Tired of drill bits breaking

[Scott Brandstetter]

Any suggestions on a good set of drill bits. As the title says, tired of them breaking. I've tried the typical big box store brands, never great success.

[Jerry Wright]

Diameter? material being drilled? Drill press or hand held dril? This info would help lead to an answer.

[Lee Reep]

I try to avoid carbon steel bits. I bought a huge set of TN (titanium nitride) drill bits a few years ago at Harbor Freight:

http://www.harborfreight.com/115-piece-titanium-nitride-coated-m2-high-speed-steel-drill-bit-set-1611.html

I was not expecting great results, but they are decent. I've never broken one, but I suppose if I had a 1/64" inch bit going into something like stainless or cast iron, I'd be doomed. My uses are primarily wood, and they have served me well. I do not try to sharpen bits, I toss and replace. I bought a huge, boxed, drill bit assortment from Woodcraft (Wood River brand) a couple years ago and it has over 100 bits of a large range of sizes, so plenty of replacements as my other bits dull. This set was brad point, and they also had a twist drill set. I am sold on brad point for woodworking, and also for drilling into drywall -- no wandering of the bit.

[Kent A Bathurst]

Any suggestions on a good set of drill bits. As the title says, tired of them breaking. I've tried the typical big box store brands, never great success.

Scott - you don't say what type of bits you are having problems with. Not too big of a stretch to guess standard twist drill bit............soooooo.............

In which case, Bosch makes a variety of them - different metals - different $$$.

I have had very good success with this index set. But - in the smaller diameters - 1/16" through 1/8" - I keep an inventory of backups. No way to put those through any hard use without the occasional snap.

http://www.amazon.com/Bosch-BL0029-16-Inch-2-Inch-Assortment/dp/B0000TZWMM/ref=sr_1_5?s=hi&ie=UTF8&qid=1426810522&sr=1-5&keywords=bosch+twist+drill+index

[ian maybury]

There does seem to be an epidemic of overly hardened and sometimes warped carbon steel bits about in the box stores and cheap DIY engineering tool supply places. I've had locally bought twist drills in sizes around 3mm for example snap off instantly upon breaking through in thin sheet metal.

Well made high speed steel items both wear much better, and while not unbreakable are much tougher - but there's carbon steel drills about (over here anyway) masquerading as high speed steel so the designation isn't always to be trusted. Try handling an example in a size around 5mm - you'll be able to tell the difference just by feel. Also by the sound if you drop both on a hard surface - they sound quite different.

Even good quality carbon drills are not bad if handled carefully, but HSS is a lot better. For twist drills try a professional tool room supplies place, and as the guys say expect to pay potentially quite a bit more. Better quality drills tend to be far more precisely sharpened, and to cut much more cleanly.

For brad point bits more or less the same applies. Avoid the box stores for anything except rough work (although Bosch DIY product while not great is often not too bad), and go specialist for the good stuff. Lee Valley seem to carry a range of qualities which is quite a nice illustration of possibility: http://www.leevalley.com/US/Wood/page.aspx?cat=1,180&p=42240

There are very competitively priced big boxes (typically a large flat white sheet metal box with a black plastic tray with compartments for the different sizes) of drills about. I have one of standard twist drills with the gold coating bought in the UK. Mine are not not bad, but of nothing like the toughness and edge holding ability of a good quality genuinely professional/tool room standard HSS drill.

Be aware that titanium nitride (gold) is just a low friction coating. It likely adds something in high wear situations, but can't make much difference on cheap drills/is probably mostly there to bling them up. It's quite likely not even what it claims to be.

It's well worth buying a few samples of a premium quality drill, especially in brad point. ;) Just to place yourself in the delicious dilemma of realising just how good and clean cutting a drill bit can be, and why before long you will probably be prepared to pay x5 the price of cheap drills. Something like Colt's best, or Famag HSS-G (not widely available in the US - http://www.fine-tools.com/holzspiralbohrer.html ), and (not tested by me) there's been good reports about regarding lee Valley's premium product too...

[Greg R Bradley]

I've easily bought $100K worth of drill bits in the last 40 years and I've learned it can be really hard to make generalizations. I can completely agree with Ian Mayberry on every point he makes.

It is very rare that any steel/wood drill bits from the BORG will be worth buying. Most of the brands will be garbage but then they go and have Milwaukee, Bosch, and even Dewalt Rotary Hammer Bits that work very well. Dewalt usually sells rubbish in the BORG but their Rotary Hammer, Made in Germany, bits are excellent. Hurry up and buy some as Stanley Black and Decker will find a way to screw it up eventually. When you find something they sell that is excellent, they will always turn it into acceptable on the way to turning it into garbage.

If you want a good set of premium grade HSS bits for general use including steel drilling, go to carbideprocessors.com and look around. Call them if you want to describe your needs and they will bend over backwards to help you out. Here is a typical starter set: http://www.carbideprocessors.com/13pc-jobber-drill-set-1-16-1-4-by-64ths-thunderbit-premium-grade-hss-triumph-099858/

If you are looking for some wood specific brad point, you could look at the previously mentioned LeeValley.com and find some bits made on the same drill blanks I just mentioned.

