Shars had their branded AccuRemote aluminum scales on sale, $75 for a 6" and 24" shipped. I had to open the read heads and add 0.1uF across the supply rails to make them stable.
I used the L-shaped brackets that came with the scales to mount the 24" Z-axis scale using sections of 1/8" thick 1" aluminum angle from Lowe's. Short slots in the angle gave me up-down adjustment, and the factory brackets gave me in-out. Those screws are threaded directly into the aluminum angle. The scale was mounted with the back facing out. The chip guard is 1/16" thick 1-1/2" aluminum angle, again from Lowe's. I had to trim off enough of one side to clear the bracket. The full 1-1/2" side is flushed up against the back of the bed, and leaves clearance for the bracket mounting screws on the back of the read head. I used 7mm x 10mm drag chain to manage the cables, which are a friction fit to feed them through. I bought a 1-meter length from Amazon, and wound up removing only two links.
A chunk of the 1/8" thick angle was used as a spacer to provide enough clearance for the drag chain. If you don't mind dangling cables you can omit all these fiddly bits.
The TouchDRO app is installed on a 7" Amazon Fire tablet. You have to go through some gyrations to get the Google Play store installed so that you can install TouchDRO. I will leave you to google how that is done.
The X-axis scale is mounted directly above the crossfeed screw by drilling and tapping for a couple of 2-56 screws directly into the end of the scale for a small flat plate that attaches to the carriage. If they were stainless I would sweat bullets trying to do that, because I've had to have broken taps burned out of stainless in the past.
The tachometer function is provided by a cheap IR "Obstacle Avoidance Sensor Module" you can buy from eBay or Amazon for a couple of bucks. I simply spaced 1/4" wide snippets of reflective tape that came with my laser tach equally around the spindle (after cleaning it thoroughly), mounted the module to clear the gear cover using a 3mm screw and nylon spacer, tweaked the sensitivity and adjusted until I got clean signal, and cinched it down.
I used the L-shaped brackets that came with the scales to mount the 24" Z-axis scale using sections of 1/8" thick 1" aluminum angle from Lowe's. Short slots in the angle gave me up-down adjustment, and the factory brackets gave me in-out. Those screws are threaded directly into the aluminum angle. The scale was mounted with the back facing out. The chip guard is 1/16" thick 1-1/2" aluminum angle, again from Lowe's. I had to trim off enough of one side to clear the bracket. The full 1-1/2" side is flushed up against the back of the bed, and leaves clearance for the bracket mounting screws on the back of the read head. I used 7mm x 10mm drag chain to manage the cables, which are a friction fit to feed them through. I bought a 1-meter length from Amazon, and wound up removing only two links.
A chunk of the 1/8" thick angle was used as a spacer to provide enough clearance for the drag chain. If you don't mind dangling cables you can omit all these fiddly bits.
The TouchDRO app is installed on a 7" Amazon Fire tablet. You have to go through some gyrations to get the Google Play store installed so that you can install TouchDRO. I will leave you to google how that is done.
The X-axis scale is mounted directly above the crossfeed screw by drilling and tapping for a couple of 2-56 screws directly into the end of the scale for a small flat plate that attaches to the carriage. If they were stainless I would sweat bullets trying to do that, because I've had to have broken taps burned out of stainless in the past.
The tachometer function is provided by a cheap IR "Obstacle Avoidance Sensor Module" you can buy from eBay or Amazon for a couple of bucks. I simply spaced 1/4" wide snippets of reflective tape that came with my laser tach equally around the spindle (after cleaning it thoroughly), mounted the module to clear the gear cover using a 3mm screw and nylon spacer, tweaked the sensitivity and adjusted until I got clean signal, and cinched it down.
