Yep, honestly it was only when someone on here mentioned the bit about the spindle axis being Z
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Pm1236 dro install questions
- Thread starter FTlatheworks
- Start date
Have you changed the scale resolution for the X axis in the DRO, it needs to be set to 1.00 uM resolution. Also make sure the scale is connected to the correct axis, and often the diameter function only works on the X axis. The horizontal axis on a lathe is the Z but often the buttons on a universal type of DRO will be Y.
Not yet. Once my work day is over is 40 minutes, I’m going to to go and indicate the scale and set the linear compensation. It’s a 5um scale. What’s the 1um setting going to do?
How is the 5um performing? I have the 5um scales on my mill and they're fine. I'd like to put a DRO on my 12x36 Grizzly.
About to try the linear compensation, this, and indicating it.
Not good, but I’m not done setting it up, so too early to tell.
Alright, I figured it out. When this dro is shut off it automatically switches back to metric. To enable the setup on it you have to switch power on and off, so that was throwing me off. I got resolution set properly. When this dro is set to radius mode the errors stack up quick like most of you have said. When it’s set to linear it is accurate. I think I have it figured out now. Buying a more expensive dro with a better manual might be worth it. This thing isn’t very intuitive, but I have very little experience with dro’s. Now it is accurate to my dial indicator. I will just have to the math while I work, but it will be no different because I already use the dials that way in my head. This will still help me work faster turning things down and sneaking up on dimensions. We will see how accurate it is when actually turning stock down. Now I need to mount the x axis and wire it up to a breaker in the box permanently.
Sorry for the multiple messages that didn’t make sense. I was working on multiple things while typing on here.
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I got the dro installed and working. The z axis with the 1um resolution is working beautifully. The x axis is a 5 micron and it sags in the middle being as long as it is. I’m not happy with the job I did fastening the scale head to the carriage and the scale itself to the bed of the machine. The scale is so long it sags in the center using an .0005 indicator. My cables will move the reading up and down if they’re not secured properly, but it is straight across the length of the bed.
The cable and sag doesn’t seem to be what’s influencing my error. I’m consistently getting .00015 per .100” of an inch. I’m not sure why that’s happening and have tried everything to fix it. Obviously the length of the parts is not as crucial if it’s tenths- thousandths off, but I would like to get it to work better. Any idea why it is consistently off? I get the same error, but not as repeatable when moving back down to a zero set by my dial indicator on the carriage.
Sounds like a metric to inch conversion factor error, are you checking the accuracy against a dial indicator, 123 block or using the machine dials? Is it variable or is it consistent and additive. I had an issue with a mill which use metric leadscrew and inch dials which were off by a similar amount if I recall and it was additive with every inch of travel. You may be able to adjust it out with the scale compensation which typically has a limited range of correction, I have yet to need it with quite a few DRO installs, but these were all mainstream DROs. It might be adjusting the EncLines which typically is the number of lines for a given travel distance or degrees, but not familiar with DRO and deleted the manual.
Yes, I’m checking with a dial indicator. Every tenth of an inch is off by .00015. The scale compensation in the manual wants to use a large amount of travel distance (like traversing the entire scale) and using a formula to determine how much it’s off by. I tried to use an ammount that my dial indicator could read (<=1inch), but it wasn’t working right. Any idea on how to do the compensation accurately?