One of these:
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1" BSPT on the outside and 1/4" BSPP inside, its for a water drain tap on a Lister D.
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I offset the tailstock behind center and turned it between centers to get the taper. The original plan was to just drill and tap a 1" iron stop plug but I couldn't think how to hold it in the chuck to drill it (Can't fit a 12mm drill in my pillar drill) so I went for the easier option.
The ends of the threads need dressing with a small file but I'll leave that for my dad when he fits it.
To drill a 1" iron bung in the lathe you could wrap the threads with a few turns of insulating tape or a better method would be to use a 1" barrel socket gripped in the lathe & screw the bung into it.
But well done for making a nice brass adaptor, you did know that you can buy them?
