Hi Guys,

In response to my post in "todays tool gloat" !

A little while ago I needed to drill some 2mm diameter holes in some 8mm diameter silver steel rod as accurately on the centre line as I could get. Not having a suitable clamp in order to do this, I made a finger plate from what was an off cut from a large angle iron section.
The 100 X 100 X 15 mm angle iron was cut with an abrasive saw to give me a piece 75 X 80 mm by 15 mm thick. This was then faced off on the mill with a fly cutter, mainly to remove the rust and scale on both sides. I made no attempt to machine to a specific thickness and ended up with a piece of material just under 14mm thick.

The pictures show the plate, the finger and the knurled brass capped screw, I put the brass cap onto the end of an off cut from an M6 bolt and put a brass stud in the other end of that to reduce marking when tightening it down. The other screw is a common hex cap screw.
I cut the "V" with a 16mm end mill, holding the work piece in a "V" block so that it was angled at 45 degrees. Again I had no specific depth to aim for. I think that I did it with six or seven passes of about 1mm with the cutter running at 5 or 6 hundred RPM. The "V" groove in the finger was done the same way.

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Views of all the components of the finger plate. The small hole in the finger is the drill guide hole, used to prevent the drill wandering on the curved surface of the silver steel rod. The three holes are tapped M6 and allow the finger to be placed to suit future work.


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The finger, 80mm long, was also made from the cut off leg of the angle iron. All the threads are M6, so you can judge the sizes from them.

The thumb screw brass cap was turned from a broken shear pin found in the scrap yard. I drilled and threaded it first on the lathe, then screwed the M6 stud into it after applying super glue to the threads. Then I used an M6 split die to hold the screw whilst clamping it in the three jaw chuck, skimmed it down to clean it up, Knurled it and did the chamfers and pattern on the top. Turned it round, re-chucked it, drilled the end 3mm and super glued a brass plug in the end.

The slot was drilled at each end and along the length 5.5mm and finished with a 6mm slot drill. That little notch in the middle of the slot edge was because I caught the hand wheel as I brought the drill down. I had forgotten to lock the cross slide

Thanks Guys, all comments welcome, good or bad.
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