I Gaging DRO Question.

[purpleknif]

So last night I was lining up my t'tble. Got everything zeroed. Moved the X and came back. Off .004" Repeat, same result. Move off the other way and come back. Zero. Same every time. Y axis does the same thing. Change direction lose .005". Using an Interapid .0005 indicator. Tried moving sccales by hand. Can get .001" if I really force them. Anyone else have this problem?

Thanks :fan:

 

[Swifty]

I just googled to see what the Igaging DRO was like, you may have some loose screws on the scale.

Paul.

 

[purpleknif]

First thing I checked. They repeat, but differently
in opposite directions.

 

[techonehundred]

Put the indicator on the read head of the DRO and not the table and see if the results are the same. I have them on my milling machine and definitely do not see that much slack changing directions. Also make sure you are not loosing this with you lead screws.

 

[purpleknif]

No slop in the reading units. If you come in plus on the dial and set zero and come plus every time it repeats. If you come to zero on the readouts from the minus side zero on the readout is off .004" every time . Come in from the plus side again and it is zero.
Can't be the screws cuz the readouts are mounted to the table.
I can live with it but it does seem odd. Checked with my JO blocks and they're within .002" over 4". Not too bad for $30.

 

[techonehundred]

That is weird. I have mine off working on an Android display
http://www.yuriystoys.com/2014/07/anrdoid-dro-step-by-step.html

but I will test mine when I get it mounted back.

 

[petertha]

- is there any kind of compensation parameter that is entered into the DRO box?

- assume you are not locking the table at the terminal positions, just observing the readings? (by screwing in the lock/clamp it may be adding a tightening displacement in one direction against dovetail)

- scales are exactly parallel to table travel, not bending through encoder box & encoder box is perfectly aligned?

- if you move this same measuring operation to a different position of the table, say near the outer limits, do you get the exact same results?

whew! (for a guy without a lot of DRO experience, I seem to have a lot to talk about )

 

[purpleknif]

Same every time anywhere along the entire travel in X or Y. No parameters, its just a simple LCD box.