[murphdog]

Looking at adding a VF2SS to the shop and somewhat concerned about rpm's.
Is anyone using balanced toolholders on 10 & 12K spindles. We currently only have 7.5K spindles.
This will be an aluminum only machine and we could use the higher rpm's on several tools we use.
Thanks
Murphdog

[Geof]

Balanced toolholders are needed for 10,000 rpm and above. At 10,000 rpm you can get away with some imbalance; you will hear a droning sound running a poorly balanced tool at this speed: But you will (probably) not damage anything even if you ignore the drone and keep running that holder. At 12,000 rpm you run a risk of toasting your spindle bearing if you run an unbalanced holder.

[Vulin]

We recently picked up a VF2-SS, before we only had 7.5k spindles. I have throwin in one of our non balanced tool holders and run it at 10 and 12k and can immediately hear the difference. We picked up some Techniks tool holders which are balanced, I was unable to convince them to go shrink fit. Quite a difference! Anything over 7.5k I would run balanced.

[murphdog]

Hello Vulin,
So you are just using "balanced" toolholders or did you look into buying a balancer?
Thanks

[WallyL7]

I just buy all balanced holders...have never actually tried to balance them myself.

[Pondo]

Some rules of thumb I used in the shops I have run:
No set screw type toolholders over 7500 RPM (I personally don't use them over 5K)
No TG type collet holders over 10K
Shrink fit holders only over 15K
Any tools 1/2" or over must be indicated in and running within .001 TIR over 10K

Listen to the tools run - it's pretty obvious when something's out of balance.

[Pondo]

And don't buy cheap-ass toolholders - they are never worth the $ savings.

[murphdog]

And I assume that when you are not within .001 TIR do you just rotate/change collets or change holders until you get there????
Thanks

[Geof]

Nah just bash it with a big hammer. :-)

[Pondo]

No hammers

The indicating is more of a check to make sure it's all set up right.
No chips or grit, no cracked holders, no damaged tools, no crap in the spindle, etc.