Measure on the flat side of the tooth. This is the driving side and set the angle of the gauge so that it is a right angles to the surface of the tooth. At the very edge of the tooth it will be almost at a tangent to the circumference but just a little bit more. Do you have a measuring base block with an adjustable rod mount? Old Dan Jones used to set this with a strip of thin paper. The idea was that if you could pass a strip of paper through the mesh of the CW and P without it cutting through the paper the mesh was very close. Depends upon the thickness of the paper. You could try this after you have done your adjustments. I would try using grease proof cut about 2 inches long and 1/2 inch wide.
You could also confirm the conic depth setting using Prussian Blue engineering ink. Oil paint from a local art supply will work well. The print should be evenly spaced along the length of the tooth and at about midway up the tooth flank. With a worn setup as yours is the contact will be quite broad. Wash off residue with turps!
You could also confirm the conic depth setting using Prussian Blue engineering ink. Oil paint from a local art supply will work well. The print should be evenly spaced along the length of the tooth and at about midway up the tooth flank. With a worn setup as yours is the contact will be quite broad. Wash off residue with turps!
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