# PM 833T DRO install.



## 7milesup (Jan 22, 2019)

When I purchased this mill my intention was a conversion to CNC.  However, I just don't see that happening soon, so in the interim I have decided to install a DRO.  It is the typical Chinese DRO which I purchased from Siton Technologies on AliExpress.  They sent the 3 scales but the head they sent was only a 2 axis.  Looks like they are going to send me the correct one this week.  More info in This Thread.

I got some of my ideas from Rimspoke on this forum and plan on mounting the scales in the same positions that he did.  Anyhow, just a thread on how I did this in case anyone else has an 833T and is looking for ideas.  I am not a great machinist, nor really anything, but I hope someone finds this informative.

I have a lot of aluminum sitting around, including K100-S tooling plate.  First order of business was to made a "wedge" standoff for the Y-axis scale to mount to on the mill base and make it perpendicular to everything else on the mill.  For those interesed, the sides of the mill base have a 4 degree slope to them.  The scale was attached with a 1/4-28 bolt, but it will be changed to a hex head bolt as soon as I order some.






Next order of business was to determine length and configuration of aluminum bracket that will attach to scale reader.  The first "L" was added, keeping it about 1/8" off of the mill base.  Hopefully that will still be enough room for the chip shield, although, with the reader and scale upside down, I'm not too worried about contamination.














It actually stayed square after TIG'ing it.  





Next order of business was to add the next vertical piece that drops down to the head reader.  Had some tooling plate that I cut, which of course was .020" too short, so a couple shims helped me out.  















I added a .25" thick spacer at the bottom of the bracket to attach the reader to.  Apparently I forgot to take a picture after I welded it on but here it is after a quick sand blast treatment.  I don't really like how that turned out so I might re-do that, cosmetic reasons only.

Ready to get mounted to the mill....






Mounted up on the "Y" axis.  
	

		
			
		

		
	













More to follow in the coming days.....  ( I hope)


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## tweinke (Jan 23, 2019)

Nice work. It's always nice to see how different people do things like this.


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## 7milesup (Jan 25, 2019)

A little more progress today.
Added the cover for the Y axis scale.









Also positioned and drill the holes for the X-axis.  It seems like most people mount the X-axis scale on the front but on this mill there is certainly room on the back side of the table for it.  The X-axis carriage bumps up against the end of the dovetails a couple of inches before it gets to the vertical column, resulting in room for the scale.

Right end of scale bolt hole.  I am using 1/4-28 for the scale mountings.




Holes drilled 60mm apart for the read head mounting. 




Sorry about the poor picture.  Scale mounted and cover on.















For the keen eyed ones on here (aren't you all!), you will notice that of the 4 holes I drilled for mounting the scale cover, only 3 have bolts in them.  Without giving it much thought, I chose 6-32 bolts for mounting of the covers.  Only after breaking the tap off in the mill table did I remember that 6-32 taps are like the worst possible taps for breaking.  Couldn't get the dang thing out so for now it is only going to have 3 bolts in it, unless it starts to rattle, then I will have to do something different.  GRRRRRR.

Tomorrow I will post some pictures of the quill DRO that I installed along with the Z-axis DRO, which should be done tomorrow too.


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## Greebles (Jan 26, 2019)

Nicely done!


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## 7milesup (Jan 26, 2019)

Continuation of the DRO install.  Next up is the Z-axis and quite frankly it was very easy. 
Used a piece of 3/4" thick tooling plate 1" high and 3.25" long.  A .125" aluminum plate was welded to that and holes bored in it for close tolerance .250 bolts.  Corresponding holes drilled and tapped in the mill head casting for 1/4-28 bolts.











A piece of .0625 aluminum was added to the other end as a spacer for the read head.  Holes bored in the aluminum plate at 60mm apart and appropriate 5mm fasteners installed.  Z-axis done.   I am not going to install the scale cover because I don't use flood cooling and I have the opening of the scale facing away from the work, so I highly doubt that anything will get into it.


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## 7milesup (Jan 26, 2019)

I also added a DRO to the quill.  It too was a very simple install utilizing one piece of aluminum.  I did have to cut about 1.25" off of the scale of the DRO to get it to fit how I wanted, but that super quick too.
















I don't like how the readout is just magnetically stuck to the front of the mill and how the wires are not as neat as I would like.   I may 3D print a holder for the readout and better organize the wires.  I need a little time to scratch my head on this one.


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## 7milesup (Jan 26, 2019)

Speaking of 3D printing, I 3D printed a switch holder that was then placed on the side of the mill with 3M VHB tape.  The 3D printed box holds the switch and the driver for the LEDs which I have mounted on the quill.  They were purchased from Super Bright LEDs and I believe they were headlight rings for a BMW.  80mm if I remember correctly.


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## Praeger (Jan 26, 2019)

I'm just now setting up my 833T.  Thanks for posting your DRO installation, it's a help to see how other 833T owners fit the DRO scales and readers. For your quill DRO, are you still able to use the quill depth stop?  It looks like you've removed it.


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## 7milesup (Jan 26, 2019)

Praeger said:


> I'm just now setting up my 833T.  Thanks for posting your DRO installation, it's a help to see how other 833T owners fit the DRO scales and readers. For your quill DRO, are you still able to use the quill depth stop?  It looks like you've removed it.



I did take the depth stop off, but I am thinking that I can add it back on if need be.  I will have to check that out tomorrow to verify.   I really didn't see the depth stop as being that accurate, and therefore, I am not sure of the value of keeping the depth stop on.


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## TX COWDOC (Dec 13, 2020)

7milesup said:


> Speaking of 3D printing, I 3D printed a switch holder that was then placed on the side of the mill with 3M VHB tape.  The 3D printed box holds the switch and the driver for the LEDs which I have mounted on the quill.  They were purchased from Super Bright LEDs and I believe they were headlight rings for a BMW.  80mm if I remember correctly.
> 
> View attachment 285857
> 
> ...


Just set up my 833T.  The light ring is appealing to me.  How did you mount that ring?


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## 7milesup (Dec 13, 2020)

Hey Tx Cowdoc.
I used E6000 to glue the light ring up to the bottom of the spindle.  I also utilized a diffuser that can be added to the light ring.  And correction to the above statement, I think that it was actually a 90mm light ring.


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## 7milesup (Dec 13, 2020)

Also, check out this thread...there are some excellent ideas including hman's LED festoon idea.
Ideas for lighting solutions.


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## Steelbarz (May 23, 2021)

I realize this thread has been quiet for almost a year however, this is the kind of info I definitely need and am thankful for your effort in posting.  My 833 is expected in Aug 2021 so I have time to shop for upgrades.  I will be installing a DRO and I am wondering if you could provide the lengths of the scales needed.  Also, does the X Scale reduce some of the Y travel?


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## 7milesup (May 23, 2021)

Hey there.  I ordered the X-axis at 580mm.  Y-axis at 270mm, which I also specified as "slim".  The Z-axis is 440,mm.  I believe that those were travel lengths, not overall lengths.
I do not notice any reduction in Y travel.  I purchased my DRO from AliExpress.  *Here is the one I ordered and the store I bought it from.*
If I was going to do it over again I would *purchase this one instead* only because the readout would be easier to see. That one was not available when I ordered mine. Hope this helps.


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