part “floats” between the 2 fixed end pieces (no tape or mounting screws). One end piece with mounting holes is laying to the left.

#2: The left end piece in place (the illusion of it being crooked is caused by camera angle). Once both end pieces are installed, leveled and inline with each other the center part just “floats” between them – held by the scale's stainless backing. The screw in the bottom center of the end piece (you can just about see the head) eventually tightens down on the strip to keep it from moving.

#3: A drawing of an end piece. The scale is flexible like a refrigerator magnet and molded to a thin strip of stainless steel that is just wider than the magnetic strip. The stainless strip slides into the slot of one end piece, through the slot in the center section and into the slot of the end piece on the other side.

#4: End pieces, center extrusion and magnetic strip scale in place. The protective stainless steel stick-on cover is not in place yet. Notice that I will still be able to get to my oilers and carriage lock (the hole towards the back of the picture). The oilers would have been inaccessible with standard magnetic or glass scales and the carriage lock too close for comfort.

#5: The read head and protective strip in place. The gap between the ends and center extrusions is called for in the instructions. DRO PROs don't have new hardware for this system yet so they sent the stuff from the standard sized system. The standard read head would have taken up that entire top surface of the black mounting block. I could have milled the block to fit the read head and made it much smaller (and I still may sometime) but it shouldn't cause problems as it is.

#6: Todd (DRO PROs) said just to shim the end pieces to get everything in line. I found one spot on the lathe casting that was especially high (the casting is wavy). So I decided to hit it with a flapper disc and take the high spot down a little. I discovered that the entire base casting is covered with a thin layer of automotive body putty!

#7: One of my first paying jobs (other than sweeping the floors) was at my dad's Chevy dealership's body shop (where I quickly learned that there is no such thing as body work – there is just sanding). So it just kind of evolved from that first little high spot that I flattened the whole scale path by sanding rather than shim the ends. I got the entire path within +0.01mm -0.08mm and one little shim on the left end. The only way I know how to sand is like you would a car and feather-edge it, so that is why the sanded area is so wide.

#8: The Z axis read head and stainless steel protective strip in place. Again, the read head mounting hardware is much bigger than needed. Maybe some day I will paint the sanded area (all body putty – no bare metal) and mill down the hardware. Maybe. Someday.

#9: Everything tested and in place. Just running the wiring cables. I'm told that between the IP67 water resistance rating, being almost totally enclosed by the extrusion and the front protective stainless strip that there is no need for a protective cover. When I first learned of no protective covers and of floating centers I was sure I would be making some design changes. However, now that I see it first hand I am a lot more comfortable. It is much more robust than you would think and I doubt I will need or want to make those additions.

#10: The lathe is back together and ready to run. Except for a new drive belt that I ordered locally, was told (after a supposed phone call to somewhere to confirm stock) it would be here the next day. That was last week. Friday they said it should be here next week. And, they will probably want full retail plus shipping when it finally does get here. They won't get it!

#11: The Ditron display. There are 4 icon menu bars available (bottom of the LCD) that can be rotated through with the up/down arrow keys . The F buttons access the different features (icons) of whichever menu bar is displayed above them. The pertinent section of the owners manual (in real English) is available within each menu item as help screens.

All in all is seems like a good system. I'm happy with the purchase, the price and especially with the help I've gotten and ease of dealing with DRO PROs. Of course the real proof will be when I start using it (need that belt). I'll keep this post updated.

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#7View attachment 256905 #8View attachment 256909 #9View attachment 256906
#10View attachment 256907

#11View attachment 256908
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Did you have any calibration issues??? Is there a way to offset the axis? I have 1 micron scales and I’m reading 2” shorter on all axis than the actual mechanical travel. Can’t seem to find what’s causing it.
 

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Is your dro set to the right resolution for the scale? Calibration menu is located in the soft keys at the bottom of the screen.
 
I understand (no experience, though I have installed a standard magnetic scale set to a lathe) that with the ultra small scales it can actually be possible to put all the hardware inside the cross slide on some lathes. Now, THAT would be extremely cool, out of the way and away from getting damaged...
 
Bob Korves said:
I do not like the idea of a cross slide scale on the tailstock side of the carriage. Good way to destroy it, and to not let the tailstock get as close as possible to the work. I understand that the mini scales can fit under the cross slide on some lathes, which sounds like a good idea if it does not interfere with anything.
Click to expand...
I have the iGaging scale mounted on the tailstock side of the cross slide and I was concerned about the tailstock running into the scale as well. I added a stop to prevent the tailstock from contacting the scale. I did lose some tailstock travel but both the live and dead center are past the center line of the cross slide in their retracted position.
Tailstock Stop .JPG
 
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