"Fred Hayek" wrote in message
...
I want to check the valve guide bores in an automotive cylinder head. I've
seen some small-bore micrometers that cost several hundred dollars. These
are out of my budget. Can I get an accurate measurement with the less
expensive "split ball' type gages, some of which are sold under good names
like Starrett and Mitutoyo, and a regular flat anvil outside micromeeter?
Thanks

Small hole gages are accurate to within a couple ten thousandths in the
hands of someone capable (machinists use them routinely in that capacity).
The big problem you're likely to encounter is elongated or tapered guides,
which can be a challenge to measure.

Harold