Coolant and some chips got into my spindle bearings on my G0704.
I am shocked I haven’t heard of this before after taking apart my spindle for an autopsy of the bearings.
I get that there can’t be a seal around the shaft due to high speed but there must be a way to stop coolant from getting in there.
I was so happy with my high pressure coolant, but milling with a 1/8” end mill choked up tight in an R8 collet slotting .375” caused a spray angle that had a good shot into the bearings, they made a bad noise and locked up enough to stall my stock motor, belt conversion spinning at ~4000rpm.
I am going to machine a disc and shrink it on, and put an oil ring behind that, pics to follow....