Hey Kurt,
What a good idea about extending the boring bar! Will that make the bar flex too much?
About how much should I set the apron over? I think that this is about how this will go.
1. I'll lay out the center on each end of the 2" round stock that I bought. Then I'll center drill the ends.
2. I'll mount the round stock between centers, and use a lathe dog and driving plate to rotate the work and turn it down to 1.750" diameter.
3. I can use a parting tool in my Aloris tool post and partially part off a section 3.025" long. This will give me a little material to remove while cleaning up the parted end. I think that I will remove the work and finish parting it off using a hack saw and a bench vise.
4. I'll remount the 3" piece on the lathe using a four jaw chuck, and indicate it true using a dial indicator.
5. I'll face the parted end to clean it up and make the work 3" long. Then I'll center drill this end.
6. Next I'll mount a Jacobs drill chuck in the tail stock and through drill the work with the biggest drill that I can find in my shop. (I think that will only be 1/2" = 0.500".)
7. I remember from my machine shop class that I can extend the work piece no further than 2 times the diameter from the chuck and maintain a good rigid set up. In this case I will only have about two inches out beyond the jaws of the chuck.
8. I think that I should do my taper set up at this point.
9. I think that I will order a boring bar from one of the supply places, as the one that I have will never even start in a 1/2" hole.
10. I think that I will have to move the compound slide as far back as I can. I think that I have to move the carrage very close to the work and move the cross slide feed in toward the center of the lathe and start the boring bar in the center of the tail stock end of the through hole in the work. Then I think that I need to back the cross slide towards me until the boring bar just touches down on the inside end of the through hole.
11. Next, I think that I will need to back the carrage away from the work, zero the feed wheel dial of the cross slide and tighten up the carrage lock nut.
My old shop manual says that I should take a light cut, back the cutter out, measure the results, then calculate how much more material needs to be removed. Then remove all but 0.002" to 0.005" in one or two roughing cut passes. Finally cleaning up the last 0.002" to 0.005" in a finish pass.
I think that my lathe is so old and ricketty, and that the boring bar that I will have to buy is so light; I'll have to take four or five light cuts by backing the cross slide back toward me, then running the compound side forward to go from 0.500" to 0.7867" or the largest whole diameter on the tail stock end of the work.
12. I think that a step will form inside of the work because my compound slide will only travel so far forward. I think that once the tail stock end of the work measures about 0.786", I will have to center the boring bar in the hole, back the boring bar out using the compound slide feed wheel, loosen the carrage clamp nut and move the saddle toward the head stock until the boring bar nose is in the 0.500" through hole. Then repeat steps 10 and 11 until I can see that the this second part of the taper meets the first part of the taper that I will turn.
13. Next, I think that I should clean up any rough tool marks inside of the work with a bit of emory cloth, and get that last 0.0007" on the tail stock end hole.
Well that is how I think that it should go! Yes? No? Maybe so!
Hey rws,
The expoxy thing is starting to look mighty good, but I still want to do this the hard way just for the heck of it!
Regards,
Virginia Jake