WELCOME TO GY-ROLL LTD
Gy-Roll twin spindle and multi-spindle heads are specially designed for use with small self-feed drilling units. These self-feed drills are primarily intended for the drilling and tapping of small holes. As it is more often necessary to drill a group of small holes instead of a single hole and since such groups are often on close centres, it is important that a head specially designed for these units be capable of drilling on the closest possible centres. The minimum centre distance for Gy-Roll heads is approximately twice the maximum drill diameter.
Since the heads may be run at high speeds, particular care has been given to the design of the bearings for the internal gearing and spindles. All journal bearings are precision ground and needle bearings have caged rollers so that friction and subsequent wear is kept to a minimum. Axial spindle load is taken by a roller thrust bearing with a rating at least three times greater than a ball thrust bearing of an equivalent outside diameter.
Standard drilling adaptors and reversing tapping adaptors are supplied to suit most self-feed drilling units and air motors. Special adaptors for other units can be quoted for. The heads can be supplied for general workshop use with a taper shank for fitting directly into a drilling machine spindle or with standard flange or spigot locations for adapting to a drilling machine quill.
The screw back type of collet used in Gy-Roll heads provides the maximum drilling capacity in relation to the spindle diameter. The type 950 and 1250 heads can be supplied with either the screw back type of collet or with spindles to suit automotive drill adaptors.
The lubrication system in all Gy-Roll heads is designed in such a way that oil is released by capillary action from reservoirs as and when it is needed. The oil reservoirs provide oil to the spindles with the head in any position from vertical to horizontal. The oil is of a standard motor grade which is easily obtainable.