Don't forget to buy a 10 pack of the cheap garbage from Harbor Freight in 1/16" & 1/8", at least for the occasional time that you want a drill bit but you know you are going to destroy the bit during that one use........................... I always keep a pack on hand and buy them when they sell them for virtually nothing.

[Peter Aeschliman]

When you find something they sell that is excellent, they will always turn it into acceptable on the way to turning it into garbage.


Hahaha that was hilarious and true.

[Chuck Hart]

This is the second post I have seen this discussion. I buy Fisch drill bits. They are made in Austria/Germany and are of exceptional quality. Their forstner wave bits are the best out there IMHO

[Keith Weber]

If you want good drill bits, you'll have to pay for them. It all depends what you're cutting with them. Brad point bits are generally better for woodworking than twist bits. If you're looking for drilling metal, then you'll need a good set of twist drill bits.

It is so nice using quality drill bits. You can tell just by looking at them that they're going to drill better. Straight, nice clean edges ( on the sides as well as the tip), and no burrs. I've seen so many Import drill bits that were full of chips, burrs, and bends -- and they were brand new. Even the grind on some of them wasn't even centered or symmetrical, so the point was closer to one edge than the other.

I'm a big fan of cobalt drill bits. They're a little harder and more heat resistant than regular HSS bits, and do a much better job on tougher metals. There is a tradeoff between hardness and brittleness, though. Harder bits drill harder metals, but they're more prone to breakage if misused. Low carbon steel bits are less likely to break, but they don't work at all on harder metals, and they are prone to bending. To me, a bent bit is about as useful as a broken one.

My go-to twist drill set I keep in the woodshop toolbox is a Milwaukee 29-Piece cobalt jobber set (#48-89-0050). It's an awesome set, but they don't make it anymore. They're probably outsourcing everything these days too, so I can't really vouch for the new ones. In my machine shop, I use Precision Twist cobalt drill bits. They're good quality US-made bits. I have full sets in Fractions, Wire and Letter sizes. They can get a bit pricey though unless you get them on sale as I did. I opted for the shorter, screw machine length -- partly to save money, but also to increase rigidity and accuracy on my milling machine. I've also heard good things on Chicago Latrobe bits, but they're even pricier. All depend on how you want to balance the cost vs. quality equation. I also have a cheap, junky import set that I keep around just for when I need a small hole drilled in a 2x4.

Good drill bits shouldn't break unless you subject them to side loads or too much heat or pressure. Obviously, the smaller the bit, the easier it will be to break. With hand drills, it's more difficult to keep the drill straight, so side loads are much more probable. Small bits often break for this reason. Also when trying to drill hard materials, or with a dull drill bit, the bit often spins on the material without actually cutting. This will kill drill bits fast. The heat will built up rapidly, smoke will start appearing, and you will try to force the hole by pushing harder. Eventually, this results in broken bits as well. You should never continue to drill if the drill is not producing chips. Stop and sharpen your bit, select a more-appropriate bit type, or use a drill press for firm and uniform pressure.

Another problem with twist drills, is that they don't always want to drill the hole where you want it to go. This could be to following the grain in wood, or walking across metal until it starts the hole. Drill presses are easier on drill bits than hand drilling. If you clamp down a workpiece on the drill press, and the hole starts slightly off from where you intended it to, you should loosen the clamp and reposition the started hole so that it is directly under the quill before you tighten your clamp back up and continue drilling the hole. If you don't, small bits in deep holes can bend enough to break your bit. With metalworking, I always use a spotting drill bit to start the hole first. It's a pain, and takes more time, but your holes will always be right where you want them because the spotting drill won't walk like a twist drill.

The final point I'd make in terms of bit longevity is to pay attention to the drill rpm. Consult the tables for what you're drilling and the diameter of the hole. After a while, you'll get a feel for it, and won't have to look at the chart every time. But, if you're new to it, it might help prevent you from cooking a bit from running it way to fast or snapping one from running too slow in catchy material.


I was not expecting great results, but they are decent. I've never broken one, but I suppose if I had a 1/64" inch bit going into something like stainless or cast iron, I'd be doomed.

Lee, you're right on the money regarding stainless -- it does work harden quickly if you linger with the bit, and can be a real bear to work with. But, for what it's worth, cast iron is very easy to drill. A sharp bit should go through it like a hot knife through butter. The chips are just a little powdery, as compared to the long, curly strands you associate with mild steel.

[Jim Matthews]

I break bits when they're dull, and try to force them through.

A properly sharpened bit will cut a little with each rotation.
If you're forcing a dull bit, no chip will be ejected.

The chip carries waste heat.

If the heat builds in the bit, it's likely to fracture
at the weakest point, where the flutes start.

I would suggest two things,
separate bits for metal and wood.

Drill at the slowest speed that keeps things turning.
Faster isn't better with boring clean holes.

