Way back in 2009 I wrote about my Poor Man's DRO on the Mad Modder site...
http://madmodder.net/index.php?topic=781.0It worked 'quite well', but not perfect. Less than optimum accuracy due to the use of flexible cables and eventually almost total failure due to the plastic covering of the steel fishing lines getting rubbed off and jamming in the cable sleeves.
There had to be a better way....
DRO in cross slide by
aardvark_akubra, on Flickr
... and they dont come much easier than this!
I bought a cheap DRO scale with a remote display, I drilled a hole in the end of the scale and tapped a 3mm thread in the side of the cross slide feed nut. There is just enough room for the scale under there. A simple bracket was made to hold the sensor head at the rear of the cross slide and it was ready for testing.
Of course using a scale like this reads in radius rather than diameter and it remains to be seen if the scale is adequately protected under there, I think it will be especially as I do not use flood coolant and the oil on the dovetails and feed screw is not exactly being thrown around.
It needs something fixed to the rear of the cross slide to protect the sensor and the exposed end of the scale but I will give the scale a bit of a trial before drilling holes in the cross slide.
