Tail stock tightening question

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Takari

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Feb 18, 2016
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16
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Portland
I purchased a G0752 Grizzly metal lathe and have a neurotic newbie question: Should I expect the tailstock lock nut to lock down in the same rotational position no matter where the tailstock is on the bed way?

With the tailstock sitting at the far right end of the bed, I loosen the nut to slide the tailstock left. As I slide it left toward the spindle I have to loosen the nut even more or it binds. It's takes another 1/2 turn to get it to the spindle end.

When drilling plastic I use a lot of quick tightening and loosening of the tailstock so it's a pain to have it tighten at different rotations vs positions.

My old mini-lathe was better. I know the underside of the bed is not precision ground so maybe I just got lucky and I'm spoiled.

Thanks for any feedback!
 
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epigolucky

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Jan 3, 2014
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I don't have a Grizzly lathe, but my tailstock does not lock down in the same location after it is moved or adjusted either. If I keep it in the same place and unlock and relock, it will lock down in approximately the same position.
 

Ed McDonnell

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Oct 20, 2008
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Melbourne, FL
My lathes (powermatic and jet wood lathes, cheap chinese metal lathe) lock down in the same position across the length of the lathe bed. A difference in locking would imply a difference in thickness of the ways (and it would drive me nuts). It looks like the locking nut on your lathe is M12x1.75. If I did the math right, a half turn would be equal to about 1/32" difference.

Have you measured the thickness of the ways at both ends (both sides)? Do the bottom of the ways feel smooth with no crud that might interfere with locking? Have you checked the locking plate on the bottom of the tailstock to see if it can be oriented differently? Orientation of the locking plate might make a difference in locking.

You could always call grizzly tech support and see what they say. I would expect better in my lathe, but maybe $1,700 doesn't buy better these days.

You could always look into converting your tailstock to lever operation which might be less frustrating than a wrench.

Good luck.

Ed
 

Takari

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Joined
Feb 18, 2016
Messages
16
Location
Portland
It looks like the locking nut on your lathe is M12x1.75. If I did the math right, a half turn would be equal to about 1/32" difference.

Ed

Ed, You did the math right! There is a 0.035" difference from the far right to the far left. It's a progressive taper.

The rest of the machining looks great. The carriage and cross slide are both very smooth with zero play.

Now to decide if I live with it or not. FWIW, this is exactly why I'm attracted to making kitless pens. It's a product made with precision and care.
 

More4dan

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Mar 17, 2016
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2,102
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Katy, TX
My lathes (powermatic and jet wood lathes, cheap chinese metal lathe) lock down in the same position across the length of the lathe bed. A difference in locking would imply a difference in thickness of the ways (and it would drive me nuts). It looks like the locking nut on your lathe is M12x1.75. If I did the math right, a half turn would be equal to about 1/32" difference.

Have you measured the thickness of the ways at both ends (both sides)? Do the bottom of the ways feel smooth with no crud that might interfere with locking? Have you checked the locking plate on the bottom of the tailstock to see if it can be oriented differently? Orientation of the locking plate might make a difference in locking.

You could always call grizzly tech support and see what they say. I would expect better in my lathe, but maybe $1,700 doesn't buy better these days.

You could always look into converting your tailstock to lever operation which might be less frustrating than a wrench.

Good luck.

Ed

A cammed lever conversion might be worse. Unable to get it to lock at all in places.

Mine gets a little tighter at the opposite end of the bed away from the head where the serial number is etched. It has saved me sliding the tale stock off a few times though. Would a ratchet wrench fit? 2 tugs would be easy if didn't have to reposition it.
 

Takari

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Joined
Feb 18, 2016
Messages
16
Location
Portland
A cammed lever conversion might be worse. Unable to get it to lock at all in places.

Mine gets a little tighter at the opposite end of the bed away from the head where the serial number is etched. It has saved me sliding the tale stock off a few times though. Would a ratchet wrench fit? 2 tugs would be easy if didn't have to reposition it.

Good to know that others have some variation too. I called Grizzly and also had my machinist apprentice son (who's responsible for my new found hobby) look into it. Long story short I ended up checking the upper bed way to make sure it wasn't the problem. It is a few thousands over the entire length of the bed so I'm going to call it good.

I use a little home made contraption to lock and release the tailstock to I can move it out of the work quickly. I'm able to get it to tighten down over most of the bed if I put it on just the right place on the nut.

Back to making pens now. : ) Thanks!!
 

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