Before I got my Aloris quick change tool post for the little Craftsman lathe I found myself needing a tool post for a boring bar to do a small job I had.
Here is what I did I grabbed a 2 1/2" long piece of 2 1/2" round that happened to be laying under my band saw.
I surarred the ends then un scrolled the jaws from the chuck when I returned them I put the #3 jaw 2 groves out of time then chucked the part again this time it was off center enough to allow me to drill the 5/8" hole for the mounting bolt. I then mounted the part on the compound, returned the Jaws to correct time, chucked up a 1" drill bit and made the hole for the boring bar to mount in. From there it was a simple matter to drill 3 holes to be taped for 3/8 16 TPI
Then I grabbed a 6" long piece of 1018 CR round stock and made my boring bar by milling a 3/8" slot with the top of the slot on the center line of the bar stock 3 holes drilled and tapped in the milled land the outer hole extending all the way through the bar with a long sect screw to prevent the bar from spreading
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