| Author | Message | ||
     Peter Wallage Rating: N/A |
Hi Harv, I came across the same problem some time ago. I too was unable to find a cross-point driver small enough for some screws I needed to undo, so I modified a plain blade-point driver. Not ideal I know, because it grips in only two of the recesses in the screw head instead of four, but it worked and I've used it several times. What I did was to take the thinnest blade-point driver from a cheap and cheerful market-stall set of "instrument screwdrivers". I've just measured it, and the blade is exactly 1mm diameter. I let down the hardness of the blade by heating it with a butane pencil-torch to a dull red and letting it cool naturally in air. Then I shaped the point to a vee spear shape with a very fine-tooth file till it fitted in the screws I wanted to undo, then hardened it by heating it to bright red and quenching in oil. The type of oil isn't critical, I used some car engine oil in an old film container. Hardening by itself would have made the blade too brittle, so I tempered it. I cleaned it with some fine rubbing-down paper, held the flame of the pencil butane torch about half an inch or so behind the tip and watched the colours travel up the blade. As soon as the blue colour reached the tip I quenched it again in oil. The colours travel quite quickly so you have to keep a sharp watch on them. I used the term cross-point rather than Phillips because some Japanese cameras, notably Canon, don't use a Phillips type cross head. Their cross head is shallower and at a broader angle, and the cross slots are thinner. I also made some drivers in the same way as above to fit several sizes of Canon cross-head screw. As I said, not the ideal tools, but mine work and so far, touch wood, I haven't chewed up any screw heads. Hope this is of some help. Peter |