Black colouring of dial graduations
Continuing to work on a Schaublin 70 I’m reconditioning, it was time to clean up and the add the black to the graduated dials.
There are other ways to come at this, however most involve removing the excess black with abrasives which would damage the plated, “satin finish”, surface
Like everything on this machine, it starts with a dirty mess. Unlike the rest of machine though, there is not enough wear here to need much effort; I just polished the thrust bearing surfaces and cleaned everything up
Cleaning is done with a ultrasonic cleaner with water and some degreaser
after a good soak in the tub, the dial is clean but has no black markings in the graduations/numerals. The chuck is a 4 jaw scroll I picked up somewhere in a Levin 8mm lathe. I’ve got lots of little lathes but the Levin is the only one who’s draw bar worked on the chuck
The black is provided by a furniture repair stick of wax.
The idea is you put the wax to revolving dial and friction warms the surface enough melt it onto the dial
I found warming the dial with an alcohol lamp worked much better
Once the dial is coated in wax, you take a piece of brass with a sharp edge and ‘carve’ off the excess wax. This is just suspension spring from a clock that I had handy
Voila! a small amount of excess wax remained but was easily wiped off with a paper towel. I have to do another today, I may try to get a video
