# MagXact DRO for PM-833T



## Rhizome (Mar 21, 2021)

Hi,
Has anyone installed the MagXact DRO for a PM-833T?  I think it is a new item from PM, so there isn't much information on it on the website.  I am hoping for some end-user feed back as to the pros and cons vs. other DRO such as DROPro, etc.
Thanks!


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## BladesIIB (Mar 21, 2021)

I have the MagXact from PM on my PM 11440TL Lathe.  I don't think the install should be any different than their other models.  The difference with the MagXact is the scales are magnetic instead of glass scales.  This makes them less susceptible to getting dirty, so lower maintenance.  As far as I know that is the key difference.  I have a Newell with mag scales on my mill as well, they use a little different technology in their mag scales but low maintenance is essentially the key benefit.


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## DarinFred (Mar 21, 2021)

I should be receiving my PM-833TV with the MagXact DRO hopefully in the next week or two.  It’s my first machine and I have a learning curve ahead, but I’ll give me initial impressions once I receive it.


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## davidpbest (Mar 21, 2021)

This is the PM DRO head:







This is the DROPros EL400. Looks identical me except the color:






my guess is they are the same units.  Made by *this outfit*


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## BladesIIB (Mar 21, 2021)

I would agree with David. I just looked at the owners manual for mine and it has EL 400 DRO in the top right of every page.


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## davidpbest (Mar 21, 2021)

PM’s pricing and warranty are better than DROPros for the same units.  DROPros claim to fame is support, and they do post extensive (boring) videos on installation on their web site.  But PM is also known for excellent support.  

I have the EL400 on my PM-1340 lathe and it is functional.  Nothing particularly exceptional about it beyond the fact that it has magnetic scales with sufficiently high resolution on the cross slide - 2 tenths.  What it lacks, that my $2,500 Newall DRO on my PM-935 has, is a feed rate display which I find critical on the mill because I work with difficult materials.


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## cday2021 (Mar 22, 2021)

Rhizome said:


> Hi,
> Has anyone installed the MagXact DRO for a PM-833T?  I think it is a new item from PM, so there isn't much information on it on the website.  I am hoping for some end-user feed back as to the pros and cons vs. other DRO such as DROPro, etc.
> Thanks!


I installed the MagXact DRO on my PM-833TV the other week. 

*X Axis*
Fairly straight forward... I was able to use one of the supplied brackets that came with the DRO. Installed on the back side of the table. Cover went on no problem.

*Y Axis*
I milled a temporary piece to couple with one of the supplied brackets. It's functional, but not final because the current setup will not allow me to install the alumunium cover piece to keep chips off the scale. I will have to mill a custom bracket for this. I instaled this on the right side of the base of the machine.

*Z Axis*
For the Z axis I had to mill a custom bracket. I installed this on the left side of the head. The manual seems to show the Z-axis power feed limit stops installed on the left side of the head, but in my opinion this was the best place for the DRO scale to be mounted. So I installed the DRO scale on the left side and I mounted the Z power feed limit stops on the right side. I had to open up the limit stop switch and flip the switches around because the switch was meant to be installed on the left. Installing it on the right means the switch is flipped upside down, causing the thing to operate backwards. It was easy to open the switch box and flip the two internal switches around so it functioned correctly on the right side of the machine.















(I believe this picture was taken after I had taken the two switches out and flipped them around... that is the switch on the bottom became the switch on the top and vice versa)






cheers,
Craig


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## Rhizome (Mar 22, 2021)

Thanks everyone for your input.  This will be my first DRO.  I will be doing the installation myself and am looking forward to it.  How does everyone manage all the cables and wires that run around everywhere?  Craig's picture of the Z-axis scale shows a black cable that comes out of the switch.  Doesn't that get in the way of milling operation?  

David, is the feed rate a necessary feature for milling stainless steel?  I looked at your Newall DRO install for your mill and read a bit about their scale technology.  Was $2500 the cost of the whole package or just the DRO display (minus the scales)?  I have plan to work with stainless steel in the future.


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## davidpbest (Mar 22, 2021)

Rhizome said:


> Thanks everyone for your input.  This will be my first DRO.  I will be doing the installation myself and am looking forward to it.  How does everyone manage all the cables and wires that run around everywhere?  Craig's picture of the Z-axis scale shows a black cable that comes out of the switch.  Doesn't that get in the way of milling operation?
> 
> David, is the feed rate a necessary feature for milling stainless steel?  I looked at your Newall DRO install for your mill and read a bit about their scale technology.  Was $2500 the cost of the whole package or just the DRO display (minus the scales)?  I have plan to work with stainless steel in the future.



