How do you use a Sine Plate?

How do you use a Sine Plate?

Query by Jim: How do you use a Sine Plate?
I need to have to know who to use a sine plate to verify the right angle on a machined portion.

Very best answer:

Answer by Steve C
We are producers of quite higher precision machine tool slideways and use sine bars all the time to accurately set and inspect the ground angles.

The sine bar has two cylindrical rollers on its base and these are at extremely accurate centres. The ones we use are either 5″ or ten” apart. I guess that there are metric ones offered also.

You location one roller on a surface table and set the height, and therefore the angle, of the other roller utilizing slip gauges.

The distance in between the rollers is now the hypotenuse of a right angled triangle and the rest is down to simple trigonometry.

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