Just realized a lot of shops are still using the wrong coolant concentration for aluminum, and it's causing surface finish issues.

I've seen it at two different places I've worked at in the last year. They just mix it by sight or guess, usually ending up way too weak, like 5% instead of the 8-10% the brand recommends. The parts come out with that cloudy, etched look, especially on 6061. The foreman at my current spot argued with me about it until I brought in a refractometer I bought for $50. Proved we were under by half. How do you guys check and maintain your mix?

3 comments

3 Comments

the_richard13d ago

Honestly, that sounds like overkill for most shops. If the parts are getting made and the machine isn't overheating, it's probably fine. A lot of old timers just go by feel and their work turns out okay.

the_barbara12d ago

Check the spindle load meter if your machine has one. That's the real tell for how hard it's working, not just the outside temp. Lets you push it right up to the limit without guessing.

cole35712d ago

Refractometer's the only way to be sure... guessing just costs you money in ruined parts.