I have used Newall DRO’s on several machines and have come to know they are true industrial quality.  I also like their scale mounting system which is far easier to install than the usual kit of plates/adapters/jack-screws found with the alternatives.  <end of bias blast>  LOL

I went all out with my 935 DRO with 5 micron Microsyn scales on all axis - complete overkill. The $2,500 figure included the three scales and encoder along with the DP700 display - it was a complete kit custom configured to my specs.   A 3-axis Newall DP700 kit with 10micron scales is ~$1,900.  Newall has an entry-level product that is competitively priced against DROPros called the NMS200/300 ($850-$1200) but it lacks the feed rate display function found on the DP700.  Good sourcing/pricing for Newall is https://www.machinetoolproducts.com/digital-readouts/dro-kits/ 

Although the Newall scales are superior to magnetic in terms of imperviousness to solvent and coolant/oil contamination, their highest resolution scale is 5 microns, and not accurate enough for the tolerances I’m after on the lathe cross slide.  If you want to hit tenths accuracy on diameters, you need 1um scales on the cross slide, which is why I went with DROPro’s EL400. The EL400 display I consider “consumer” quality in comparison to the Newall DP700. 

As to your question on milling stainless, the most important thing is consistent feed rates. So having a power feeder will give you far better feed consistency than hand cranking the table feed.  This is also the reason I power feed the cross slide when parting off stainless down to about 4mm diameter, then I switch to very slow manual feed since the SFM is too low for the slowest powered cross feed.  Stainless has a nasty tendency crawl/hop up on top of the parting tool if SFM drops too low, and makes a mess of the parting tool, fracturing the inset and mangling your part.  (At 1/4” diameter, you need over 2000 RPM to hit minimum stainless parting SFM)  

Having a feed rate display on the mill is helpful with stainless or any hard alloy, but it isn’t nearly as important as consistent feed rates, and once you get some experience, you will instinctively know how fast or slow is too much for a given cutting tool.  Limiting the types/sizes of end mills helps in applying your learned experiences.  If you have a feed rate display, it’s easier to just dial in the power feeder to the Feed/Speeds calculator values since none of the power feeders have anything close to a calibrated dial or linear rate changes when you turn the feeder speed knob, but it isn’t an absolute requirement to mill stainless.


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## cday2021 (Mar 22, 2021)

Rhizome said:


> Thanks everyone for your input.  This will be my first DRO.  I will be doing the installation myself and am looking forward to it.  How does everyone manage all the cables and wires that run around everywhere?  Craig's picture of the Z-axis scale shows a black cable that comes out of the switch.  Doesn't that get in the way of milling operation?
> 
> David, is the feed rate a necessary feature for milling stainless steel?  I looked at your Newall DRO install for your mill and read a bit about their scale technology.  Was $2500 the cost of the whole package or just the DRO display (minus the scales)?  I have plan to work with stainless steel in the future.



I'm not quite sure which picture you are referring to? The first and second pictures show the Z axis scale. The black cable you see there is the power to the spindle control box/motor. That's how it came routed with the machine and doesn't present any issues. The last two pictures are the limit stop switch for the Z axis power feed. This has no presented any issues whatsoever, but I do not have much time on the machine yet. I don't see it being a problem either.


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## Rhizome (Mar 23, 2021)

Hi Craig,
I am doing mental installs in my head, but not having the parts available is a bit challenging.  I think it will make more sense once the unit arrives.  I also don't have power feed and their associated limit stops on any axis, so the DRO install needs to be planned carefully to allow for future install of power feed.  I think it would be nice to have both DRO scale and power feed limit stops installed on the same side.  It seems that this will simplify the cable management to some extend.  Thanks for the pictures.


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## cday2021 (Mar 25, 2021)

Hi Rhizome,

I think it will be more work for you to install the DRO and limit stops on the same side as you will need riser blocks to bring either the DRO or the limit stops up from the surface. I haven't had any issues with the cable management with the way I've installed it. I haven't had the mill long, but I would be very surprised if it became a problem. Feel free to shoot me a message if you want more pictures of how I installed everything.

cheers,
Craig


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## Rodneyk (Mar 26, 2021)

Rhizome said:


> Hi,
> Has anyone installed the MagXact DRO for a PM-833T?  I think it is a new item from PM, so there isn't much information on it on the website.  I am hoping for some end-user feed back as to the pros and cons vs. other DRO such as DROPro, etc.


I just received my PM833TV and opted for PM to install the DRO. They install the scales and readers, but the head is an exercise left to the reader. My question is where is a good place to install the head on the machine?  I am cautiously setting up the machine and this seems like a good next step.


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## davidpbest (Mar 26, 2021)

Which encoder head are you talking about. X, Y, or Z?


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## davidpbest (Mar 26, 2021)

Never mind.  You mean the display unit.  Sorry.


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## Rodneyk (Mar 27, 2021)

Shortly after I wrote this I decided to put on my big boy pants and try and figure it out myself.  Looking at a bunch of mills on the interwebs I saw most seemed to install the display unit on the right side of the mill. I went to the shop and started the figure out where I would give it a try. Lo and behold I found two screws exactly where I wanted to put the display arm that were positioned exactly the right distance for the display arm mounting bracket. Apparently PM/QMT had prepped the machine for the display unit after all.


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## Rhizome (Mar 27, 2021)

Rodneyk, can you post more close-up pictures of how PM installed the MagXact DRO?  I ordered it a week or so back.  I am awaiting shipment and have been mentally planning the installation.  Having some pictures of PM's installation for reference would be helpful.  Thanks!


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