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- Feb 1, 2018
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Last month I was asked by Tony Baker a Knife maker in Cleremore, Oklahoma to help him to get his machine to cut with-out a taper. I have been down working in Nowata OK for the last 2 weeks. Last Sunday I drove over to Tony's shop and fixed his machine. Along story short he had to remove the head to repair some worn gears last year and the repairmen who did it lost some alignment shims the factory Installed under there when new. Hard to believe a new machine builder uses shims. I didn't believe it, but they are listed inside the parts manual.
Tony was getting a .004" in 4" taper up by the chuck and when he used a small center drill it wobbled when he drilled in center holes. Tony uses the lathe to make bronze flat bearing washers for the pivot of his world famous jack knifes. He said he never does anything between centers. That was lucky as the bed was worn really bad in the normal place. Inside /\ <---- vee under the chuck. The first thing I did was check the machine bed to se if it was twisted. It was and only 2 of the 4 leveling floor screws were touching. I ignored the Tail Stock end of the bed as it was original and he never uses it. I twisted the bed so in the worn end under the chuck so it was .001" co-planer in 8".
Then I had him turn a 2" (OD) x 5" long with 3 1/2 " long sticking out of the chuck. I had him turn the brass down to the OD of the tailstock quill. Then pushed the tail-stock up to the brass and put a mag base and .0005" dial indictor on the compound. I aligned the side pf the tailstock to the side of the brass and it was good at .0005", then checked the top top dead center of both. The tailstock was .011" high or headstock low as that is where the missing shim set. The head bolts down to 2 flats so I put a .010" piece of Argus plastic shim under the head 4 corners on the flats and it measure with-in .001" the same height. Then I had him turn the shaft down to clean up in 3" and it had a .004" taper big on the left end or as the saddle ran into the worn area of the V it turned big.
The head also sets on an independent /\ vee under it plus the 2 flat ways. I had to cut a .008" shim and put under the front outside corner ---> /\ to get it to cut .0002"in 3". He was tickled as he had 3 other local machinist / repairmen try to fix it with-out success. I told him if he ever needed to turn long shafts to buy a new lathe. On a rebuild I would never use a plastic shim. On this repair I did.
Tony was getting a .004" in 4" taper up by the chuck and when he used a small center drill it wobbled when he drilled in center holes. Tony uses the lathe to make bronze flat bearing washers for the pivot of his world famous jack knifes. He said he never does anything between centers. That was lucky as the bed was worn really bad in the normal place. Inside /\ <---- vee under the chuck. The first thing I did was check the machine bed to se if it was twisted. It was and only 2 of the 4 leveling floor screws were touching. I ignored the Tail Stock end of the bed as it was original and he never uses it. I twisted the bed so in the worn end under the chuck so it was .001" co-planer in 8".
Then I had him turn a 2" (OD) x 5" long with 3 1/2 " long sticking out of the chuck. I had him turn the brass down to the OD of the tailstock quill. Then pushed the tail-stock up to the brass and put a mag base and .0005" dial indictor on the compound. I aligned the side pf the tailstock to the side of the brass and it was good at .0005", then checked the top top dead center of both. The tailstock was .011" high or headstock low as that is where the missing shim set. The head bolts down to 2 flats so I put a .010" piece of Argus plastic shim under the head 4 corners on the flats and it measure with-in .001" the same height. Then I had him turn the shaft down to clean up in 3" and it had a .004" taper big on the left end or as the saddle ran into the worn area of the V it turned big.
The head also sets on an independent /\ vee under it plus the 2 flat ways. I had to cut a .008" shim and put under the front outside corner ---> /\ to get it to cut .0002"in 3". He was tickled as he had 3 other local machinist / repairmen try to fix it with-out success. I told him if he ever needed to turn long shafts to buy a new lathe. On a rebuild I would never use a plastic shim. On this repair I did.
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