Discovered a coolant ratio trick that cut tool wear in half

I run a Haas VF-2 at a small shop in Cleveland and for months I was fighting with tool wear on 6061 aluminum parts. The inserts kept chipping after about 40 parts and I was ready to blame the supplier. Then an old machinist stopped by to drop off some tooling and noticed my coolant looked thin. He told me to get a refractometer and check the mix ratio. Turns out I was running at about 3 percent concentration when I should have been at 7 to 9 percent for aluminum. After I fixed that last month, the same inserts are going 80 parts before showing any wear. Has anyone else seen a big improvement just from dialing in the coolant mix?

2 comments

2 Comments

holly_walker761mo ago

My refractometer was off by half a point and I wasted a week blaming the tooling.

miles721mo ago

48 years ago I was doing a rush job on an old Bridgeport and the coolant smelled like rotten eggs. Turns out my buddy had topped off the tank with pond water from his farm because he was too cheap to buy distilled. Whole shop smelled like a swamp for a week. The tools actually lasted longer though. Something about the bacteria eating away at the gunk. Weird stuff.