“I figured I'd share something I put together with the lathe and milling attachment since your site has been such a huge source of inspiration and ideas. I wanted something I could mount a dial/digital indicator to so I built that first. Then as I used it I figured it would be really simple to make an attachment that would add functionality as a cross slide stop- something I found myself wanting quite a few times.
I overbuilt the indicator holder with a too thick piece of 6061 since that was the only stock I had at the time. It could be made much thinner and still work. The 4 holes allow the indicator to be moved forward and back as needed and the stop that mounts to the carriage can also be moved to allow for the 1 inch travel of my indicator. After much frustration trying to tighten the indicator holder to the carriage with the limited clearance for the allen wrench I ended up silver soldering it into the cap head screw, problem solved. If I had it to do again I wouldn't make the holes for the bolt that tightens to the indicator all the way through- it would be much more convenient for one side to be tapped instead of using a locking nut.
Also of note are the pieces of brass on the stop holder. This is because I'm still way too inexperienced at machining and I took too much material off. A little epoxy and shim stock later and it works just fine. The half round cutout on the bottom rail of the stop allows enough clearance to remove it without completely removing the bolt, but it also makes sure the stop won't slip backwards for any reason. The set screw for the stop is just something I had laying around and I'll probably make a prettier one if I ever end up making a knurler.”