I love this type of stuff. I am one of those weirdo's who has a bunch of machinists setup as favorites on Youtube. I have not seen the bore dial indicator you use before. Can you tell us a bit more about it? most everyone seems to make due with either a typical dial indicator or a specific tool, such as one use for measuring the bore of a cylinder in an engine.
Thanks Bernice!
5th gear in chuck, set up the 0.0005/div indicator with Noga on axis and level with the bore of the gear. Adjust the indicator point as needed, move the indicator point into the bore into the clean area, adjust the run out using he four screws on the chuck as needed, slide the indicator in/out to verify the bore is on axis with the lathe spindle/chuck and tap gently as needed to get this aligned. Once the indicator moves less than on division on the indicator for both run out and in/out.. double/triple check the set up is secure and nothing will/can move. This is a one time thing, one Ooops, part is wrecked.
Set up the boring bar with the tip of the insert just touching the clear area of the bore, back off the cross feed crank/dial about 0.003" then back up the boring bar into the lumpy area, spin the lathe spindle by hand to check if the point of the boring bar is touching any of the bore lumps, if just clear, back out the boring bar, add 0.001" to the crossed dial, spin up the lathe, take a pass.. Listen/watch for metal removal. If no action, add another 0.001" repeat until contact is made. After the first cut, back out the boring bar, make a measurement. Repeat (in-feed about 0.0005" per pass) until the bore measures the needed dimension. Easy to remove material, difficult to not gonna happen once the material has been removed.
As for indicators, kinda snooty with kind and brand of indicators. Indicators in the shop are Japan (MItutoyo, Peacock), German (Kafer), Swiss (Compaq, Tesa-Brown & Sharpe, Alina)..
2" Peacock indicator in the carriage stop (adjustable)
Best bore gauges made are Etalon (Swiss, measurement anvils are at 135-135-90 degrees allows for measuring out-a-round, only bore micrometers made this way) for manual, Mitutoyo (Japan) for electronic. Without proper measurement tools doing this kinda of stuff is a "lost" guest at best. The internal snap gauge then transfer to a micrometer method has too many sources of possible error, even with the most skilled operator.
As for the lathe, 4500 pounds of Mori Seiki MS-850 (one of Japans finest) -vs- some ounces of hardened steel..
Easily makes a cut that disappears (less than 0.0005") into the clean area of the bore. Then there is a world of cutting tools
and inserts. HSS turning tools are rarely used in this shop, it's always varied grades of carbide or cermet.
Bernice