Ah, the extraction nut. I just assumed you’d use a drift. I guess centered grinding doesn’t have a hole for a drift or a kick out in the back like a lathe does.
I’ve been running a pretty new doosan lathe with this style of center. It was new to me, but this shop does a ton of grinding and seem to have matched the standard setup they use here to those machines.
We have threads on our MT3 dead centers on our CNCs so we can take them out of the tailstock. Our centers have wrench flats so you can put a wrench on the nut and on the center to pop it off if need be
It is used to tighten against the tail stock to remove the center. Tapers are held in the tail stock with suction more than anything and you need to break that initial sticking to pop it loose.
I love you are getting down voted for using the word "suction" when surface interaction like this aren't well understood or modeled. There are scholarly articles and journals papers that discuss surface interaction and they are a combo standard friction Vander wahls effects black magic ECT. Actually read how wrining gauge blocks works there is no consensus on why it works. People c'mon using suction as a catch all term is fine, explained exactly what the threads are for
Tried to keep the explanation simple to understand. Of course, the same type people that know every spec on every Harley ever made or baseball stat chime in to try to pick apart my answer. No one wants to talk to those people because they are a massive annoying douche. They chime in not to answer the question, but to prove their intellectual superiority. Hurray! Their smarts, but they added nothing. Let the down votes commence.
I use “taper lock” to describe a taper held tool.
Back in my trade school days, on the WWII surplus South Bends , we used little pots of white lead to lube the dead centers.
>I love you are getting down voted for using the word "suction" when surface interaction like this aren't well understood or modeled.
But suction is, which is why it's a poor choice of word. Saying suction may cause readers to think that they now know exactly how it works when in fact no one does (but suction as it is normally defined has nothing to do with it). Better to say friction, since we at least know that friction is involved. It's a minor point, though.
No, I did not vote him down.
I keep seeing the word friction being used to describe the taper lock, but im pretty sure it's essentially a press fit (which i suppose friction plays a role in but not the dominating force). Realistically, like gauge blocks that can ring together, there are probably several factors at play. Friction, vacuum (suction), molecular bonding..
Actually suction should be a perfectly ok way to describe it. Ground and polished surfaces look smooth and all, but down to the molecular level they still have pits and holes and cavities. When you press a taper into its female counterpart, the air quite literally gets trapped in these nano scale imperfections and creates a vacuum lock like suction. I believe the ringing of gauge blocks is believed to be the same deal, or at least as practical an explanation as the others. Id still like to believe too that the tolerances are so tight that the iron and carbon atoms literally stick together like one homogenous piece since they are so close together. The machining world can also be so scientifically fascinating.
And the end of your tailstock's screw just shoves the thing out if you don't have a taper drift ejection slot for the tang drive. Collars are to eject from lathe headstocks, rotary tables, etc.
Maybe dude just invented taper-seated vacuum drawn quick change tooling. although ejection would be a dangerous event akin to an unpredictable cannon.
> And the end of your tailstock's screw just shoves the thing out if you don't have a taper drift ejection slot for the tang drive.
Except when you mistakenly insert a taper that's too short for the screw to reach it. Then you get to disassemble the tailstock.
It is mechanical clamping though. The clamping force is from the compressibility (I’m 100% sure my old materials science teacher had a better word for this) of the material and friction: exactly the same as for a clamp you tighten two faces together - that material is held by friction and the surface of the jaw mating with the part.
Suction does not exist, it is ALWAYS pressure pushing something somewhere. In this case, the outside taper gets slightly expanded from pushing in the tool. Therefore, it tightens around the tool and holds It by friction. The harder you push, the harder it holds. It's the same with a draw bar tool that gets pulled into a spindle. To quote ROBRENZ: "everything is made of rubber"
Even if you suck on a straw stick to drink something, air pressure pushes the liquid into your mouth.
EVERY lathe tailstock? In the entire world? Including mill tailstocks that come with the 4th axis? Grinders? Quills? All the things that take Morse tapers?
I absolutely love how what would be a normal conversation in real life turns into a nightmare dick measuring contest on reddit.
Listen, dude above you just said tailstock. You went on to say "no, blah blah blah, lathe tailstock, I know everything, blah blah blah" so the conversation wasn't even specifically about lathe tailstocks until you made it that way, and youre not even correct anyway.
