Dial Depth Gages by Starrett
No. 640 Series (0-1/2")
No. 640M Series (0-10mm)
No. 643 (0-.125")
No. 644 (0-3")
No. 644M (0-75mm)
These depth gages are direct reading tools, referencing from their hardened and ground bases. All bases are 2-1/2" (64mm) long. They are quicker and more convenient to use than any other type of depth gage within their ranges and accuracy.
Electronic Indicators can be furnished by special order.
No. 640 Dial Depth Gages
The contact is slightly up into the base at rest. In action, the inspector sets the contact at zero, which is usually at the bottom of the base. Then the top button is pushed down to contact the work and the measurement is taken.
No. 640R Dial Depth Gages
These gages are the same as the No. 640 except they have reverse movement (no push button) and can easily be used with one hand. Simply set on zero and apply the contact to the work and read the measurement. |
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| Left-to-right: Nos. 640JZ, 643JZ, 644JZ. |
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No. 643 Dial Depth Gage
This gage has a knife-edge base and a needle point contact which has been hardened and ground. The knife-edge base has a cutout so that the conical point can be precisely positioned for close work. Point is 1/2" (12.7mm) long with a 40° included
angle.
In action, the inspector gently pushes the point down to read zero with the base and then pushes down to make the needle point contact the workpiece to take the measurement.
No. 644 Dial Depth Gages
These gages are for longer ranges, and are accurate and simple to use. Put the contact on the work to be measured and push the gage head down until the base stops at the reference point and take your reading. The No. 644 gages feature a Starrett No.
25-441 Dial Indicator and are furnished with three rounded-end contact points to cover the range. Flat end contact points are also available on special order.
The zero setting can be checked with the (shortest) contact in place by pushing down on a flat surface. |
Starrett Tool Index 
