I might be able to find info if you wish, and FAX to you if needed. There are some small but effective drill point sharpeners out there for real cheap like "Drill Doctor", some of those "General" add ons to a bench grinder, or Lisle type grinders.ĭoing by hand is an art, but whn figured out, is absolutely invaluable. i did this a few years back, say 15, before I bought a drill point sharpener. There is a set-up method for using a KO Lee for drill point sharpening, but it requires a very small "hollow" wheel, some ticky angles, and some patience. otherwise you drill with one edge only, and either chip the cutting edge, or drill oversize. the key point is to keep the chisel point centered and the drill tip angle the same on both sides. Machinery's Handbook has good diagrams for drills. It not only saves you money, it will also enable you to grind better performing tools for use on the lathe and mill. This prevents the tool from "grabbing" in the materials. This helps assure angles, and centering of the chisel point.ĩ0 degree included (45 per side) for wood and plasticġ18 degree (59 degree on each side) for steel and softer materialsġ35 degree for Stainless and harder materials.įor soft materials and Brass, you will need to reduce the rake angle on the bit, or grind off the cutting edge to the flute a bit. The best tool to have on hand for sharpening drill bits is a starrett or general drill point gauge. Your hand ground bits with practice should be fine for most work but always center drill first and drill a thru hole after at least the thickness of the web of the next hole size. ![]() Split points are 135* and are similar to regrind cept the web splitting. Half of this is 59* for a standard drill bit. The finnished product should have 2 lips of equal length and the chisel edge in the middle should be at 118* angle to each chisel edge. Then turn the grinder on and take a light cut. Practice this a few times till you get the feel of how the 2 lips are shaped. The further you roll it you should tilt it up only slighty for the 12* relief. Follow it's contour by rolling the bit in your fingers. With the grinder off place the bit on the center of the wheel and looking down on the bit the cutting edge or lip should be horizintal to the grinder wheel. It worked beautifully, the tool cut like a son of a bitch, in fact I made several which did the job until we got some proper ones.Get a largish drill bit that has not been reground but is dull. I then heated the whole lot up and let it cool gently, then I polished it till it was bright, I then warmed the "tool" till the and watched the colours "flow" to the end intil it turned blue, again another skill learned as an apprentice, I then plunged it in to oil to quench it. Then I ground the end to the required shape to cut a thread. I then got a cold chisel, ground it so that I could braze the piece in to a slot on the end. If you are dealing with more resistant tiles (e.g., stoneware tiles) or if you. We had some Ridgid pipe threaders, I got one of the removable thread cutters, put it in a vice and snapped a piece off. You can sharpen this type of drill bit with a regular file or a diamond file. The workshop had a brand new lathe but the dip **** engineer in charge of procuring supplies had screwed up on buying lathe tools, anyway the drill rig needed a left hand thread strainer to screw on the end of the drill string, could we make one, hmmm says I let me see what I can do. We had set up an onshore facility to process oil from the offshore platform. ![]() Usually, you’ll only have to adjust the head on one which has been heavily used. ![]() ![]() Mine was made for me so you'll have to hunt for one.Īs for drill bits, clearance clearance clearance is the phrase, the proudest part is the angled cutting edge and the rest of the drill curves back away from that cutting edge to allow clearance for swarf to get clear of the cut.Ĭlick to expand.Bit of fred drift, out in Egypt desert, Zeit Bay, winter time, colder than a witches tit. Twist drill bits- Standard drill bits are the most easily resharpened. Simply put the thing on the rest and roll it across the face of a spining wheel with the ball of your thumb - it cuts the wheels nice and straight avoiding chatter and vibration in use. To keep the wheel in good condition, invest in a dressing tool, the single point are the best for a bench grinder, consisting of an industrial diamond brazed onto a bit of round bar. Aiming where you put the time and or money with yield greater resu. Just throwing either at a job will get it done. How much more a baby wheel in one of those gadgets? Investing in a job requires time or money. Those gadgets are really no substitute for a bench grinder with a fine to medium grit wheel and when sharpening drill bits even they soon get a groove round them and the wheel needs dressing. such as this on e-bay, which has a very useful linisher attachment good for wood chisels and plane irons as well.
0 Comments
Leave a Reply. |