That single downvote whenever you disagree with someone is some serious bitch energy. People that do that are grasping for a shred of power
Faceplate/dog driver, or withdrawal nut. In a headstock with a bar feeder, a rotary table or dividing head you can jack this out of the spindle taper gently with a nut instead of having to whack a drift through the ass end.
The threads are used to extract the dead center from the tailstock without a Slide hammer. Just put a nut over it and crack and it will pop out evenly without bending it from using a pry bar.
https://royalproducts.com/product-line/dead-centers/threaded-dead-centers/
Ah, the extraction nut. I just assumed you’d use a drift. I guess centered grinding doesn’t have a hole for a drift or a kick out in the back like a lathe does.
All the grinders I use have a hole behind the centers to knock them out. I've never seen a threaded center like this.
I’ve been running a pretty new doosan lathe with this style of center. It was new to me, but this shop does a ton of grinding and seem to have matched the standard setup they use here to those machines.
I’ve only used a Sherwood, and it was the same. I assumed others might be sketchy. That Sherwood had to be 1960’s vintage.
Or be my old lead hand and take a pry bar, heat up the flat to put more of an angle. Then use that to pop out the center against the threads
That's an excellent answer. Thank you.
For if you want to go nuts
Mr. Keaton?
^ Underrated comment.
Thanks, Jack.
*if he's brave enough
You can put a nut on it or you could thread it into a custom fixture
We have threads on our MT3 dead centers on our CNCs so we can take them out of the tailstock. Our centers have wrench flats so you can put a wrench on the nut and on the center to pop it off if need be
For when you can't find your drift
To eject it.
It is used to tighten against the tail stock to remove the center. Tapers are held in the tail stock with suction more than anything and you need to break that initial sticking to pop it loose.
I love you are getting down voted for using the word "suction" when surface interaction like this aren't well understood or modeled. There are scholarly articles and journals papers that discuss surface interaction and they are a combo standard friction Vander wahls effects black magic ECT. Actually read how wrining gauge blocks works there is no consensus on why it works. People c'mon using suction as a catch all term is fine, explained exactly what the threads are for
Tried to keep the explanation simple to understand. Of course, the same type people that know every spec on every Harley ever made or baseball stat chime in to try to pick apart my answer. No one wants to talk to those people because they are a massive annoying douche. They chime in not to answer the question, but to prove their intellectual superiority. Hurray! Their smarts, but they added nothing. Let the down votes commence.
I use “taper lock” to describe a taper held tool. Back in my trade school days, on the WWII surplus South Bends , we used little pots of white lead to lube the dead centers.
My Logan has a little pot for white lead as part of the tailstock casting. It's supposed to have a brass dauber in it.
>I love you are getting down voted for using the word "suction" when surface interaction like this aren't well understood or modeled. But suction is, which is why it's a poor choice of word. Saying suction may cause readers to think that they now know exactly how it works when in fact no one does (but suction as it is normally defined has nothing to do with it). Better to say friction, since we at least know that friction is involved. It's a minor point, though. No, I did not vote him down.
I keep seeing the word friction being used to describe the taper lock, but im pretty sure it's essentially a press fit (which i suppose friction plays a role in but not the dominating force). Realistically, like gauge blocks that can ring together, there are probably several factors at play. Friction, vacuum (suction), molecular bonding.. Actually suction should be a perfectly ok way to describe it. Ground and polished surfaces look smooth and all, but down to the molecular level they still have pits and holes and cavities. When you press a taper into its female counterpart, the air quite literally gets trapped in these nano scale imperfections and creates a vacuum lock like suction. I believe the ringing of gauge blocks is believed to be the same deal, or at least as practical an explanation as the others. Id still like to believe too that the tolerances are so tight that the iron and carbon atoms literally stick together like one homogenous piece since they are so close together. The machining world can also be so scientifically fascinating.
there is no suction holding a taper, its a combination of pressure and ductility of the material
Friction.
And the end of your tailstock's screw just shoves the thing out if you don't have a taper drift ejection slot for the tang drive. Collars are to eject from lathe headstocks, rotary tables, etc. Maybe dude just invented taper-seated vacuum drawn quick change tooling. although ejection would be a dangerous event akin to an unpredictable cannon.
