Stopping chatter ......

[toolznthings]

Stopping chatter on lathe turnings can be a real problem, especially on long small diameters and even larger turnings. When all else fails with speed, feed, and tool radius the following solution usually works.
I have made several small hand held lead " hammers " about three inches long and one inch plus in diameter. Handy for numerous uses around the shop.



Pictured is how I would use the lead when turning. ( an example ) I would use the smallest tool nose radius practical, carbide or HSS, adjust my RPM and feed and let the lead slug ride on the work piece at the point where the tool is cutting. It is not necessary to apply heavy force as to effect the cutting diameter, but enough contact to absorb the vibrations from the cut. Follow along the cut as needed. A drop of oil also helps.



Doesn't always work, but has saved the day more than once when all else has failed.

 

[Herbiev]

A great tip there. Thanks for sharing.

 

[kiwi2]

If you want a cheap source of lead for this try the local tyre shop. They get only peanuts for their scrap balance weights and I've bought some for only a couple of dollars a kilogram. The steel bits float to the top during melting and are easily picked out.
Regards,
Alan C.

 

[tornitore45]

If you want a cheap source of lead for this try the local tyre shop.

That worked about five years ago, the shop did not even want money, they just say help yourself to the bucket.
More recently that did not work as the wheel balancing weight are now made of some alloy but no Lead.

 

[steamtoys]

Great idea - Fine pictures. Just happen to have e pile of old
lead water pipe removed from old house plumbing. Thank You
Ron

 

[mcostello]

New age tire weights are supposed to be Zinc, useful for casting also!

 

[Engineeringtech]

Pretty clever solution to chattering, although I would want my hand free rather than holding the lead.

 

[toolznthings]

Hi,

I'll admit it can be a chore holding the lead in position, but its usually for a short period of time. Even shorter when it doesn't work !

 

[rake60]

I've used that trick.
Thanks for sharing it here!

I was working the day shift in the CNC department, dreading the day ahead.
The job was a thin wall part where the OD was turned last.
I knew it was going to chatter and ring like a bell.
The third shift man had four of them finished with no chatter at all.

He said, "Just soak a handful of shop rags in coolant and shove them into the
bore before the OD turning cycle.

It worked perfectly!
After 30 years of being a machinist, I'm still learning every day.

Rick

 

[goldstar31]

This 'stuffing of rags' and 'hanging a piece of lead' on the tool tip an d so on is 'harmonics' and if you look at musicians damping the strings on a violin with their fingers or inside a piano with all that felt and so on, you are striking a chord:hDe:

Simple when you stand back and think

regards

Norman