![]() ![]() I think this would increase the time taken by several orders of magnitude, as well as vastly increasing the danger of splitting the board in half along a row of holes. This is completely unrelated to the OP's problem, though.Īlso, I don't know anyone who centerpunches the PCB boards they are about to drill. Do some Google research on "masonry nails" + "tempering" + "quenching" first - you'll find a lot!) When you're done, heat it red-hot again and quench in oil - it'll convert back to a very hard state. Grind it in a drill press with a file, or on a bench grinder, or even a belt/disk sander hacksaw it, file it, even heat it and pound it flat on an anvil and sharpen it, etc. (You can even make decent tools from them! You have to heat them to cherry-red with a propane torch and let cool slowly - this 'converts' the steel to a more workable form. A nice cheapo alternative is a masonry nail - they're made of good (very hard) steel. In iron/steel, use a prick-punch and then a center-punch - every hardware/home store carries them, and they're cheap. In soft metals (brass, aluminum) a nail is fine (always wear eye protection when hitting metal into metal, though!). (In this case, the drill bit will flex the way you WANT it to!) In wood/soft materials, just use an awl, nail, etc. Twist drill bits will self-center in that dimple, even if you're a little off. In wood or softer materials, or with fat bits, you don't notice this - but with thin Dremel bits, going into metals, you've got the worst of all worlds - a thin (flexible) bit, and a situation where 1-2mm is a full hole diameter or so! It'd be like drilling a finger-sized hole nearly 1/2"/1cm away from your mark! SOLUTION: center-punch your mark! That is: make a dimple where you want your hole. The spinning tip hits the workpiece and, unless it's perfectly symmetrical (an impossibility), one side will dig in slightly more, and the bit will flex slightly. ANY rotating tool, particularly a drill bit, is almost guaranteed to "walk" slightly. You need to "center-punch" your holes first. This is actually more a technique problem - and easily solvable. ![]() You should attach a strong one or several of the "normal", weaker ones (as I did). If the press always deviates to the side, then let's make the deviation permanent! The fix was easy just attach a rubber-band! It pushes the Dremel body against the press's arm, completely removing the lag. I wanted to return it to the store, but I still needed a simpler way of drilling. When the rotating bit starts touching the PCB, the rotation makes the Dremel deviate 1-2mm (the lag) to one side, and you drill in the wrong place. The press has a lag of maybe 1-2 mm, which seems little but is enough for you to drill completely out of the spot. Well, I must say that it was rather disappointing, at least for the price (~60euros). Dremel's ads are always mentioning the excelent precision of their tools, and I thought that would be handy for PCB drilling. Then one day I saw this "Dremel Work Station" on sale, which is basically a drill press with a few extra features. I had a Dremel but I didn't use it for that, because I was used to the heavier driller. This is probably going to be the shortest instructable ever but, hey, I'm new to this :)! I used to drill my PCBs using a normal, heavy driller (I guess that's why the mm tick bits usually didnt last too long )). ![]()
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