Big-Plus Big-Plus

toolHoldersQ. Can existing machines and tool holders be used?

A. Yes, existing machines and tool holders with BIG-PLUS spindles and tool holders. When a new machine with the BIG-PLUS spindle system is introduced, conventional tool holders can still be used as well as BIG-PLUS tool holders. It is not necessary to purchase only BIG-PLUS tool holders.


kaiserQ. Are new accessories required?

A. No, they are not required. BIG-PLUS spindle system uses existing accessories such as a tool presetter and tool holder tightening fixture because it has the same dimensions as a conventional steep taper shank. Therefore, no extra cost is needed.


kaiserQ. Is there any effect on the life of a machine spindle and tool holder?

A. Simultaneous fit of taper and face will prevent vibration due to heavy or high speed cutting and reduces fretting corrosion on taper. This will increase the life of both spindle and tool holder.


kaiserQ. What benefit can be expected at high spindle speeds?

A. At high spindle speed rotation, a machine spindle will expand outward due to centrifugal force and heat. Due to this effect, a conventional tool holder without simultaneous fit will be pulled into the spindle and may even become locked in place when the spindle stops. However, with face and taper contact of BIG-PLUS, the tool holder cannot be drawn into the spindle even at high speed rotation as the flange face contacts the spindle nose. This will also eliminate variation of Z-axis projection length due to high speed and heat.


kaiserQ. What effect will there be on machining results?

A. Rigidity is enhanced by simultaneous fit of taper and face. There are tremendous productivity improvements with heavy or high speed cutting, deep or large diameter boring, and especially when using a cutting tool with longer projection length. Another important improvement is the tool life of endmilling operations due to the vibration free cutting.


Q. What influence is there on ATC (Automatic Tool Change) repeatability?

A.Because a BIG-PLUS tool holder is rigidly held against the taper and a flange face, the influence of side loads due to retention knob clamping systems is minimized. This reduces the error of runout due to automatic tool change and improves the precision of finish boring operations.


Q. Is there any problem using BIG-PLUS tool holders on different BIG-PLUS machines?

A.No, there is no problem. BIG-PLUS spindle system has strictly controlled dimensions and tolerances of the machine spindle and tool holder. In order to guarantee simultaneous fit between taper and face, the tolerances are measured by each machine tool builder by using an exclusive set of high accuracy gauges and measuring devices. Full interchangeability exists between all BIG-PLUS machine spindles and BIG-PLUS tool holders.

Strict gauge controls for BIG-PLUS spindles are maintained by the licensed Machine Builders.