I purchased an indexer from forum member Rod Mell and to render it usable on my little mill it required a few alterations. As supplied the front and rear faces of the main body casting are machined but the sides of the base are left as cast. Great for a magnetic chuck and probably useable if held in a large vice but pretty much useless on my mill.

So I machined the edges parallel with and centred on the spindle centreline.

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Then I machined and spot faced a pair of hold down slots. Some of the paint and filler chipped off during the spot facing so I removed all the paint and most of the filler.

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The front and rear faces and their counterbores were not very accurate so I used my boring head for both flycutting and facing to improve those surfaces.

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I then machined a keyway and made a pair of keys to suit the mill's 12mm wide tee slots.

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The indexing plate threaded lock ring was poorly made, the internal diameter of the ring was the same as most of the spindle's thread OD with engagement of one thread when the ring was screwed up against the plate. A replacement was made from 4140 with holes to facilitate the use of a proper pin spanner for tightening. I also made a replacement rear ring. The original was a loose wobbling fit and its role is to set the end play in the spindle. The new ring has a few tenths clearance and end play is easily set.

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And then there is to my mind the most important modification, a spindle lock. Having come unstuck before when a workpiece rotated while milling with disasterous results, there was no way that an M12 threaded aluminium thumbscrew was going to cope with two horsepower. I toyed with the idea of some sort of split clamp that bolted to the rear of the casting then decided on the simple solution of using a split cotter. Machined from 4E cast iron and secured with an M8 cap screw, it locks the spindle solid.

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And finally, the reason for all this fooling around....

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Bob.
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