TBC live center still getting hot

[Woodchipper]

Been working on a pen blank but watching the live center. I have reviewed other responses in another thread but nothing seems to work. I screw the quill down and check the blank. It turns but screwing it down an itty bitty turn keeps the blank from turning but the LS still gets hot. I put a drop of lubricant in the back of the TS...didn't work. Defective? Not packed with grease or lube properly? Help as I have several pens to turn or go back to the long mandrel for two blanks. BTW, this is still the first of two blanks for a pen kit. Many thanks for reading this and your replies.

 

[1080Wayne]

Live center bearings can fail from excessive thrust over time . Can you define `itty bitty turn ` in degrees of arc ? For me , I would probably be in the 10-15 degree range for a pen , and 15 - 20 for a S&P shaker . You may have very strong hands . If friends sometimes react with a bit of a grimace when you shake their hand , you would be in that category .

 

[Woodchipper]

This is new and the second time it has been used. I have only turned one blank; I went back to the long shaft mandrel to finish the other blank, apply MM and polish both blanks. As for arc, I'll have to go into the shop and guesstimate with a gauge- Arc seems to be not more than 15 degrees, more likely 10 degrees. Experimenting with the quill, anything less, the blank spins when the gouge is applied. I advance the quill until the blank no longer spins. Strong hands? No. At my age, I'm conscious of what others can experience. There is a good mechanical advantage for the quill; not much needed to crunch the mandrel. I have had a Harbor Freight 60 degree live center for years and it has never heated up. Checked it today when I I turned the second blank and polished it. Have had the lathe for over 15 years, still going like the pink bunny!
I'm of the idea of giving it to my son and have his guys in the machine shop look at it. Even disassemble it if needed to inspect the innards for lubrication. FWIW, heard of cars coming off the assembly line, started up and......someone forgot to put oil in the engine or the oil plug was left out!

 

[d_bondi]

Control Experiment idea....

Put something soft and grippy in the chuck, bring the live center up against it just enough to make sure that there is enough friction to cause the live center to turn. Turn the lathe on to high speed and let it run for a while.

Does the live center get hot?

If not, then the next step is to try to simulate more pressure, either directly in on the live center, or parallel to the axis of rotation, simulating the pressure of the turning tool or sandpaper.

I have 4 live centers, the one that came with my Jet lathe, a nice Record Power, a cheap mandrel saver live center from Amazon, and an inexpensive 60 degree from Amazon. I have never noticed any of them getting hot.

Just an idea...

 

[Woodchipper]

d_bondi, worth a try. will let you know what happens.

 

[Woodchipper]

d_bondi, printed your advice but noticed this is not a chuck/live center issue but a turning between centers system so no chuck is involved. But I think I can adapt your ideas to the TBC system. Again, thanks. My HF 60 degree live center works fine.

 

[d_bondi]

d_bondi, printed your advice but noticed this is not a chuck/live center issue but a turning between centers system so no chuck is involved. But I think I can adapt your ideas to the TBC system. Again, thanks. My HF 60 degree live center works fine.

For what I was suggesting, I don't think what is in/on the headstock is what is important. It is only there to turn the live center in the tail stock for you.

Perhaps I am not understanding the issue. When I turn between centers, I use a 60 degree dead center in the headstock and a standard 60 degree live center in my tailstock quill.