Yesterday was the day to work on coolant stuff.
This mill has a coolant sump in the bottom. It is more or less accessible, through a door that screws on on the side of the mill.
I wired the 110v coolant pump so that it is controlled by EMC. When I press F8 or click on "Flood", coolant starts. The mill has a coolant button, which used to control the pump directly. I did it through EMC so that I can turn coolant on and off via G code. I will later work on integrating the coolant switch with ENC via halui, but for now I disabled it. Since this is a motor, I did not want PPMC to control it, and instead use a DIN rail mounted solid state relay that I had for this purpose.
The content of the sump was about 1/2 water/old coolant and 1/2 tramp way oil. The mill works so that way oil drips down and goes into the same sump, can do nothing about it. My guess is that that stuff was there for very many years.
On the scale of disgustingness, 1-10, it was about 6. Took me about 4 hours to clean up the sump. I put in "Hangsterfer S500", donated to me by Mike Henry (Thanks Mike!), for new coolant. It should last about 2 years or more and does not mind a layer of way oil on top.
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