# Tail Stock Dro On A G0709 Lathe



## BGHansen (Sep 10, 2016)

Sold some stuff on eBay and bought a DRO for my G0709 lathe, that installation is in another thread.  At the same time I “invested” a whopping $25 from TPACtools.com for a tail stock DRO.  Here’s the boring, long-winded details of my installation . . .  sorry for all of the photos, but as the saying on this site goes, it didn’t happen if there aren’t photos!

I decided to mount the scale at a 30 deg. angle from flat, just makes for easier reading.  Mounting the DRO involves making a bracket to mount on the quill and a second bracket that mounts the read head on the tail stock body.  In use the scale moves with the quill, the read head is stationary.

I used a piece of ½” thick aluminum for the quill mount.  It’s a ring ½” wide, OD/ID will vary depending on the diameter of the quill (1.655” on my lathe).  The ID was bored 0.003” larger than the quill for a slip fit.  Two “ears” are on opposite ends; one for mounting the scale end bracket and the other for a pinch bolt.  Could have done it with just one ear, but went with two.

Dykem’d the adapter and started with a ½” hole on the drill press.  Then went to the mill for drilling/boring to size.  Used my co-ax indicator to set the bracket in line with the mill spindle.  Wow, didn’t take any pictures of the actual boring head work!  Made passes of 0.010” until the hole was to size.

Work was removed from the vise and rotary table set in place.  Centered the table under the spindle by sweeping a shoulder bolt head screwed into a center plug on the table.  Then set the bracket in place and centered it on the rotary table with many taps with a brass hammer sweeping the inside bored hole.

Really nice to have a DRO on the mill.  Zero’d the readout with the spindle over the center of the bracket, and moved to the side the radius of the center hole, another ½” for the width of the adapter ring plus another 0.125” for the radii of the ¼” end mill.  Then another 0.010” to allow for a final clean up cut.  Plunged the 4 end holes and cut the outside of the ring stopping at the end holes.

The vise went back on the mill and the sides of the two ears were cut.  My dad was a high school shop teacher; he taught me to align the work’s layout line to the vise jaw with an adjustable parallel.  Milled the mounting ears flats next.

Set the end bracket of the DRO scale on the mounting adapter and marked the center of the hole.  Back to the mill for drilling/tapping the scale bracket mounting hole.  Also drilled/tapped the pinch bolt hole and cut a 1/16” slot with a slitting saw.

Now onto the DRO read head mounting bracket.  It’s a block of aluminum with the face cut at a 30 deg. angle.  I started by facing the surface, then cut the sides for the two mounting ears.

The scale was set parallel to the tail stock body by setting an adjustable parallel under the scale at the quill bracket end, then moved the parallel to the far end of the scale.  I realize the top surface of the tail stock is a fairly rough casting, but there is some “forgiveness” in the scale.  The wedge read head bracket was set under the head mounting bracket and a line scribed onto the aluminum block.  I’d purposely made the block too deep for final sizing.  The block is very close to an oiler on the tail stock, didn’t want to cover up the ball oiler with the bracket.

Back to the mill and final sizing of the wedge bracket.  Also milled a couple of mounting slots for attaching the bracket to the tail stock.  Drilled/tapped a hole on the face of the wedge bracket for mounting to the read head bracket.

Well, I made an “engineering change” before drilling the two holes into the tail stock for the wedge bracket.  I was a little nervous about drill directly over the quill, only have about ½” of material in the casting above the quill.  I’d really hate to drill into the quill!  So, extended the slots on the read head wedge bracket and moved the two mounting screws away from the center of the quill. 

Used a Dremel cut-off wheel to cut the scale to length and screwed everything in place.  Works great!  On to the next project!

Bruce


----------



## JimDawson (Sep 10, 2016)

Nice job and write up!   Thank you!


----------



## Cobra (Sep 10, 2016)

Great job!  I have one of the DROs sitting in the lathe drawer waiting for me to make a decision on how to mount. 
I was looking at face mounting to the end of the quill but this will work much better. 
Thanks for the ideation!


----------



## dieselshadow (Sep 10, 2016)

Once again Bruce, most excellent work and much appreciated for taking the time to document what you did. That doesn't come free.


----------

