The #2 MT Safe Driver is SPRING LOADED!
What this means is the point has a spring behind it so you will always achieve a positive connection with the piece you are turning. Not only that, you have complete control over the amount of tension in the spring by adjusting the screw in the bottom! The set screw in the side prevents the point from being ejected due to the tension in the spring.
You no longer have to use the Tailstock to adjust the pressure on the work piece. Simply increase / decrease the amount of tension in the spring by tightening / loosening the set screw in the bottom of the driver.
Why Use a Safe Driver?
A spindle held between a spur and live center can be a potentially hazardous situation. When using a gouge or a skew, a work piece held using this method can catch, become dislodged, or cause injury to the turner due to the unforgiving nature of the biting teeth of a spur. A Safe Driver can help to avoid these potentially dangerous situations. Using a Safe Driver encourages good tool control when training because a catch or heavy handedness merely safely stops the piece being turned. When turning large and heavy spindle type components, make sure you increase the amount of tension in the spring.
Safe Drivers are mounted in the headstock of machines, with a Live Center in the tailstock. Pressure between the headstock and tailstock allow the wood to turn. Because there are no aggressive teeth on the Safe Driver (as there are on Spur Drivers), if the turner gets a catch while working, the wood merely stops spinning while the Safe Driver keeps turning. Avoiding catches in this way allows a turner to work with much more confidence.
Safe Drivers are also excellent tools when turning spindles that the turner wishes to flip around while working on them (switching the work piece so that the headstock end becomes the tailstock end). The machine does not have to be stopped to perform this operation. Merely loosening the tailstock pressure allows the piece to stop spinning so it can be flipped over. Tightening tailstock pressure will then start the piece spinning again.