This can increase rigidity but at the same time help in keeping the tool holder from wedge locking inside the spindle taper. By using BIG-PLUS, this type of tooling gives you both taper and end face contact. If the machine has a BIG-PLUS style spindle it is a good idea to use BIG-PLUS holders especially if the holder is going to be in the spindle for a long period of time, the spindle speed is high and if a lot of side load will be applied to the cutter. By using 85%, this keeps the holder rigidity but also keeps the contact to a level that helps release the tool. If there is close to 100% contact see Okuma Service. Unclamp the holder and check the contact of the two tapers. Using a high-quality holder, apply blueing to the taper of the holder and clamp the holder into the spindle. It is also a good idea to check the taper contact of the spindle taper. Perform visual spindle taper and contact checks.
High pull force on the tool holder can cause the knock out cylinder to have to work harder to overcome the excessive force on the drawbar before striking the end of the pull stud to break the two tapers loose. If the pull force is over the high limit, it might be a good idea to have someone from Service come in and take a look. Wipe the tool holder taper down before inserting it back into the spindle.Ĭheck the pull force of the spindle. When possible and an opportunity arises, remove the tool from the spindle and wipe the taper of the spindle out with a clean cloth. If the machine is going to be down for an extended amount of time or overnight it is a good idea to remove the tool from the spindle then clamping the spindle before shutting the machine down.
This phenomenon happens when the taper of the tool holder wedges into the spindle taper and the unclamp cylinder device cannot knock the two tapers apart. Occasionally during the machining process on machining centers, some tool holders may become stuck inside the spindle taper after the machining process for that tool is completed.