ARGUMENTS IN FAVOUR OF THE GUIDE BUSH WITH ROLLERS

• It permits to avoid any problem of untrueness in connection with usual revolving bushes, because of its direct contact with the material. The concentricity between material diameter and outside/inside turning diameters of the workpiece is warranted.

• It avoids any axial seizing-up when cutting large chips or when chasing a thread.

• It is preloaded by its setting system. This, however, is not the case for the collet of a revolving bush. By radial efforts, the collet with no preload may open a bit (clearance of the thread, elasticity of the collet material).

• It makes no problem with the emulsions. More than 50 % of the users run the machines with emulsion. The proportion increases still.

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• It has no rotation speed limits on the present machines on the market. This is related to the fact that the rotation diameter of the rollers is smaller than the ball-bearing diameter of usual revolving bushes.

• It permits to correct slightly the geometry of smooth materials, like Titan, Aluminium, etc. by clamping it a little more than usual. The action will result in “rolling” the raw material. The guide bush can be moved on the material axis, so that it can be brought nearer to the tools or moved a little away from them. This, however, cannot be done with the revolving bush, as its axial position is fixed.

• When the wanted precision of your workpiece requires a strong adjusting strain on the guide bush (either fixed or revolving), your guide bush may frequently seize up at the headstock spindle return, for example at thread chasing or when you are deburring a thread. When the material advances in the bush, it shows a tendency to open the bush. The return motion, however, has an inevitable self-clamping effect. The guide bush with rollers permits to avoid that situation.

Lubrication

• The lubrication system with filter prevents swarf from entering into the interior of the guide bush causing premature wear of the carbide rollers. Guide bushes which are used without filtered lubrication will not be subject to the manufacturer’s guarantee.