It seems that anytime I try to a job like drilling a hole to be tapped either the drill bit is junk or it just breaks. Is there a drill bit set out there that is affordable and still be of quality grade? I'm looking for a set that goes to 1/2 inch and is both numbered and lettered. I bought a set from Northern Tool but they are junk.
Northern Tool bits are probably made in China.
You need bits made in the U.S.A.
I have a Union Butterfield set, an older Craftsman set and I pick up Hanson drill bits at estate sales.
Alas, no. Bite the bullet and get a professional set from an outfit that provides tooling for machinists. Cheaper in the long run.
I uses a Drill Doctor to resharpen all my cheap drill bits. That and use of a cutting oil on the bit makes a big difference. I find that the Chinese bits are of the proper hardness, but are often not sharpened properly. The other thing is don't use too much pressure. Let the bit cut, don't force it. Broken bits are caused by pressing too hard.
I was hand sharpening drills long before Drill Doctor came out. Steve is correct that the Chinese bits leave the factory improperly sharpened, but that is easily corrected with a Drill doctor or a good grinder this set works for me
and plenty of this stuff to keep the bit cool.
https://www.harborfreight.com/catalogsearch/result/index/?dir=asc&order=EAScore%2Cf%2CEAFeatured+Weight%2Cf%2CSale+Rank%2Cf&q=cutting+oil I don't know about quality but I have been using my set for 17 years now so none of the bits are as long as they used to be
Steve's right, even a cheap drill bit will do the job sharpened correctly and kept cool (that's what cutting oil does, carries the heat away from the cutting edge).
Depends a lot of on what you're drilling and what tool you're using to do it, too. I've had a few really cheap bits that I tried in my lathe and when they're chucked in the tailstock and the work is turning (rather than the bit turning as when chucked in a drill motor), you can see them spring like crazy as compared to the equivalent size high quality bit.
A quality Fraction/Letter/Wire size set runs a few hundred bucks now at full retail. If you look at that as less than $3 per bit it makes it a little easy to stomach. If you shop around sometimes you can find them on sale.
I picked up a Drill Doctor 750+ a number of years ago. I dont think I ever used it. I dug it out from the back of my shop under other tools I dont normally use and tried to sharpen a bit. Took a few to get the 118 degree angle set up. Seems to work ok on larger bits but the smaller one it dosent seem to grind even. I have always hand sharpened bits on my blue stone and have very good luck. I will let you guys know how this works out for me.
I work in Aerospace and are preferred drill material is cobalt. Mind you we machine Aluminum to Inconel with the same drill material. Cobalt drills are cheap and hold up decently to hard metals. Carbide is to brittle and will break easily if your equipment isn't on center.
We use Greenfield or Precision Twist Drill brand drills.
Cobalt drill bits will cut a triple gear about sixteenths of an inch at a time using oil. I use them for equalizing gear weight. Many tools from China work OK----many you think are US made are not. Every garage sale I look at might have partial sets of good bits for cheap.
I have been sharpening drill bits by hand longer then I can remember. I was in Tool & Die for about 40 yrs. I have drilled holes with a .012 (#83) to 1.5" I have never broke a bit larger then 1/8".
If the bit moves when you drill in a lathe, either it's not center drilled right, or the bit is sharpened off center. It should never move.
Now that I got reading classes, I can sharpen them right again. lol
I do not like a drill bit sets that holds all drill bits in one case. I have three sets of bits, each set has three box's, number, fraction, and letter. One set is sharpen to drill wood, one for plastic, aluminum & steel, and another for brass. also a micro bit set #61-80, which I use in my hobbies. (I've never tried to sharpen any of them) I also have two sets of Tap & drill bit. And small bins full of odd bits.
I have only high speed steel drill bits. I only use carbon when drilling concrete.
Pat, I wasn't clear with what I posted. When I say I can see a cheap bit spring, I'm talking in terms of rotation, not moving off center due to it walking. Even the best bits will walk to a center point.
Pat Clark just said,...."high speed drills". Probably the most important thing I learned in high school machine shop. Our shop teacher, Mr. Murray said to always buy "high speed drills". That particular designation really has nothing to do with "speed" or rpm and is somewhat misleading. It has only to do with the fact that "high speed" designates the quality of the steel. If a drill is not marked "HS" or "HSS", don't buy it!
Pat: I find the micro-bit sets are great if you smack a finger nail, Just spin it between fingers to drill through the nail then dunk it in H2O2.. relives all the pressure then your finger quits throbbing! other than that I don't have a chuck small enough to hold the bits.
"Is there a drill bit set out there that is affordable and still be of quality grade?"
No. You get what you pay for.
For price considerations, best to look for a nice, used, older set of American made drills. Obviously here, used should not mean used-up, or abused. Got to believe that there are some new-old-stock drills on eBay. Maybe not sets, but you could build a set that way perhaps, if shipping doesn't kill it.
You may want to look at setting that thing for 135 degrees of angle point, AND drilling a bit of a smaller pilot first, AND, do not drill DRY always use a lube.
People who do find that just about any drill material cuts better and lasts longer, especially when drilling alloy steels. "Longer" however, can be measured in minutes (grin)
One of the issues with Cobalt is if you don't do the pilot, and do use dry, the cutting edge just explodes out (if it hits something like a carbide grain area) --whether made in Philadelphia, or Milwaukee, or Xian, or Bulawayo!! Simple physics..Cobalt are around 67 in hardness on Rockwell, high carbon alloy goes brittle at about 63 Rockwell...it's a rocks paper scissors kind of thing
(Message edited by George_nj on June 26, 2017)
I once received a cheap set of bits as a door prize. Then trying them out this 1/8" bit curled right up. I tossed the rest of them. You get what you pay for. Mike
Wow, Never had one do that before! I once bent a 3/8 drive ratchet in a nice U shape. My mother in law got it for me from Fingerhut as a birthday gift. Never told her what happened.
I've always sharpened my own bits on a grinder OK but with my 70+ eyes it's getting harder to see the smaller sizes.
Is the Drill Doctor a good deal and which model is OK?
I have a drill doctor. I struggled with large bits. Which is opposite of most people. What I found out if you tighten the mounting chuck to much you change the bit's position, and it does not sharpen right. Now with just a snug bit I can sharpen the bits quickly.
Here's my "drill doctor", (Internet photo, actually mine is nice & clean).
Invest in a set of Dewalt cobalt twist drills, mine have lasted a long time.Remember to treat drills bits and files like precision equipment
Hey, Now That's a Drill Surgeon!!
It's a beautiful thing Gene!