I sold my Grizzly G0704 mill and purchased an Optimum BF30 milling machine (for no particular reason, I just wanted something a little bigger). The very first time I went to add some oil through one of the push in oil fittings, the ball got stuck. I then decided to replace the spring ball fittings with some M10 Zerk fittings (because this was the smallest size the existing approx 8mm hole would accommodate).

The process is very straightforward:

1. Pull the old fitting out using a screw.
2. Drill the hole with an 8.5mm drill (an R drill is only .0044" larger than an 8.5mm drill).
3. Tap with M10 tap.
4. Screw in M10 Zerk oil fitting (McMaster item no. 1105K82)
5. Use oil dispensing gun to add oil (McMaster item no. 1879K48)

I also had to use a 3/4 end mill to make an access on the front of the table to have enough room get the oil gun tip on to the fitting. On the back of the table, I had to make my DRO scale bracket with access holes. I also added some fittings (2 each) to the lead screw nuts. I used M5 pneumatic fittings and 4mm nylon tubing with some split plastic cover for extra protection for the tubing. I made a bracket/port to hold the Zerk oil fittings (running the tubing into the pneumatic fitting on one side of block, thru hole and then Zerk fitting on other side). I also drilled through the saddle to run the X-axis tubing through the bottom with the y axis tubing. Obviously you have to take the table and saddle off the mill and it helps to have access to another mill (I used my G0704 before I sold it).

Here are some photos:

Mill:



Oil Fittings on the Column:



Oil Fittings for the table (upper right of photos) and saddle (you can also see the DRO scale bracket that allows all axis adjustment and Power Table Feed adapter that goes onto the leadscrew):



X-Axis Nut (which shows the routing through the saddle, I added a bolt underneath so the fitting on the underside would not hit the front of the casting when the table is all the way to the front; better to use "Y" fittings and not "T" to maximize oil flow):



Y-Axis Nut (which took some work to get the tubing routed so it would not be in the way of the leadscrew and move freely):



Oil Port with Protected Tubing: