Reducing backlash in Stanley no.5

Reducing backlash in Y-lever depth adjuster when fitting a thicker blade.
The backlash was already a full turn, but when adding the thicker japanese Smoothcut blade it increased to almost two turns of the adjuster wheel. This is due to the Y-lever's nose being tapered, (well actually shaped like a gear tooth) and the new blade being thicker, thereby moving the chipbreaker slot further away from the lever.
With a Lie-Nielsen or Hock blade the Y-lever may miss the cap iron altogether!
This idea was published in Good Woodworking by Jeff Gorman (GW180 Autumn 2006 - call 0870 837 4773 for back copy). I decided to have a go and take some pictures in the process

This is the subject plane - a pimped-up Stanley 5. The previous owner had fitted a Smoothcut blade, nickel plated the body, and blonded the handles. He had also linished all the plating off the lever cap. I decided to add to the humiliation by blueing the steel on the caps and blade with Bisley gun-barrel blueing gel and filling the nameplate with orange Humbrol enamel. Now suitably tarty, it suffered from too much backlash.

This is the final modified cap iron. The adjuster slot was efectively brought closer to the blade by means of two extra pieces of steel soldered to the back. In fact it was one piece of steel with a new slot cut in. Jeff Gorman made a better job of his, but then I had a camera tucked under my arm at the same time.

The blade is 2.3mm thick. A quick rummage in the Mendology drawer located a mild steel mending bracket of 2mm thickness with enough material between the holes, which would be ideal.

There are two critical measurements - the blade slot width which is about 11mm, and the distance between the y-lever nose and the lateral adjustment lever wheel, indicated by the pencil, which is about 5mm in the working position. Therefore I decided, like Jeff, to have the top end of the extra plate set at 4mm above the slot. Thus the extra plate was to be 11mm wide, and long enough to be 4mm above the slot whilst just clearing the screw thread. On mine that was 15mm approx.

The steel was marked using the scribe out of my combination square. Covering the surface with felt tip pen can help to see the scribe marks.

The piece was sized with a hack-saw...