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- Apr 1, 2013
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No expert here but wouldn't reversing the two side jaws have given better support?
Mark
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Chucking Up Perpendicular Round Stock? (lathe)
- Thread starter Argonavis
- Start date
No expert here but wouldn't reversing the two side jaws have given better support?
Mark
Thanks to everyone for your thoughtful replies and comments!
First, let me thank you for having taken the time for such a thorough reply, as well as the drawings! In answer to your question, I'm often intrigued by the notion that the lathe is the only tool that can build itself. Hence I often wonder about how certain operations might be accomplished without the use of some of the tools we are fortunate to have access to. In this case, I don't have a readily-available fixture to hold the stock in the tailstock -- but I do have a 4-jaw chuck. So the question then becomes one of work-holding and indicating. This is what started me down this path. However, perhaps it might not be a bad idea to invest in some new tooling (actually, when is that ever a bad idea?).
In addition to using a V-grove fixture of some sort to center the work, it dawned on me that this might be a useful application of a Starrett no. 65 "center tester". Placing the center punch would be a challenge, but then this device would guide the adjustment of that point onto the axis of rotation.
Thanks again for all the ideas!
First, let me thank you for having taken the time for such a thorough reply, as well as the drawings! In answer to your question, I'm often intrigued by the notion that the lathe is the only tool that can build itself. Hence I often wonder about how certain operations might be accomplished without the use of some of the tools we are fortunate to have access to. In this case, I don't have a readily-available fixture to hold the stock in the tailstock -- but I do have a 4-jaw chuck. So the question then becomes one of work-holding and indicating. This is what started me down this path. However, perhaps it might not be a bad idea to invest in some new tooling (actually, when is that ever a bad idea?).
In addition to using a V-grove fixture of some sort to center the work, it dawned on me that this might be a useful application of a Starrett no. 65 "center tester". Placing the center punch would be a challenge, but then this device would guide the adjustment of that point onto the axis of rotation.
Thanks again for all the ideas!
- Joined
- Sep 29, 2014
- Messages
- 2,102
Nothing like practical experience when dialing in parts and making do with what you have.
On Monday I have to finish turn a shaft with eccentric diameters, I finish turned the concentric diameters yesterday from HRS 1045 bar. One of the mill guys center drilled the offsets in a Bridgeport EZ-Trak knee mill with a right angle attachment today. I will put one end in a 4 jaw and offset it ,375" and the other end on a live center, flip it and turn the other end.
A bit of indicator work involved (-:
Rough sketch of part, not to scale of course.
Yes it would have held it tighter but I was being lazy. It was being supported by the two sides but not held. It was a light cut so it wasn't really needed. I even said to hold it on the sides in the earlier post but it was the only picture on my phone that showed what I was trying to describe. Guess its do what I say not what I do.