Chatter free cutting

[bluehawk]

Hi all
When turning 1020 mild steel on the lathe I allway get tool chatter when using a round button tip
to machine a radius Iv tried diff speeds and feeds and diff cutting compounds but not much improvement
Iv put up with this for years and now Im throwing it out there any ideas (cutter is set on center )
Bill N

 

[bluehawk]

Thanks Paddy
I will try those techniques and let you know how it goes I wounder if running the tip a little under center
would help as well any way Ill get back to you after further trials
Regards Bill N

 

[irishwoodsman]

just a thought did you put a indicator on your chuck just to make sure it was true, i had the same prob with my sheldon when i first got her and it turned out to be out of wack had to buy a new backing plate. just a thought:thinking:

 

[Tony Wells]

Below center will aggravate the chatter. A little high if anything would worth a try. Paddy has it right, get in; get out, no dwell. And actually a dull tool, which requires a little more pressure to get into the cut won't generally chatter as bad as a new, sharp tool.

 

[goldenchips2]

smaller radius inserts to begin with.
Slow down the spindle speed and go with a heavier cut.

 

[bluehawk]

thanks goldenchips2 yep that prity much sums it up ,depending on what your cutting and the dia
every ones advice has been helpful ,like every thing it pays to play with diff cutters,feeds and speeds
thanks Bill

 

[Kevin45]

When you get to the corner that you want the radius in, try slowing your speed down to the point that it is almost scraping the metal off instead of cutting it. Also try a little oil on your piece. Unfortunately the larger the radius the greater the chance for chatter. Not to many ways around it unless you have a CNC turning center where you can keep constant motion on your toolbit.

 

[bluehawk]

Hi Kevin45 Im working on fitting a speed controler to my lathe and then will be able to try diff slow
speeds even try to tune the speed to the feed on the fly (as I cut ) any way many thanks for the tip
Bill

 

[Tom Griffin]

Bill,

I suspect the chatter problem lies with your tool holder. The one in your pic looks very light for an insert with that much contact area. Try finding a holder with more beef to it. I think whats happening is the holder is flexing side to side, causing your chatter. Also, try to reduce the amount of overhang from your tool post as much as possible.

Tom

 

[bluehawk]

Tom you are spot on the tip holder is a bit on the light side and min over hang is a must but I think my other problem
is that the sadle and top slide on my lathe is a bit on the narrow side and does not resist flexing very well Iv noticed it
jumping a little on intermitent cuttig but Im trying to work with this and use the best pos technique to get the best result
regards Bill