Where there are applications for heads where the hole pattern can not be attained by means of the standard adjustable heads, fixed centre multi spindle heads can be provided. These heads are specifically made to suit any form of hole pattern. Maximum collet capacity and minimum centre distance for the type, 400, 650, 800, 950 and 1250 fixed centre heads are the same as those for the twin spindle adjustable heads.
For economy in manufacture, availability of spares and early delivery, many parts such as spindles, gears and bearings etc. are common to both the standard adjustable and the fixed centre heads.
When requesting quotations or ordering Gy-Roll fixed centre heads it is essential to supply the following information:-
• Drawing of component to be drilled or tapped showing hole pattern centre distances.
• Drill size or tapping size.
• Name, make and model of the self-feed unit that is to be used. If it is a unit that we are not familiar with, full technical details will need to be supplied.
When accurate hole positions are required, it is always necessary to support the drills in close proximity to the work by means of drill bushes. Under these conditions it is therefore essential that either bushed jigs or bush plates are used with both adjustable and fixed centre heads.