I needed to drill some holes pretty much dead nuts on some tubing (on the digger) and I've never had a lot of luck going through tubing and getting it right on. So here's my low buck fix. The "fixture" is nothing more than a piece of tubing I split in half and welded another piece of tubing to. I mark the tubing to be drilled on the car- drill the hole undersize (3/8" in this case) I get it pretty close and drill through both walls of the ch***is tubing. I align & hose clamp the "fixture" in place - grab my 1/2 drill bit and blast away. Having the bulk of the material already removed makes the drilling quick and minimizes wear on the throw away fixture.
awsome idea i love homemade tools alot of times they work way better than the store bought ones...good job!
Good idea, thanks for sharing.. While we are on the topic of drilling holes.. has anyone used one of the Drill Dr bit sharpeners? are they worth the money or just infomercial hype? Brian
we used em at work they work pretty good. they are GREAT if you have to shorten a bit for tight cleearance or break one and want to keep it. very hard to get the right angles by hand.
The only downside I've seen to the Drill Doctor is that it doesn't work well on small bits (<1/8" or so). It allowed me to fix the f-ed up drill bits that those Chinese kids sharpened wrong at the factory. They work much better now. Cool jig, by the way. How'd you get the two tubes welded perpendicular?
Yeah, most cool. Tacking it in the drill press ought to work ok for alignment purposes. (Provided the drill press is really square - a lot of them aren't.) Keep your eyes open, a lotta times you can find HSS bits 1/8" & down on sale at very low prices. Sears does it and you get a good quality drill individually packed. Spend $5. - $10. on a bunch of them and replace when dull. I've been able to try 5% cobalt, Tn and Zn drills that way. Using the small sizes gives a good indication of how the big ones will do and whether it's worth springing for an index full of a particular type. I have a Drill Doctor and really like it. The hardest part is getting it out. Probably ought to set it on the bench and have it ready to go. Anyway, as said, cool fixture. Simple, but the simple stuff that does the job is the hardest to figure out....
How often do you guys sharpen your bits? Cool fixture. That's a really great idea. Work smart, not hard, right?
The smart-*** (and correct) answer is, "When they're dull." If you're thinking the drill in use is not drilling as good as it should be, it's time to sharpen. If you're new to the drilling & fabbing bit, you won't have any problems deciding when the drill is dull. Even so, don't just keep drilling with a dull drill. And . . . if you've got an index full of less-than-sharp drills and either get them sharpened or get a new index full of good quality drills, it'll be a whole new world. Sorta like when you finally sharpen your pocketknife. That's when you realize how dull it really was....
Aah. Enlightment. I didn't know if there was some "every 3,000,000 revolutions or 3 inches of penetration" rule of thumb.
A lot of guys are very good at sharpening drills by hand. I do it from time to time on the large bits, but prefer the Drill Doctor. You can tell you've done a good job if the bit is cutting two strings of metal and not just one. One string indicates one side of the bit is cutting and the other is not. The Drill Doctor cures that. When you see one string coming off, your drill bit is cutting an oversize hole. A correctly sharpened drill bit will cut two strings and the hole will be the proper size. Precision in hole sizes is accomplished by using a reamer for the final cut. Extreme precision requires the reamed hole be lapped to size, but it's not something to worry about. Hot rodders don't need that degree of accuracy. A skilled person can make a drill bit cut undersize or oversize simply by the sharpening technique used. Part of that due to drill bits are actually a few thousandths undersize from what their label indicates. When both of the drill bits cutting edges match precisely you'll have a slightly undersize hole and as noted above, get a mismatch and you'll have an oversize hole due to the one side cutting tends to drift out a ways so the non-cutting side is either just riding on the cut surface or taking a minimal cut. One thing that can dull drills fast is enlarging a hole by a small amount. If you're going from say a 3/4" hole to 1" only the outer 1/8" of the 1" drill bit's cutting edge is doing the cutting and if you apply the usual amount of pressure the outer edge of the 1" drill bit will fail. Going from 3/4 to 1" can be done, just take it easy on the feed pressure and be generous with the cutting fluid. A slick way to judge drill speed on a variable speed hand held drill motor is to watch the flutes of the bit under a fluorescent light. The fluor light acts like a strobe and when the flutes are (visually) standing still the speed is about right. Found true on the smaller bit sizes - 3/16" & under - and probably true for the large bits as well. The fluor light trick helped extend the life of the drill bits when I was drilling a few hundred 1/8" holes in a re-pro 32 frame. More than you pobably wanted to know, but I have a little time this morning. Waiting for the garage to warm up so's I can ***emble my new hydraulic press.
I squared the ends of the small tubing then clamped it in the vise - checked it - tacked it - flipped it - tacked it again. The small tubing I had was just a wee bit undersized on the ID - so after it was welded I ran the drill bit thru it (I had to drill that cross tube anyways). Seemed to work real well.
A slick way to judge drill speed on a variable speed hand held drill motor is to watch the flutes of the bit under a fluorescent light. The fluor light acts like a strobe and when the flutes are (visually) standing still the speed is about right. OK so we're talking 60 times a second for the electricity (50 cycles for you Brits) and that comes up to 3600 times a minute. But there's 2 flutes on a bit so cut it in half and you're looking at about 1800 RPM neat!
Another thing for drilling tubing/pipe in a drill press.. Place the pipe in you press vice, take a fine file and lay a level over it, then keeping an eye on the level, take a swipe on the top of a pipe with the file. Center punch along your line you just made with the file and drill, this way you hit it dead nuts.
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