Information about graduations on cross feed scale
david gregg 1 | 07/01/2022 22:38:45 |
17 forum posts | I have a J&S 540 grinder it is a metric version ,the graduated scale on the cross feed hand wheel is missing ,I have been thinking about trying to make a new one ,but I am not sure how it is graduated or how it is numbered also what the exact shape is does anybody have a similar grinder and and give me any information or even where I could find the missing scale
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Chris Evans 6 | 08/01/2022 10:59:56 |
![]() 2156 forum posts | A Leicestershire company "Andmar" may be able to help. |
gerry madden | 08/01/2022 11:36:45 |
331 forum posts 156 photos | David, as it happens, I have my 540 cross-feed assembly in a thousand pieces right now. I'll make some picks in a couple of hours and put them up here. Gerry |
gerry madden | 08/01/2022 14:16:54 |
331 forum posts 156 photos | David, as promised here's some pics of mine. The 4 key parts (terminology as per Spare Parts Cat.) here are:- 1) Handwheel rim 2) Index ring 3) Washer 4) Cross-feed handwheel In mine the index ring screws to the back of the handwheel rim, with the washer between the two, using 3 x 6BA screws. This sub assembly fixes to the cross-feed handwheel using 3 short caphead screws. My index ring therefore has a plain bore which only spigots onto the OD of the cross-feed handwheel. This is not the same as the cross-section shown in the spare parts catalogue. So I'm not sure which design you have but hope the pics below may help.
Let me know if there is anything else you need to know. oooops.... I have just noticed I have drawn the 6BA tapped holes on the wrong side of the index ring. They should be on the front as opposed to the back as drawn, as is obvious from the photo below the sketch. Gerry |
david gregg 1 | 08/01/2022 19:46:41 |
17 forum posts | Thanks for your photos and your dwg they are very helpful ,the thing that confuses me is that the 6ba screws clamp the graduated ring to the hand wheel I thought the ring would free enough to be rotated to zero,similar to the way the scale on the elevating wheel can be set to zero .Also can you tell what the washer is made from is it metal or fibre I hope you are able to sort out the problem on your m/c you have bigger problems than me so thanks again David Gregg |
gerry madden | 09/01/2022 15:52:05 |
331 forum posts 156 photos | Its funny you should think that David because I was also expecting the index ring to have been adjustable. But there is no suggestion of any modifications subsequent to manufacture and no vacant hole for a locking screw, at least on my parts. If one studies the parts list cross section, it might be that this version has 'adjustability' but since it doesn't show all the screws its difficult to be sure. But it shouldn't be all that to modify the parts to give you this facility if thats what you wanted to do. One can of course lock the fine feed in at zero with any position of the index ring so perhaps this is what one is expected to do if wanting to cross feed by a fixed and easily traceable amount. The 'washer' is made of steel, and is quite soft. I'd actually call it a spacer because that's all it does. But quite frankly I don't know why its there at all. If they had just left 3mm more material on the index ring front face the 'washer' wouldn't have been needed at all.
Gerry |
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