Is it just me or do all of the new bits just suck ? Seems like they go dull before you finish the hole even with the use of a cutting oil. Tried a number of bits from Sears an/ or Ace with no great luck. Who has good bits ??
I use the desalt bits with good results , remember drill speed is important , slow down on speed , I go slow speed just enough that the metal comes out as a coil like string...learned this years ago and my bits last pretty long......
Are you holding the drill motor and letting the bit work at it's own pace or are you leaning into it like a madman on a mission....lol.....that makes a huge difference, also proper size for starting the job makes a hole start easier.
A good rule of thumb to remember is, if the finished hole is to be any larger than 5/16", always drill a pilot hole with a 1/8" bit.
I'm sure you already know this, but not only does too high of rpm's shorten a drill bits' life between sharpenings, but also letting a drill bit "dwell" at the start of the cut. Within reason; drill bits can stand more pressure than not actually biting in at initial start. Also, if you don't have one yet, a drill sharpening gage could make a big difference. I know those sets you get at places like HF and Lowes, etc are attractively priced but good ol' U.S. made drill bits are more dependable with their heat treatment process.
Stay out of your local hard ware store. It`s all about the cheapest price. Sears and the big box lumber yards have been that way too.. I buy mine at Fastenal. They cost more, but they are worth it.
Buy your bits at an industrial supply Get cobalt split point bits not cheep but a lot less aggravation
I was frustrated with my drill bits at the shop. I bought a letter set and a number set from Fastenal that are nice. And I bought the fractional set from Mac because those are the most used and Mac warranties them. I know most guys don't have access to the tool truck though, so I would go with Fastenal. And remember, cutting oil every time!
My son got me a nice set a few years ago, they are holding up just fine. https://littlemachineshop.com/products/product_view.php?ProductID=2827&category=
I bought a cheap bit sharpener at Harbor Freight and it does a pretty good job.. Sharpens up to 25/64ths bits...
All good answers here. Just remember, a Drill Doctor is your friend. I have a hundred or so bits that I've collected over the years (most are cheapies). One day I decided to sort them all then spent about an hour sharpening every one in my Drill Doctor. Put 'em all in a nut and bolt cabinet and now I've got a multitude of sharp bits at the ready any time I need one.
I use high speed steel. Works great and they dont work harden like the coated bits do. Also another trick I use is to take an arkansas stone to a freshly sharpened drill bit. On the cutting edge after sharpening it usually leaves a small burr. When drilling that burr rolls under your cutting edge. So to get the burr off I take the arkansas stone and LIGHTLY stone the face of the cutting edge. You wouldn't believe how well this works. Also cutting oil or sythetic coolant does wonders.
I use Irwin bits that the Matco guy warranties. They are the flatish style that also work good for drilling out spot welds. I just get new when they are dull. For regular cheap bits I sharpen them myself and always run them with a bit of a hungry taper for fast cutting. Most bits don't take a big enough chip and create a lot of friction. When you have two spirals of metal coming out life is good. A note they can be quite grabby and watch out for spirals and cuts to your hands. I think most manufacturers want to error on the side of safety at the expense of the life of the bit.
I like the cobalt bits & buy them when they are on sale. Not the cobalt coated. The cobalts cut really well & stay sharp. Walter bits are pricey but they are among the best. Keeping the bits sharp, cutting speed & lubricants are important as others have mentioned.
As it has been said...Drill bits are like this...you get what you pay for. I have a number of sets from our main hardware/auto store and hey for $39 to get a number/letter/imperial set it covers a lot of general shop drilling to a reasonable precision. But always expect one or two or more to be sharpened awkwardly/or not run true. A good rule of thumb when drilling to a certain size is drill a test hole in some scrap of same material and measure to verify it is not to big or small and reasonably round (burring should be minimal as well as pressure applied minimal). If you have to exert a lot of pressure the bit is likely dull or inferior. As mentioned step up don't go from 1/8 to 5/16. Go 1/8 - 5/32 - 3/16- 1/4 - 5/16. This will more accurately center your drilling as well. Clamp or anchor your work when drilling as moving work can damage the bit and injure you. So many details...
Center drills are your friend. Another thing; when accurate locations matter, if relying strictly on a center punch, make sure you hit them straight on or they can drill off-location.
With alot of the metals coming from China now days and them buying anything and everything to melt to make new steel, there are more and more impurities in the steel. Hotroll is especially bad. I cut a bar once and hit a ballbearing in it that hadn't got melted.
Surprisingly, the gold ones from Harbor Freight are not too bad. I have a bunch of industrial ones, and the HF bits seem to stay sharp just as long before I need to use the Drill Dr. We also buy their step bits when HF has them on sale and they ain't too bad either. Don
You know the drill around here... 24-7 service with a story, advice and a pic or two. Nice avatar Terry period.
I have a veritable shit load of drill bits, maybe more than I can use in a lifetime. Regular HSS, cobalt, TiN coated and so on. When I need a drill bit for a paying job, I'll figure anywhere from 3 to 12 into the job. Smaller diameters are cheaper, those are a dozen at a clip. Cheap bits, I toss out. Anything from 3/16" and up I toss into a box, when I have endmills sharpened, I have the drill bits done at the same time. I buy mostly Morse or Cleveland drill bits, NY Twist Drill is local and good too. Odd sizes I may have to go import (from MSC) but some of the TiN coated ones last a long time.
I have drilled a gazillion holes as a machinist. The best bits I have found and used are Cleveland, Precision Twist Drill (marked with PTD on bit), and lately I have bought from McMaster-Carr. I always run my bits 200-300 rpm slower than recommended on the drill speed charts.
hit a ballbearing in it that hadn't got melted. I had a similar thing on a GM truck rear brake rotor. Supposed to be cast iron. There was a partially melted nut in the surface finish..
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