Yeah I think you are right. I think I also doubt my ability to get them right, so that everything is right on when they are mounted. Will give it a shot of course.
And thanks.
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Aligning A Cheap Chinese Dividing Head/rotary Table Combination
- Thread starter CarlosA
- Start date
Yeah I think you are right. I think I also doubt my ability to get them right, so that everything is right on when they are mounted. Will give it a shot of course.
And thanks.
- Joined
- Jan 22, 2011
- Messages
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Don't assume the table slots are all that accurate. Stick an indicator on the side and run the table. You might be pleasantly surprised, or dismayed. If you want or need to work to 0.001-0.002 accuracy, you'll indicate your part or fixture anyway. The keys are for production work, typically less demanding.
Yet another good point, lol. I just really hated dialing in the dividing head every time I had to set it up, since i`m making many gears. I will try & see how accurate the slots are, I didnt even consider that they may be rough cut.
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- Jan 22, 2011
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It is possible to skim one side of the slot, and then push your keys against it. You won't be able to cut the entire length, but that's something you may can live with. The you could make some good step keys to fit. I still would bet you'd want to indicate your fixturing in, but it would get you pretty close.
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- Jul 2, 2014
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Keys are just little chunks of steel. Cut them until they fit nicely. If by mistake you cut too deep, put them aside and make more, until they are correct. Then round all the corners and edges so they do not dig into the table and gouge the table slots. Use socket head cap screws, counter bore so they sit below the surfaces, so you do not scratch your table. I make them just loose enough to fall into the table slots easily, which leaves enough play to dial the table and tail stock in if the work requires it, otherwise, bolt it down and git-er-done.
So I swept the table with a .0005" test indicator and it does stay between 0 and .0005" the whole way ... it moves a bit from catching on rough metal, etc but as you lock the table in each spot it drops right back to that tolerance. I was kind of surprised really.
I will do this, I was thinking it can be the shape of a T but its not necessary - can do the shape of an L so that one side can be used for getting everything dialed in in the vise. Worst case i`ll lap it in the rest of the way, spend some time on it once so it drops in every time.
I will do this, I was thinking it can be the shape of a T but its not necessary - can do the shape of an L so that one side can be used for getting everything dialed in in the vise. Worst case i`ll lap it in the rest of the way, spend some time on it once so it drops in every time.
