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Just got a 7X12 lathe. The hole through the chuck is smaller than the hole through the spindle. Can this be bored out to match the spindle bore? Seems like there would be a lot of waste using short pieces of stock in making reel seat parts. (David Dziadosz)
A year ago I bought my 7x12 lathe and I spent a lot of time monitoring the YAHOO mini-lathe group. As I remember they were passing around a reamer to do this operation. Also look at Wholesale Tool for 4" 3 jaw chuck that will bolt directly to your spindle, if your spindle has 5 holes. This chuck cost $36. and has a 7/8 hole. My spindle had three holes, I had to drill 2 additional holes. One of our list members sent me a template to layout the new holes.
Also check out Little Machine Shop on the web for all sorts of mini-lathe parts and tools. The owner (Chris?) is a great help if you have questions. (Bob McElvain)
First calculate the amount of stock you will need. For example, I have a 7/8" rod that I make the threaded ring, sliding ring and threaded 'nut' from. I decide the length of each, add them all together, add the parting tool width and cut a piece this length. I first make the nut, part it off and drill/bore the remaining piece to desired dimensions. For finishing the sliding rings, get a machinable expanding arbor. Machine the outside diameter to the inside diameter of the part(s) you wish to hold. If you are making the rings with different outside diameter, make the arbor for the smallest diameter part. After the first part has been finished, turn a sleeve (brass is good) with the inside diameter of the arbor and the outside diameter that the ring is to be. Hold the ring part in the jaws and bore to the desired diameter, mount it on the sleeve and mount the sleeve on the arbor. Finish the outside outside of the ring. No waste except the normal machine swarf. (Onis Cogburn)
 I have a question for the lathe users out there. Who has experience using a boring bar to true up the jaws on their chuck? The outer set of jaws that came with the 4" 3 jawed self adjusting chuck I bought are a tad off center and I need to true them up. The chuck itself is running true so it has to be the jaws. Yes? I have verified that the jaws are in the right slots as well.
I read an article, back when I was looking at lathes, about truing up the jaws with a boring bar instead of a tool post or tail stock grinding attachment which I don't have. I can't find it now, of course, but I know it's been done. Feedback appreciated. (Wayne Kifer)
I wouldn't recommend a boring bar for this. On my older chucks that were worn, I used a round grinding stone that comes mounted on an steel shaft. This was for regrinding Magna-bits I think they were called. It is a very hard stone. I mounted it in the tail stock chuck and brought it into the jaws of the chuck. Use a lot of oil, run the lathe on a moderate speed and close the jaws, until they just touch the stone. Run the stone in and out of the jaws, using the tail stock hand wheel. Then tighten the jaws slightly, then run the stone thru the jaws again. Do this little by little, until the jaws are true. On older chucks, you will never get them dead nuts, as the scroll part of the chuck and the jaws where they fit the scroll, are usually worn and there isn't much you can do for that.
But, by using this method, you should be able to get them within a few thousands. (Dave LeClair)
This is a new chuck but I don't see why that wouldn't work on it as well. I assume that you feel that contact with the stone will force the jaws outward as far as they will go thereby seating them while in an open position. Sounds worth a try. (Wayne Kifer)
The instructions that came with my lathe said to use a boring bar to true the jaws. However, the jaws were so-called soft jaws (aluminum). I was to close the jaws on a washer which was supplied. Put the washer at the rear of the jaws, then turn with a boring bar. I took light cuts, and it was kind of bumpy, but it worked well. (Neil Savage)
Yes, I found that truing up the jaws this way, seemed to work the best for me and it took out most of the run out. Other than buying an adjustable six jaw chuck for $1,000.00, like I did a few years ago, this is the next best thing. (Dave LeClair)
I would suggest that truing up you chuck with boring bar will work. However I would also suggest your align your lathe prior to truing up the jaws. There is a procedure for aligning the tail stock with the jaws. I don't have the article on the tip of my tongue but it is available. Once this is done, you can true-up the jaws with no problem. After alignment, I also bore-out my head stock & chuck to accept .780" on my mini lathe. I made two fixtures to assist in aligning the head stock to the tail stock. Mark Wendt has one and I have the other. (Don Schneider)
And if anyone would like to borrow the tool Don made up for me, we can do the same thing Don and Todd set up for the planing form tools. You use the tool in conjunction with the "Rollies Dad's Method" for truing up the lathe, and it works like a champ. (Mark Wendt)
I appreciate the assistance and the offer. I think I'll have a shot at making one myself though thanks to Don directing me to instructions and a photo on the LMS web site. Seems pretty straight forward to me. Of course, if I mess it up I'll know where to find a few sets. (Wayne Kifer)
Here are two sites to help you align your lathe.
Little Machine Shop Tailstock Adjuster
Gadget Builder Alignment
To take the chuck out of the equation I faced off a morris taper center that fit the head stock. Drilled it for a .5" drill rod. Put a center hole in the bottom of the hole. Turned a point on one end of the rod to match. Drill a center on the other end of the rod. Epoxy together with the morris taper in the head stock and the rod held centered with the tail stock till the epoxy cures. You may want to let the lathe turn slowly while the epoxy cures. It won't come out exactly straight but close. Make the rod as long as you can.
I didn't bore out the head stock. Mine was large enough to pass a .75" rod to start with. (Don Schneider)

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