Gulp!!! Thank you, I am not sure what to type. Thank you flguy, and craigb1960 and Mark. Mark, I hope you don't mind me using you design?
I have done some more work but haven't got myself a new camera yet, I will sort that. I have some cheap cutters from ebay Chinese, cheap and cheerful,
but only 22mm long so I was not sure I could cut all the way through the barrel so after finishing on the lathe I decided that rightly or wrongly that was the next operation. The cutters are end mills so I drilled 8mm holes through the barrel at the limits of the slot to half way through the barrel and then used the
10mm cutter till it started to wear down the plain portion of the shaft. Then used a 12mm cutter to a depth of 15mm then continued with the 10mm cutter to the middle of the barrel. I have a er16 collet chuck in the mill with the cutter a long way out I thought if all goes pear shaped the I will have to buy a longer cutter and have another go later. I have been buying cheap cutters on ebay at £6 for 5 cutters 12mm 10 8 6 4mm for a few weeks one set each week that includes post and inport, i have about 10 sets so if I break one what the heck. I got to the middle, heart in mouth, no probs, and the cut the 2 flats for the
worm spindle at the sides of the main slot. These flats were to be the reference to cut the slot from the other side, I turned the barrel over but I have no parallels so I used 2 6mm hss lathe tools that I had that were the same size as each other, I have 6 of them but only 2 of them are the same size. I wiggled
all in and started again cutting the slot from the other side after about an hour and 3 cups of tea later the slot met, well nearly but not bad.
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