Simon Williams 3 | 07/05/2020 10:47:04 |
728 forum posts 90 photos | FWIW my take is that you have the symptoms of a piece of debris jammed in the cast iron thread, about 1-1/2 or 2 turns in. Brushing with a tooth brush won't shift it. Cast iron, being relatively soft, will be locally bruised allowing the fleck of debris to nestle in a crevice, jammed in place by trying to force the male over and past it. Borrow a small mirror, go looking down the thread for a foreign object. It will be obvious because it will be a different colour to the adjacent cast iron, having been burnished by running the male thread up to it. Once you've found the bit, it'll take some shifting. Think pointy something with a 90 deg bend in it. It'll be surprisingly reluctant to let go. Don't go cutting or filing, you know it fitted before, it'll fit again but there is a mechanical obstruction. Once you've got the fleck out of the surface of the thread, go looking for another! Good luck HTH Simon |
John P | 07/05/2020 11:03:38 |
451 forum posts 268 photos |
Looking at your photo's the 2nd one down of the external thread it looks to me as if the I took my 7 tailstock apart to have a look more clearly at this and noticed the the external |
Trevor Rushton 2 | 07/05/2020 19:39:35 |
![]() 9 forum posts 5 photos | Dear All thank you so much for your helpful suggestions. You were all correct about the contaminated thread; as I mentioned before it caught me out. Very careful cleaning followed by a variation on the grinding paste method using a small amount of metal polish very carefully as a final clean. I could then screw the cap in by hand - success. So having enjoyed a spell cleaning in the sunshine I took the whole thing back into the workshop for final assembly - 1 turn and that was all I could get. Whole thing out again and another cleaning session- success again. So, most certainly some important lessons there and next time I shall be more careful. This forum has been very helpful so thanks again. |
Michael Gilligan | 07/05/2020 20:51:56 |
![]() 23121 forum posts 1360 photos | Well done, Trevor Thanks for letting us know MichaelG. |
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