I have to admit that I've never really looked at this too closely in the past. Early on I saw that the metric scale on the cross slide hand wheel had an odd number of graduations and forgot about it until just now while reading the thread about handwheels on the leadscrews.

So first off I just assumed that the 12 major graduations were for 1mm each. But then the light dawned that with only 1/8" or 3.175mm of travel that this was not right. So it seems that each major graduation of 10 units should be .25, .5, .75 then 1 and so on up to 3.0 with 7 more small steps more before hitting 0 again. But it's not, it's graduated with 10 small marks of .025mm each then at each of 10 marks there's a major line with a 1 then 2 then 3, etc. So turning in from 0 to get a 1mm depth of cut I need to turn it to "4".

Is it any wonder that I removed the index marker for the metric scale on the dial early on? I likely said "Self, that's rather useless!" and only re-discovered it just now.

For those of you with combo scales is this what you have as well? Is there a method to the apparent madness?

So first off I just assumed that the 12 major graduations were for 1mm each. But then the light dawned that with only 1/8" or 3.175mm of travel that this was not right. So it seems that each major graduation of 10 units should be .25, .5, .75 then 1 and so on up to 3.0 with 7 more small steps more before hitting 0 again. But it's not, it's graduated with 10 small marks of .025mm each then at each of 10 marks there's a major line with a 1 then 2 then 3, etc. So turning in from 0 to get a 1mm depth of cut I need to turn it to "4".

Is it any wonder that I removed the index marker for the metric scale on the dial early on? I likely said "Self, that's rather useless!" and only re-discovered it just now.

For those of you with combo scales is this what you have as well? Is there a method to the apparent madness?

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