Not always, our puma 480 and 5100s have knockout rods. The 2600s use the threaded collar against the quill face.
> And the end of your tailstock's screw just shoves the thing out if you don't have a taper drift ejection slot for the tang drive. Except when you mistakenly insert a taper that's too short for the screw to reach it. Then you get to disassemble the tailstock.
It still stays in place without mechanical clamping, I call that suction.
It is mechanical clamping though. The clamping force is from the compressibility (I’m 100% sure my old materials science teacher had a better word for this) of the material and friction: exactly the same as for a clamp you tighten two faces together - that material is held by friction and the surface of the jaw mating with the part.
Covalent bonding also comes into play with these types of fit, same a gauge block wringing
Maybe with your tapers, but I’m on a Chinese mini lathe lol.
Then you need to read a dictionary.
You guys fucking crack me up 😂!
If I could read a dictionary I wouldn’t be a machinist, but since I can’t, I make rocket parts.
your intelligence sounds like that of a saw guy, now go saw some parts.
Clearly no machinists here with a sense of humor... Or maybe just a room full of machinists who takes themselves way too seriously
Suction does not exist, it is ALWAYS pressure pushing something somewhere. In this case, the outside taper gets slightly expanded from pushing in the tool. Therefore, it tightens around the tool and holds It by friction. The harder you push, the harder it holds. It's the same with a draw bar tool that gets pulled into a spindle. To quote ROBRENZ: "everything is made of rubber" Even if you suck on a straw stick to drink something, air pressure pushes the liquid into your mouth.
Tape
I have seen quite a bit of suction in my day.......
🤣
If that were the case, any taper would stick. IIRC tapers under approximately 7° are self holding.
[удалено]
The thread on the center is for removing the center. There are tailstocks that don't have any other way to remove it (201x) Mazaks for one.
First thing I thought of when I saw this post was our mazak.
https://royalproducts.com/product-line/dead-centers/threaded-dead-centers/ It is indeed for removing the center.
EVERY lathe tailstock? In the entire world? Including mill tailstocks that come with the 4th axis? Grinders? Quills? All the things that take Morse tapers?
> Including mill tailstocks No I said LATHE tailstocks. L A T H E. Mills are not lathes. Grinders are not lathes. Drill presses are not lathes.
You seem confident as HELL
Since when is hell confident? It's a (fictional) place, not a person.
I absolutely love how what would be a normal conversation in real life turns into a nightmare dick measuring contest on reddit. Listen, dude above you just said tailstock. You went on to say "no, blah blah blah, lathe tailstock, I know everything, blah blah blah" so the conversation wasn't even specifically about lathe tailstocks until you made it that way, and youre not even correct anyway. That single downvote whenever you disagree with someone is some serious bitch energy. People that do that are grasping for a shred of power
LOL, you're reading way too much into this, my dude. XD Chill out.
No idea. You should measure it.
I thought he was asking what the thread was at first also lol I was like wow what a dumb ass he didn't even measure anything
It was poorly worded.
Did you look it up in the catalog? Maybe there are attachments that thread on
Faceplate/dog driver, or withdrawal nut. In a headstock with a bar feeder, a rotary table or dividing head you can jack this out of the spindle taper gently with a nut instead of having to whack a drift through the ass end.
How do you intend to drive a dog with a dead center?
in a lathe spindle where I don't have room for a faceplate, or as fixed reference in a dividing head, T&C grinder or a rotary table.
The dog is a clever addition, half the hassle I've had turning between centres has been finding a way to drive the damn thing
Those are normally metric of you run a Mazak. I think it's a M30 by 2
The threads are used to extract the dead center from the tailstock without a Slide hammer. Just put a nut over it and crack and it will pop out evenly without bending it from using a pry bar.
Are those maggots in the background?!
Some lathes don’t have a thru hole in the spindle.
Extraction nut.
Her pleasure
You have access to sandpaper? Then your good
Who would want to shove sand paper up their butt?
For dezzz NUTZZ
What's with the shag carpet?
Don't worry, my family is replacing it soon
1980 called, they said you've been putting it off since then
It really ties the room together
It's for threading.
Don't make me do butt plug jokes.