I have just started to assemble my Gearbox for my Comet and immediately hit a problem. The old sprocket was very difficult to remove and is beyond use now. The shaft nut sits inside a recess in the drive sprocket. The nut is two inches across flats and is very difficult to get at. The original sprocket has a recess of 3 inches diameter whereas a new one I have recently acquired has a recess of 2 and 5/8 inches diameter. A very nice man from the west London section has lent me a clever spanner/tool with which to tighten it up properly. However it only fits the original 3 inch recess sprocket and not the new one with a smaller diameter recess.
(Note that my measurements only have the accuracy of a ruler and standard eyesight.)
Possible solutions to tighten up the nut include:
1. Prudent use of a hammer and chisel
2. Acquire a new box spanner that will fit my new sprocket
3. Modify the borrowed tool (with the owner's permission of course) which will severely weaken it
4. Machine out my new sprocket recess to 3 inches
5. Acquire a new sprocket with the 3 inch recess.
Assuming the sprocket I removed is made to the correct dimensional specification does anyone out there know whether it has been drawn under the drawings project and therefore can confirm the correct internal diameter of the recess? Further, does anyone know whether one made to the assumed correct 3 inch dimension been manufactured by the VOC spares company and is available from them?
I have not yet asked the spares company as they usually do not know details like this.
I have also asked the JTAN forum
Thanks
Vic
(Note that my measurements only have the accuracy of a ruler and standard eyesight.)
Possible solutions to tighten up the nut include:
1. Prudent use of a hammer and chisel
2. Acquire a new box spanner that will fit my new sprocket
3. Modify the borrowed tool (with the owner's permission of course) which will severely weaken it
4. Machine out my new sprocket recess to 3 inches
5. Acquire a new sprocket with the 3 inch recess.
Assuming the sprocket I removed is made to the correct dimensional specification does anyone out there know whether it has been drawn under the drawings project and therefore can confirm the correct internal diameter of the recess? Further, does anyone know whether one made to the assumed correct 3 inch dimension been manufactured by the VOC spares company and is available from them?
I have not yet asked the spares company as they usually do not know details like this.
I have also asked the JTAN forum
Thanks
Vic
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