As pictured, my harbor freight mini mill converted to CNC, I want to add a coolant mist sprayer for my machine but I'm afraid of rust on my ball crews, I installed a plexiglass shield in-between the motor and the column to protect my Z ball screw and ball nut from any flying chips, I also installed a piece waterproof fabric to act as one large bellow to protect my X/Y stepper motors from any future coolant.

Any ideas on what to use as coolant on the cheap? And I've been using a heat lamp 24/7 to keep any and all humidity down to prevent any rusting. Any advice or opinions will be nice.

Thanks.

Since there's no real place to ask this, I need a metal coupler that's 2" long and with a 8mm bore, only one I can find is 1.4375in long and made out of plastic