Michael G
1st Sep 2017, 11:53 PM
One of the things I'd like for the J&S is the universal head (first picture). A couple of other owners have photographed the internals without disturbing them, and I'm trying to work out what is happening in there. I'm open to other's interpretations -
369732 369731 369730
The second photo just shows some lubrication holes at the rear of the unit and the third photo shows some wicks, so there is a supply of oil going to the phos. bronze bushes. The clear cover at the rear I'm guessing is the oil reservoir feeding the wicks. Obviously you don't want end play in a grinding spindle, so I'm thinking that the two saddles (painted white in photos 2 and 3) are clamping the bushes into the housing and (starting to really guess here) the bushes have a tapered bore which mating sleeves on the shaft run in. The tapered sleeves can be moved apart using a nut and locking washer? (just seen in photo 3)
Another way of getting preload on the bushes is possibly that the thick flange on the RH end conceals a flange on the bush, and the thing in the middle is snugging up to the other end of that bush (that is, the bush is a cotton reel shape). This would mean that the bush on the LH end is just for rotation.
There seem to be two different pulley attachment treatments here too - the first photo shows a pair of lock nuts but the second and third show a grubscrew. (The knurled knob on the far left of the first photo is a tightening method for the collets that can be used - I think the bore is all of 1/2"!) Maybe the locknuts pre tension some how?
Anyway I'd appreciate other's thoughts on how this works (or could work). I did have one owner say that he would strip his down for me and get more detail but that was some time ago and I think it has been forgotten. For reference it is about 3" between the flanges either end of the casting, so not big...
Michael
369732 369731 369730
The second photo just shows some lubrication holes at the rear of the unit and the third photo shows some wicks, so there is a supply of oil going to the phos. bronze bushes. The clear cover at the rear I'm guessing is the oil reservoir feeding the wicks. Obviously you don't want end play in a grinding spindle, so I'm thinking that the two saddles (painted white in photos 2 and 3) are clamping the bushes into the housing and (starting to really guess here) the bushes have a tapered bore which mating sleeves on the shaft run in. The tapered sleeves can be moved apart using a nut and locking washer? (just seen in photo 3)
Another way of getting preload on the bushes is possibly that the thick flange on the RH end conceals a flange on the bush, and the thing in the middle is snugging up to the other end of that bush (that is, the bush is a cotton reel shape). This would mean that the bush on the LH end is just for rotation.
There seem to be two different pulley attachment treatments here too - the first photo shows a pair of lock nuts but the second and third show a grubscrew. (The knurled knob on the far left of the first photo is a tightening method for the collets that can be used - I think the bore is all of 1/2"!) Maybe the locknuts pre tension some how?
Anyway I'd appreciate other's thoughts on how this works (or could work). I did have one owner say that he would strip his down for me and get more detail but that was some time ago and I think it has been forgotten. For reference it is about 3" between the flanges either end of the casting, so not big...
Michael