Why does corrosion occur in alloy aluminum?

[@lwilton]

A great job as usual, and also interesting information to know!

[@radboogie]

Do you have to change out the cutting fluid for different types of metal?

[@VulcanBomberxm655]

No

[@CraigLYoung]

Thanks for sharing 👍

[@brucejenner4800]

I thought kerosene was the coolant of choice for aluminium?

[@shug831]

A couple of witness marks to show its the forging that was undersize.😉 Used to have similar problems with nimonic steel rings when roughing.

[@peachmelba1000]

If I was to start a shop, I would specialize in processing large forgings. Not simple work by any means, but far less hand wringing than making ultra high precision production runs or one offs. I worked for shop that did aero and oceano parts, often in the thousands per job, and the tension was unrelenting lol

[@shug831]

@@peachmelba1000 know what you mean. I worked with RR and the tensions of working on high precision components for aircraft engines against the clock was a killer.

[@peachmelba1000]

@@shug831 Picture this (this nearly caused me to quit): 4500 inconel rings, 17" OD, .25" thick, 16.25" ID with an ID groove .040" deep x .015" wide. Oh, and max run out, like +- .0025 I still have bad dreams about that run haha Edit: Yes those are the actual dims. I'll be babbling them in the nursing home in about 30 years haha My only clear remaining memory 🤣

[@bigbattenberg]

@@peachmelba1000 What a great story and you tell it with such humor! Thanks.

[@theessexhunter1305]

Oxygen..........is the culprit