ts39136 wrote:
Just reading through getting familiar with engine issues and came across this!! What kind of tool is this? What is it called? Where can I get one?
How accurate is it in measuring? If I were taking an otherwie good engine apart to "freshen it up", would this tool work to check tolerances and out-of-round situation (followed by plastiguage of course) when lacking a good set of micrometers?
That's a real handy template tool to see if a crank or case has been machined and to what degree. It's just for quick assessment of parts and as such it's a VERY rough guide, it would not stand in for the tools you actually need to build engines.
Get a 6" digital caliper, even the HF one is pretty accurate and very inexpensive, as are their 1",2",3" micrometer set. I make my living with these exact tools and cross-check my mics with my machinist's much more expensive ones, they agree to the 0.0001", and as long as his and mine agree we can collaborate from different towns.
If you want to check bores a set of snap-gauges with your caliper can get you pretty close, but that method takes a lot of practice and still is hard to make as accurate as an actual bore gauge, which you can get at JEGS or Summit for about $80 with resolution to .0005".