Is the PM Magxact MX-200L much better than the standard PM optical dro?

Bryan40g

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Like the title says, is it much better? If so, what is better about it? I mean besides the nicer display and less fragile scales. Guess I’m asking more about the functions which I know basically nothing about. I just got my lathe a few months ago in October and have really only used the dro once or twice while making a special bolt for my QCTP.

I ask because I just bought the PM MX-200L. I wanted the MX-100L but they are back ordered and said what the hell its $200 bucks for something I really don’t have to have. Why not. I say I didn’t have to have it because my 1228 lathe came with the optical dro installed on the machine. I was advised when I purchased the machine to get the dro being that I’m new to machining and using a lathe. It works very well but ran into problems due to the length of the scales and I’m too scared to try and modify them shorter like I’ve seen some online do.

So I got the Magxact dro after learning it’s got a smaller form factor and I can easily shorten the scales which would be very helpful for the upgrades I have planned for it. Thanks Dave Best for your picture album of your 1340gt Best Jacobs edition. I’m planning to copy quite a few of his well thought out upgrades on his machine.

So other than the much nicer display and being lathe specific, if anyone has the same or similar Magxact dro or on theirs I’d like to know how they like it. If they can compare against the optical dro’s or if their only experience is with the Magxact dro. Looks to have more features. Thanks fellas. Y’all all have been very helpful to me since I joined.

oh and if this thread is in the wrong place I do apologize. Happy to move it if needed.
 
On a lathe you are basically reading the numbers and not using most of the features of most DRO's. What I do not follow is that you can easily order a new glass scale to almost any length in 10 mm increments, they are also available in 1 micron slimline (GS30/GS31) which are smaller. One issue if I recall with the 1228 is that the gibb adjustment is on the tailstock side so the scale is often mounted on the headstock side. This exposes it to being hit by the chuck and also more swarf.

Function wise the MX100L and MX200L will both readout numbers and have similar features, I have the previous model of the MX200 on my mill and it is much nicer than the MX100 which I have used on other peoples machines. That being said, if you already have a DRO and all you need is a different scale, I would just get a new scale. My mill uses all magnetic scales, my lathe I have both glass and magnetic scales. They use the same signaling but sometimes the pin connections may be different. The DRO manual usually describes the pin connection and you need to check that against the glass scale. OM/QMT should also be able to get you a different length scale.
 
On a lathe you are basically reading the numbers and not using most of the features of most DRO's. What I do not follow is that you can easily order a new glass scale to almost any length in 10 mm increments, they are also available in 1 micron slimline (GS30/GS31) which are smaller. One issue if I recall with the 1228 is that the gibb adjustment is on the tailstock side so the scale is often mounted on the headstock side. This exposes it to being hit by the chuck and also more swarf.

Function wise the MX100L and MX200L will both readout numbers and have similar features, I have the previous model of the MX200 on my mill and it is much nicer than the MX100 which I have used on other peoples machines. That being said, if you already have a DRO and all you need is a different scale, I would just get a new scale. My mill uses all magnetic scales, my lathe I have both glass and magnetic scales. They use the same signaling but sometimes the pin connections may be different. The DRO manual usually describes the pin connection and you need to check that against the glass scale. OM/QMT should also be able to get you a different length scale.
Yeah I was also hoping PM could help with the pin connections and I even emailed DRO PROS with the same questions. Heck I was even willing to purchase new magnetic scales and both told me their were differences and that I could not do that. I read the same about different pin connections swapping 2 wires but I a novice at soldering. Scared to break it. Normally not scared to take anything apart as I’m a diesel mechanic and can rebuild just about anything that comes my way with no issue.

Didn’t realize I could purchase custom length optical scales in fact never even thought about looking but then I could possibly still have the same issue with wires being soldered to different pins or something.

Yes I had the dro pre-installed which I would never do again and they installed the saddle scale right below the adjust screws for the back side saddle gibs. No way I’d ever have been able to adjust them. The cross slide scale is also a pain as the head of the carriage lock is practically touching the blue squeegee strips of the optical scale. Lastly the cross slide lock and gibs are totally inaccessible. Thanks to Dave Best and his idea of mounting the across slide scale with spacers to access the lock nuts and with the slim magnetic scale I can easily shorten I think I shouldn’t have to much of a problem.

When the lathe arrived I had read that I need to disassemble as much as I was comfortable to clean, debur and inspect which I did. That forced me to remove both dro scales and reposition them both after cleaning and adjusting. Something I did not want to do as I figured it was a precise type installation to get correct for it to be accurate. Defeated the point of paying for the installation completely. I don’t blame PM as it’s not their fault but the installation prevented me from important adjustments that I would absolutely have to make. Oh well. I have had the cross slide off so many times I can dial it in with a .0001” indicator in a few minutes. Still getting the hang of adjusting the gibs. Like the manual says trial and error.

One major backlash issue I was having is cross slide movement on the dro while cutting a part. Think I got that figured out now tho.
 
I rarely adjust the gibbs, like every couple of years, so I would not go to extreme lengths to have access to the adjusters if all you need to do is remove the DRO scale. I have seen them placed on either side of the cross slide. Most of the glass scales will have similar pin outputs, any you do not need to resolder pins, there are male to female pin adapters and you just swap the in/out pins. They should be able to tell you the glass scale that was installed, it is lame if neither DroPros or QMT can't figure out that out for a glass scale. Magnetic scales sometimes there can be some issues, I have an Easson 12B on my lathe and use Easson glass scales and a SRA magnetic scale on the tailstock. I verified compatibility and pin output with them in advance. DRO UK sells the ES-12B or C with complete magnetic scale packages, which numerous people have purchased. There are also eBay sellers that sell glass DRO scales and will match the plug/pin output to the DRO manufacturer. There are options, but if the MX-200L is already on its way, I think you will not be disappointed, they are very nice units.
 
Yeah I didn’t figure the gib needed to be adjust frequently. It’s just that I’ve never done it before and disassembled everything since it was slathered in cosmoline or whatever it was and had to do it when I went back together. Let’s just say I did it over and over and over trying to remove the slop and adjust them correctly. Kept seeing movement during cutting on the dro monitor and not getting very good consistency when trying to gauge the accuracy of the dro. Couldn’t even hit a target dimension. I believe it was all because of my incorrect adjustment of the cross slide gib. Think I have it right now. I think. I about .0001” on my indicator when I apply psi side to side. And it still travels fairly smooth.

I agree it was lame neither could assist me with the actual differences of the scales other than to say they were different encoders I think is what they said. Oh well, I’m over it and looking forward to a much smaller shorter scale to deal with. It looks very nice. Would have been happy with MX-100l but on back order so lucky for them and me I guess. Says 7” screen guessing that’s probably diagonal. Those screen protectors you mentioned look big enough to get several or a couple out of each.
 
FYI, unless you have a cross slide lock, it will move. When mounting the DRO scales they are often covered, or limited access. It is a balance of getting the gibbs tight enough but not so tight to bind. But over time they will wear a bit and you will get some movement. I made a cross slide lock that bolts to where the follow rest is mounted, I use it all the time when I am getting to final dimensions.
 
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