Adding a digital readout to the Myford Super 7 Lathe

(click on the pictures to enlarge)

Having decided to add a digital readout (DRO) to my Myford Super 7, I found that there are a number of DROs on the market & many ways to install them. This article describes the method I used for adding the chosen DRO to my machine. This is just one method, but it has proven to be rigid & accurate.

Choosing the Digital Read Out

After seeking advice from fellow members of the Coventry MES & reading an article on the subject in the Model Engineers Workshop magazine (MEW) June 2007, I chose a DRO from Allendale Electronics. Their equipment comprised of a 2 axis display unit, connection cables & two linear glass scales, with their mounting strips & covers. Also included were various brackets, spacing blocks & screws, but no specific mounting instructions.

Installation of the Glass Linear Scale for saddle movement

The glass scale for saddle movement was mounted in accordance with the MEW magazine article, in that it was attached to the rear of the bed using existing tapped holes for the optional taper turning attachment. This mounting proved to be parallel to the edges of the bed, adjustment for alignment with the top face was catered for in the design of the mounting strip. The drive to the scale was achieved by attaching a spacing block & ‘L’ shaped bracket to existing holes at the rear of the saddle. A second bracket attached to the first connected to the moving part of the glass scale.

Installation of the Glass Scale for cross slide movement

The method described in the magazine article, which was to mount the glass scale to the right hand side of the cross slide was rejected. It would have prevented access to the jib strip adjustment screws and the saddle lock. It also restricted top slide travel. After considering various options it was decided to mount the scale to the rear of the cross slide. To achieve this a T shaped length of aluminium bar (from the might be useful one day box) was fitted in a slot milled in the bracket & spacing block previously attached to the rear of the saddle, & bolted to them. The glass slide was attached directly to this. A bracket made from an L shaped length of aluminium (from the same box) was bolted to the rear of the cross slide. The two tapped holes for this being the only modification to the lathe. With a spacing block placed between the bracket and the moving part of the glass scale they were bolted together.

With the display unit mounted on the wall behind the machine I have now put my lathe in the Rolls Royce class.