Carkson T&C Grinder

[mattinker]

"I work on the basis of if it ain't broke don't fix it!"

I was dumb enough to put this in my last post. Well, I made the "small bit holder" for my Clarkson T&C, I went to try it out and guess what, the magic white smoke escaped! "notchy" bearings had gone too far. So I've been obliged to change the bearings and the motor.

I had gathered together the bits to make a two speed set up with a 380volt three phase motor. When I looked more closely, I found a very UN-original belt and pulley set up. I wasn't getting the 4000rpm spindle speed with the pulleys as was.






The spindle had been modified, the threaded portion of the pulley end had been removed, the other end had been shortened by about half an inch and two 1/16" sleeves had been added to accommodate oversize bearings. Fortunately, the original bearing diameters had been left standard so I turned off the sleeves and replaced the with the bearings I'd bought in advance!

2 x'MJ 7/8' or 'RMS7':-
ID=7/8th inch, 22.225mm
OD=2.25 inch, 57.15mm
WIDTH=11/16th inch (0.6875 inch), 17.463mm
I fabricated a pivoting motor mount to accommodate the different pulley sizes




By using a 40 tooth and a 60 toothed pulley on the motor driveing 28 toothed pulleys at 2800rpm, my spindle speed can be either 4000rpm or 6000rpm, well within the limits of the greased bearing specification.


One of the pulleys I turned out the inside to be able to use the other as a hub to fit them to the spindle


I did the same thing with the 40 and 60 toothed pulleys, but I forgot to take pictures!

6000rpm position


Belt change.


4000rpm position

I found the adjuster mechanism difficult to photograph, I placed the pivot at the bottom so that there would not be much of a changing the level of the pulleys allowing the belt guard to work unmodified. The adjustment of the belt uses a split cotter which allows quick "spanner" free speed changes.














Last but not least, the contacter with the red button a knee height!

Yes a lick of paint is in order, but the essential is there! it works!

Regards, Matthew