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| AdeV:
Cheers chaps :) Ralph - in total, probably 6 hours today. If it had occurred to me that I didn't need a nice finish, I could have probably saved myself an hour. But what the heck, it's all good practice. |
| Dean W:
It's really coming along well, Ade. (And thanks for all the good pics!) --- Quote ---Here we are after the spotting work is done (including some idiot lines) --- End quote --- Idiot lines my eye. That's playing it smart. Idiots can't do this kind of work. --- Quote ---So, it's a shame it's going to be hidden away under the oily bits of the engine... --- End quote --- Somebody will see whatever you do in there, some day. Just think, when another fellow takes this off some time in the future, he's gonna think, "This guy did nice work!". Dean |
| AdeV:
Cheers Dean - actually, I used the phrase "idiot lines" in the same way as you'd use "idiot lights" - i.e. quick & dirty warning system. However, I've done some pretty idiotic things in my time; and even with the mill... so it's as wise to be sure.. Anyway, a very brief update tonight. Something that's been bugging me for a while is the one-shot oiler on my mill. It's never worked properly, and usually I'd get about 1/16" of movement on the handle if I used it. Since I've had the mill for 6 months now (yikes!), and it's never been properly 1-shot oiled, I decided I'd better do something about it... And besides, it's good for procrastinating when you're not sure what to do next... The problem with the oiler was obvious; the pump shaft is bent at the top, causing it to jam hard on the oil outlet doodah. So, the doodah was removed, and since I can't get the shaft out to straighten it, I decided to open up the port a bit to give it some room. In the pic, I'm just roughly centering it by "hanging" it on the 8mm drill bit, I then dialled it in properly, and reamed it out to 8.3mm. As this proved to be totally insufficient, I chucked it up again & ran it out to 9mm; that seems to have done the trick. So, by the time that was back on the mill, and one-shotted (the handle still hasn't come all the way down, so maybe there's a blockage too? Still, the knee seems easier to move now, time will tell), I'd decided what to do next: Drill the long holes. This involves canting the head over 90 degrees, as with the wax model. Only this time, I wanted to be a bit more scientific about setting the head up. So, I started by getting it roughly right, then using a dial gauge running on a cutter shank to try to get rid of any up-down differences: This wasn't easy, the cutter seemed to have some run-out/taper in it, and I was getting bored.... so I decided to try another method. I loaded the big drill up, then set my longest square on a 1-2-3 block. I positioned the knee so the end of the square was roughly on the centre line. Next; set the dial gauge up so it's at the exact (by eye, admittedly) same height as the square on it's 1-2-3 block, then set the centre line somewhat more accurately, thus: Now, move the square to the end of the table (I suppose the dial indicator would have worked just as well, and the magnet would mean I didn't need to clamp it like I did with the square... ho hum): Howzabout that? About 3-4mm low. So, I just spannered the head to the right angle by eye. I figure if it's within 1mm over 600+mm, that's pretty accurate... Question to anyone reading this: Is my method of setting the head angle sane? I'm not sure how much droop there is in that drill bit, and I'm not entirely sure how to measure it. Bear in mind the drill bit is tapered, so I can't use an edge with any accuracy... Any suggestions on how to be absolutely certain I've got the thing dead level would be much appreciated. |
| Stormin:
--- Quote from: AdeV on March 22, 2010, 06:18:42 PM ---Question to anyone reading this: Is my method of setting the head angle sane? I'm not sure how much droop there is in that drill bit, and I'm not entirely sure how to measure it. Bear in mind the drill bit is tapered, so I can't use an edge with any accuracy... Any suggestions on how to be absolutely certain I've got the thing dead level would be much appreciated. --- End quote --- Not an expert but I reckon there's a reasonable droop in the drill bit too. How about a cheapo laser pointer mounted in the spindle and set a target near to the pointer then further away on the table. Similar to the way you've done things but gaurantees a straight line to work from. |
| DMIOM:
--- Quote from: AdeV on March 22, 2010, 06:18:42 PM ---.....Bear in mind the drill bit is tapered, so I can't use an edge with any accuracy... Any suggestions on how to be absolutely certain I've got the thing dead level would be much appreciated........ --- End quote --- Not sure how practical this would be, with (a) overhang and (b) taper; but as food for thought : Take a block of, say, aluminium - might only need to be, say, a couple of inches cube (block needs to be long enough in X to span several turns of the flutes of the drill). Secure block to table and drill by feeding the full length of the drill through it. When the shank end has been reached, it should be drilling at the biggest diameter. Make certain the block is still well anchored and that the hole hasn't gone visibily out of round. With the spindle stopped, carefully feed the table back so as to withdraw the drill. When you get back to just before the tip, if there was no taper, the block should still be tight to the drill. If there is taper, it won't be tight any more, so loosen the clamp and then shim up the block (need to lift it squarely) and check if the amount of shim to get it to touch the bottom of the drill matches the specified taper. If you don't know the taper figure, with the block sat back un-shimmed on the table, slide the un-clamped block in and out on Y and clock the difference and halve it, then the shim in Z should be the same. One thing I'm not sure about though is how much whip you might have after drilling through such a short block ...... Dave |
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