Visualize how far an ID boring bar reaches into a bore so you can check tool clearance before you run it.
Reference aid — verify before you cut. Thread data per ASME B1.1 (Unified), ASME B1.8 (Stub Acme) and ISO 965 (metric M profile); charts cite their source in each tool. Formulas and data are checked against published standards, but errors and edge cases are possible — always confirm critical dimensions against the controlling standard or a calibrated gage before machining. No warranty; use at your own risk. Tap the star on a tool to favorite it.
Bore & tool
Clearance
The nose triangle is the tool's lead/clearance face; the bar drops until it would foul the bore wall. Enable a cutting-point Ø to check reach against a smaller finished bore. A rough visual aid — confirm on the machine. Tap a value to copy it.