The vertical arm held roughly in position.
Clearance is ok between arm and plastic cover part of mill/drill.
I did a bit of judicious filing on front of quill arm to get it square to table and to get it pretty flat and true in the horizontal as well.
I worked out where the holes had to go in the arm and drilled and counterbored for M6x1 socket head cap screws. Here the casting is clamped up square to table ready for drilling and tapping of first hole into the casting at bottom of quill.
The hole in the Aluminium casting is 6mm diameter so I spotted through with 6mm drill then drilled for tapping size to depth. I have an ink mark on tapping drill to show correct depth. After fitting first screw I squared the casting up again then tightened screw and then drilled and tapped for second screw after spotting with 6mm drill as before.
The rectangular Aluminium casting has been milled a bit like a Z shape. I marked out and drilled 3 holes for the scale head.
I've cut a 6mm diameter slot in the Z piece and made a suitable pin to suit, I also machined a M6x1 thread on the pin. The vertical arm has been drilled and tapped to suit. I also cut a screw driver slot in the threaded end of the pin so I can tighten it nice and tight from behind, I also put a drop of Loctite thread lock on it.
All assembled. The slot removes any chance of the rotational slop movement of the quill putting force on the digital head/scale assembly. The spring holds the scale head upwards against the bottom side of the pin so that as that whole lot moves downwards or upwards the digital head is always held to the underside of the pin. The scale head moves quite freely and the spring is a rather strong little bugger so it always holds the digital head against the bottom side of the pin. Apart from the pin there is no contact between the vertical arm and the Z shaped piece.
After a bit of fine adjusting of the scale so it's true to the quill travel all works very well. In the side of the mill drill head there is a screw with a plain bit machined on the end to act as a "key" to the quill. I replaced the original with one I machined with a plain section that was a closer fit in the keyway in the quill, there is now much less rotational slop in the quill.
I got ideas for mounting of the digital readout from my brother in law, Wayne. He prefabricated his mounting plates from Aluminium plate, his side plate was mounted using the two existing cover screw holes(enlarged). He also used a C shaped spring between the vertical arm and the plate on the back of the scale head, whereas I went for a coil extension spring mounted out the front. My appreciation goes to Wayne for his mounting and slot ideas. There are 3 pics of his Digital Scale mount below.
This should be a new window, minimise or close it to return to Home Page or press