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- Sep 8, 2019
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I won't be able to fix this anytime soon. I am leaving home for 8 weeks. I will have plenty of time to study up on the matter, and really take care of it when I get back home.
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Is 4.6 tenths per inch too much taper for a lathe?
- Thread starter erikmannie
- Start date
- Joined
- Sep 8, 2019
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Recently, I tightened up the gibs on my compound. They were pretty loose. Since then, I have not had any issues with this taper. My compound is at 30 degrees, by the way.
I will be finding out right now if this fixed the problem. As I said before, I won't be able to follow up on the great advice above until May.
Having the compound gibs adjusted makes for more enjoyable machining.
I will be finding out right now if this fixed the problem. As I said before, I won't be able to follow up on the great advice above until May.
Having the compound gibs adjusted makes for more enjoyable machining.
- Joined
- Sep 8, 2019
- Messages
- 4,392
It would appear that I fixed this problem by tightening the gibs on the compound.
Boy, it sure is nice turning a workpiece and having the diameters more or less the same all the way down the turned piece!
Boy, it sure is nice turning a workpiece and having the diameters more or less the same all the way down the turned piece!
Try the simple stuff first!
I'm not a huge fan of the RDM because it strikes me as trying to correct one problem by introducing another. That might not be true for lightweight lathe that flex a lot when installed, but on a reasonably rigid lathe, I think you're better off to actually make sure that the headstock is properly aligned, and then move on to check the tailstock.
Harold Hall outlines a method for doing this in his book _Lathe Work, A Complete Course_. You chuck up a piece of heavy bar stock without tail support, no more than 4-5 diameter stick out, turn a cylinder, and then measure it for taper. If it's too far out, you then start adjusting the headstock to get rid of the taper. when the taper is gone, you can finish up the base and then part it off and have a nice little cylindrical square for your trouble.
Moving on to the tailstock, then you're talking about turning a bar between centers, again looking for taper. You can either use the two collar method or a sufficiently heavy bar that flexing is not an issue. I think I worked out that I would need a 2.5" diameter bar or thereabouts to avoid flexing in my machine. if you get a barrel shape when you measure the bar, then it's flexing in the middle and you need to make lighter cuts, or go to the two collar method.
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I'm not a huge fan of the RDM because it strikes me as trying to correct one problem by introducing another. That might not be true for lightweight lathe that flex a lot when installed, but on a reasonably rigid lathe, I think you're better off to actually make sure that the headstock is properly aligned, and then move on to check the tailstock.
Harold Hall outlines a method for doing this in his book _Lathe Work, A Complete Course_. You chuck up a piece of heavy bar stock without tail support, no more than 4-5 diameter stick out, turn a cylinder, and then measure it for taper. If it's too far out, you then start adjusting the headstock to get rid of the taper. when the taper is gone, you can finish up the base and then part it off and have a nice little cylindrical square for your trouble.
Moving on to the tailstock, then you're talking about turning a bar between centers, again looking for taper. You can either use the two collar method or a sufficiently heavy bar that flexing is not an issue. I think I worked out that I would need a 2.5" diameter bar or thereabouts to avoid flexing in my machine. if you get a barrel shape when you measure the bar, then it's flexing in the middle and you need to make lighter cuts, or go to the two collar method.
Sent from my Pixel XL using Tapatalk