Figuring hole position tolerance on Keensert installation

[donaldb]

Does anyone have information on the additional hole position tolerance associated with using a Keensert type thread insert?

In other words, if the machine shop can make the outer threaded hole with a position accuracy of .004 inch, what is the hole position tolerance of the inner thread after the insert is installed?

 

[ringman]

There are 3 tolerances that add to this. The orig. hole location, the variation for the tapped hole and the eccentricity for the Keensert itsself. It has been a while,(since I did one of these) but you should be able to ascertain this information and add them together find the resultant tolerance. Assuming you are using Positional tolerance for the mating feature, you will need to specify a projected height for the fastener being used too.