Part two of the BMW Boxer exhaust job

In part two I show the machining of the damaged exhaust port. I machined away the threads by boring from the inside, rather than end milling them away, so I could be sure of the way the cutter was working before doing anything vital. Once the threads were gone I recentred on the hole, to be sure the insert bore would align with the port.

[@wtm7554]

Un peu vite, réduit la vitesse avec ce genre de tête à aléser, l'outil peut prendre de l'inertie et aléser à une côte supérieur. Beau taf sinon.

[@chrisstephens6673]

Matthew VIIr Thanks for the comment. I was using the boring away of the thread as a series of test cuts both for finish and size. I made life difficult for myself by working in Metric but with an Imperial boring head but as I was only interested in a tolerance of about plus or minus 0.01mm this was no real problem.😊