|Nigel Bennett||16/07/2020 09:39:23|
347 forum posts
I've had a Boxford 280 for a while now. When I bought it, the tailstock 3MT bore was badly scored a little way down. There was a reasonable amount of surface left, but it annoyed me and I was concerned that it would not provide the grip for larger sized tools. I contacted Boxford a few days ago to see if they had a spare, but they don't any more. (If I'd wanted a new Myford one, it would have been a lot easier!)
One option would have been to fit a shortened 2-3MT sleeve and permanently batter it into the bore with Loctite, but I had a fair amount of 3MT tooling which would have then been useless.
(One interesting point was that when I had the barrel in my hand, part of the outside diameter hadn't cleaned up properly when it had been originally made. I realised then that the finish-ground taper bore must have been created first and then the barrel mounted on a special 3MT male spigot for the OD to be ground true to the bore. I imagine the keyway was then machined.)
I was therefore left with the option of leaving it or doing something. First attempt was to buy a 3MT finishing reamer. (It was a fairly inexpensive one, and probably made in an extremely well-populated country some miles away from here.) I tried it - and failed to remove any material at all as the barrel is hardened and the HSS reamer wouldn't touch it. My mind boggled at the imagined cost of a solid carbide 3MT reamer...
I did wonder about how I could grind the bore myself, but quite frankly I just didn't have the kit to stand a chance of obtaining a satisfactory result.
I searched on the net for local grinders and sent off several email enquiries. I only got two replies - one apologised and said it was beyond them, and the other said to bring it in and they'd probably be able to do it.
I went over on Monday and it was ready for collection the following day. Brilliant job; they showed me the 3MT test gauge they had used to check it and it blued up absolutely fine.
No connection at all with the company - B Kemp Grinders in Liversage, West Yorkshire - other than a satisfied customer.
Hope the information may help somebody out there with a (relatively) rare problem lathe.
|Michael Gilligan||16/07/2020 10:13:34|
15894 forum posts
Very useful information, Nigel
I have no immediate need, but have duly bookmarked them for future reference.
|old mart||16/07/2020 17:13:15|
|1829 forum posts|
Its nice to find a company which doesn't mind one offs. They would only have to take a couple of thou off, easy for them, but a mighty challenge for the rest of us. That firm is in the same town that Tom Senior mills were made.
Edited By old mart on 16/07/2020 17:24:50
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