Looking for holtest/bore gage...help - Range of hole measured 3.6 - 4.0"

[Timmer]

Trying to locate a gage like the one pictured here. Range of the hole measured is 3.6-4.0". THere is no manufacturer or ID at all on this and the gage is over 10 years old. Any help is greatly appreciated. Trying to mimic the current model if at all possible. Thanks to all

Tim

 

[Wes Bucey]

Bore micrometers (actual reading instrument versus comparative reading of a "gage")
There are several considerations you want to consider as long as you are buying a new (or used, calibrated) one:
Here's one type:
https://www.mitutoyo.com/catalog/pdf/N-26-29.pdf

Depending on your quantity of pieces to be measured during a shift, you do want to consider using a jig to hold instrument steady in relation to workpiece.

Some digital readouts (like the one in the catalog page) can directly input to a computer for SPC charting - saves time and eliminates some transposition errors in posting data readings.

My advice - depending on amount of usage, go with big brand names (Mitutoyo, Brown & Sharpe, etc.) because repair parts and service are available to extend the life of the instrument. Depending on workpiece material, get carbide faced anvils.