Sherline Tailstock Misaligment

I've taken a few basic measurements on the near (operator) side and the far side of the tailstock base. There is some stock to work with, but any modifications to the far side of the base would have to be carefully thought out. I don't know much about the strength of materials, nor the forces that would be applied when dealing with clamping something where angular pressure would be seen. It may be possible to predict those forces with finite element analysis software. It's easy to see that a small radius (around .020) would be needed in the corner if one were to mill the base of the tailstock to accept a modified gib. A sharp corner would create a stress riser in a location where the material would end up being the thinnest. I'll try to come up with a sketch showing dimensions, and let others here on the forum comment on the value and practicality of what I've come up with.
 
blu73 said:
... I don't know much about the strength of materials, nor the forces that would be applied when dealing with clamping something where angular pressure would be seen. It may be possible to predict those forces with finite element analysis software.
Click to expand...
I have an idea for an approach: Confirm through beam-deflection equations that a modified tailstock base deflects much less than the neck of the Morse taper to force applied along the x-axis to a tool installed in the tailstock .

I imagine that the neck of the Morse taper on a tool installed in the tailstock is the weakest point.

I have a book that contains equations on the defections of beams: Mechanics of Materials, 2nd edition, by Gere and Timoshenko (1984). It was the textbook in a civil engineering course that I took 30+ years ago.
 
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Karl A,
I hadn't thought of measuring the deflection of the tailstock spindle. My main concern was the strength of the thinnest part of the base if it is milled to accept a gib. The quick measurements I took seem to show the amount of material left would be somewhat lacking in cross section. The area that troubles me most would be at the inside corner left by a milling operation. Even with a .020 radius in there, it could be the one place that would be most likely to fail.
 
I came across a blog post by Tom Carbone describing a modification to the Sherline lathe tailstock to make it adjustable:
Shereline Lathe - Adjustable Tailstock

The blog post also includes a photo of the adjustable tailstock that A2Z CNC sold. I had only read about it; I had not idea what it looked like. I read somewhere that A2Z incorporated Sherline's mill accessory the Adjustable Right Angle Tailstock.

Here are photos from the blog post.
1632279419249.png1632279453100.png1632279476455.png

Karl
 
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