Thread: Soft Jaws.

Hi Guys,

Following on from making repairs to my milling machine, I had to cut a recess in the lathe soft jaws to hold the bronze disc for boring the bearing surface. Since I had in the past used aluminium discs screwed to the face of them, I decided to make some proper ones that could be easily and cheaply replaced. Bottom two pictures.

They are 40 mm long and 15 mm square aluminium, drilled and countersunk to take M6 hex socket CSK screws.

Mill Bush_18-02-2020.JPG

This is a picture of the replacement bush in bronze. The original one was way over size and had allowed the down feed shaft to drop enough so that the fine feed gears no longer meshed. The new bush lifts the shaft by about two millimetres.

As you can see in the picture at the top, I slipped with the graver when marking the reference line. I used red wax crayon to fill in the mark and make it more visible

18-02-2020-003.JPG 18-02-2020-002.jpg

Because I couldn't get the piece of bronze in the chuck originally, because its diameter was too large and not thick enough to hold. I drilled a 1/2" hole in the centre, mounted it onto a mandrel held in the lathe chuck and used that turned to outside down to the correct 50 mm diameter and face off both sides to give 9 mm thickness.

I swapped the chuck jaws for the steel soft ones that I had. I then turned a recess in the face of the soft jaws to hold the bronze ring. You can see the 5 mm deep recess behind the new aluminium jaws that I made. Then I bored out the centre to suit the down feed shaft size of 22 mm. Clamping the old and the new bushes together in "V" blocks, I spotted through and drilled M4 clearance and then counter bored to suit M4 cap screws.

Good one Baron I always like it when "there is more than one way to skin a cat" procedures are used