Which Magnetic Scales

H

Hozzie

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After reading one of the other threads I have decided I like the idea of using the TouchDRO system. I plan to order Magnetic scales to put on my Jet JTM-4VS. It has an old Sargon DRO which works, but is only 2 axis. I decided to just go ahead and replace everything with new now, add a Z and tach and be done with it.

So looking at Magnetic scales, I am basically going by some common brands. There is Ditron at the cheaper end, but they seem to work pretty well from what I can tell and then I have looked at the Mitutoyo's which are more expensive. I am not against spending the money if it makes sense, but I am not sure if it is really needed. I am just a home hobbyist.

So what I have looked at:

Mitutoyo: https://www.mscdirect.com/product/details/05936141
What I can't seem to find is the voltage, etc these use so not sure they would even work. These appear to be ABS scales so not sure that is supported either. To get all three sizes I am looking at approx $900. Maybe there are other version of the Mitutoyo's I should be looking at if I want "better quality" scales than the Ditrons?

Ditron:
I see they show three different types (DMA, DMS, DMB). No idea what the differences are and which may be the best option. I am guessing these would be around $500. I am confident these are supported.

Are there better options? Recommendations?

While I am asking I figure Yuriy will see this. I was looking at getting the Lenovo Tab M10 Plus, 10.3" FHD Android Tablet, Octa-Core Processor, 64GB Storage, 4GB RAM tablet for the display. Is 4GB RAM good enough?

Thanks.
 
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I have Ditron DMR-200 1 micron read heads on my lathe. About $100/ read head and about $30/meter for the magnetic tape. I can't see any difference between those and Renishaw units that I have on my mill.
 
I don't have any experience with Mitutoyo magnetic scales, so I can't comment on those.
On the other hand, I know a fair number of people who use Ditron DMR-200 and DMR-500 scales and they seem to be very good. I have DMR-500 on my mill (on the X-axis), and for a long time had one on the lathe's Z axis and haven't had any problems. If you get a version with bulk tape, the edges tend to collect fine swarf, but the ones that have the tape in the aluminum extrusion with a stainless steel cover don't have this problem. Other than that, they have been very accurate and trouble-free for several years now.
One caveat I have is that these scales are very particular about the input stage, so I strongly recommend the new version of the pre-assembled TouchDRO adapter. If you absolutely insist on a scratch-built adapter, use pull-up resistors with at least 47KOhm resistance and some sort of buffer (i.e. a simple resistor divider will not work very well).

Hope this helps
Yuriy
 
Thanks, I wasn't considering anything other than the versions with the tape in the aluminum extrusions and covers so that shouldn't be an issue.
 
I'm using a Mitutoyo 2 axis KA counter with magnetic scales on my vertical mill and have to say that I have been very
happy with it. Having used it for some years now, it's operation has been flawless.:encourage:
 
cathead said:
I'm using a Mitutoyo 2 axis KA counter with magnetic scales on my vertical mill and have to say that I have been very
happy with it. Having used it for some years now, it's operation has been flawless.:encourage:
Click to expand...
Do you use them with TouchDRO, or their own display?
 
I ordered 3 Ditron 1um scales sized for my exact needs. $509 total delivered. Ditron was easy to work with and swapped out the 5um scales for the 1um for no extra cost. I also ordered the V2 adapter and case so that should be good. I got some good feedback in PM about considerations, but being in the software business, I like the idea of this concept. I am an Apple guy, but will get an Android tablet ordered. Should be fun to setup.
 
JimDawson said:
I have Ditron DMR-200 1 micron read heads on my lathe. About $100/ read head and about $30/meter for the magnetic tape. I can't see any difference between those and Renishaw units that I have on my mill.
Click to expand...
Jim,

Did you have a source for the aluminum rail and stainless tape cover? Or, did you use another mounting method?

Thanks,
Bob
 
frostheave said:
Jim,

Did you have a source for the aluminum rail and stainless tape cover? Or, did you use another mounting method?

Thanks,
Bob
Click to expand...

The one's I ordered are in the rail with the cover. If you did three axis at his cost, you are at ~ $360. Then you have to buy the rail and covers. Not sure it would be worth the effort to do vs. just buying them in the rails already at the exact lengths you need.

If it helps anyone, these are the items I ordered. You will need to message them for the specific lengths you want and then they will have you purchase based on the 5UM and they will update the order.

DMA2-950MM (The dro can read 950mm . Total length of magnetic scale =1069mm )
DMA2-350MM (The dro can read 350mm . Total length of magnetic scale =469mm )
DMA2-450MM (The dro can read 450mm . Total length of magnetic scale =569mm )

They said the DMA2 represents the 1um scales.

This is the link to the page for the actual product.
www.aliexpress.com

125.12US $ 8% OFF|High Precision Rs422 Ip67 Magnetic Scale 5um 50-500mm Reading Length Magnetic Linear Encoder Mainly Used For Woodworker - Level Measuring Instruments - AliExpress

Smarter Shopping, Better Living! Aliexpress.com
www.aliexpress.com www.aliexpress.com
 
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Hozzie said:
The one's I ordered are in the rail with the cover. If you did three axis at his cost, you are at ~ $360. Then you have to buy the rail and covers. Not sure it would be worth the effort to do vs. just buying them in the rails already at the exact lengths you need.

If it helps anyone, these are the items I ordered. You will need to message them for the specific lengths you want and then they will have you purchase based on the 5UM and they will update the order.

DMA2-950MM (The dro can read 950mm . Total length of magnetic scale =1069mm )
DMA2-350MM (The dro can read 350mm . Total length of magnetic scale =469mm )
DMA2-450MM (The dro can read 450mm . Total length of magnetic scale =569mm )

They said the DMA2 represents the 1um scales.

This is the link to the page for the actual product.
www.aliexpress.com

125.12US $ 8% OFF|High Precision Rs422 Ip67 Magnetic Scale 5um 50-500mm Reading Length Magnetic Linear Encoder Mainly Used For Woodworker - Level Measuring Instruments - AliExpress

Smarter Shopping, Better Living! Aliexpress.com
www.aliexpress.com www.aliexpress.com
Click to expand...
Very good. Thanks for the info Hozzie.
 
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