[Brian W Smith]

Look in your yellow pages for a "real" bolt jobber.Much in the way a real plumbing store is to Borgs......a bolt jobber will have the drills that keep industry moving in your area.They'll have good pricing and other stuff like taps/dies.....and bolts of every flavor.Probably a huge assortment of cutting and lubing fluids too.

Try to find a non-corporate.....Not fastenall,Grainger type.May have to ask around,try a machine shop or serious automotive joint.Good luck.

[Scott Brandstetter]

Wow, a lot of good info on bits. Sorry I didn't post it originally, I am speaking of bits for drilling in wood. I'm going to try a selection of those recommended and see if I can discover a favorite. Thanks for all of the replies.

[Tom M King]

For really small bits drilling in wood, drill down enough to load the flutes, and withdraw to allow the dust to clear out of the flutes. If you pack them too tight with nowhere for new drilling dust to accumulate, they will overheat quickly and break.

[Peter Kelly]

The bit sets at Harry Epstein are good: http://store.harryepstein.com/merchant2/merchant.mvc?Screen=CTGY&Store_Code=1930&Category_Code=DrillBitSets

Made in USA.

[Lee Reep]

Lee, you're right on the money regarding stainless -- it does work harden quickly if you linger with the bit, and can be a real bear to work with. But, for what it's worth, cast iron is very easy to drill. A sharp bit should go through it like a hot knife through butter. The chips are just a little powdery, as compared to the long, curly strands you associate with mild steel.

Keith,
Good to know about drilling cast iron. I've only drilled it at a friend's machine shop, and he was known to have a really crappy (and incomplete) set of bits. :D

[glenn bradley]

Good drill bits shouldn't break unless you subject them to side loads or too much heat or pressure.

I was hoping someone would mention this. Not so much an issue on the drill press but in hand drilling (especially when fatigued) having an inch of the bit in the material and then letting the drill motor wander off-axis while spinning the bit will fatigue almost anything ;-)

I have the Lee Valley 'lipped' bits and use them for nearly all of my woodworking tasks in solid woods. Due to the geometry that makes such a beautifully clean exit hole, these bits do not do well in stacked (ganged) items or plywoods. The lips tend to shear a nice clean disc at the exit of the first layer which then spins like a washer against the second layer. For this type of drilling I use carbon split-point drill bits which do fine for me since I use them so seldom. I have a Drill Doctor picked up for a song on clearance that touches them up if required. I have a set of cobalt bits that I use for steel and then the specific purpose bits like numbered, really tiny wire sizes and so forth. The best set for you will depend on what you use them for.

What I find amuising about myself is that I will hem and haw over $100+ for a 29 piece drill bit set but will spend that much in a heartbeat on a single router bit I need.

[Keith Weber]

these bits do not do well in stacked (ganged) items or plywoods. The lips tend to shear a nice clean disc at the exit of the first layer which then spins like a washer against the second layer.

LOL! I hate when that happens. It happens to me all the time using spade bits in plywood when doing construction building. It's especially annoying when you're drilling though 1-1/2" or 3" of dimensional lumber before you hit the plywood, and the wooden washer won't come out of the hole. I have to run and get my little pick set to fish it out.

[Tom Walz]

I had the guys in the shop make me some stubby drill bits. Regular bits cut down. I use them for one particular job where there is a lot of side load.

[Greg R Bradley]

Drilling a wide variety of sizes in a wide variety of materials can be challenging.

Some misc items off my desk from projects we've done.

What is the item sitting in the hole in the bolt?


309518

[ian maybury]

Normal 'grey' (graphite containing) cast iron is fine to drill, but watch out for the 'white' (also called 'chilled') variety which can very occasionally be found intentionally in parts requiring high wear resistance, or unintentionally in patches that have been allowed to locally cool too quickly. It's pretty much undrillable by any normal means without local annealing, and that's very hard to pull off, takes time and equipment and risks cracking castings etc. It's often the issue when normally very manageable cast iron suddenly isn't...

Low speeds are the key for austenitic stainless (stuff like the typical 304/316) so that they never get hot enough to harden on cooling under the drill. They pick up really badly when thread cutting or justing running on a nut that encounters a burr too - feel any resistance building and back off - don't try to push it. Clean the thread, get rid of burrs and make sure there's lots of lubrication. There are some e.g. ferritic grades (one brand is Cromweld 3CR12) that drill and machine easily (much like mild steel) and still give some corrosion resistance - and still weld easily.

[Keith Hankins]

This is the second post I have seen this discussion. I buy Fisch drill bits. They are made in Austria/Germany and are of exceptional quality. Their forstner wave bits are the best out there IMHO

I have a set of those I've had for years, I still reach for them first!

[peter gagliardi]

WL Fuller in Rhode Island- small family run firm. Excellent products!

[ian maybury]

Posted it before, but Dieter Schmid Tools in Berlin tend to do a range of premium (and some budget - so check out the descriptions) drilling products - suff like Colt, Famag, Fisch and Star-M from Japan. Even if it's not economical to order from him its a good place to check out what the good (Euro inclined) stuff is: http://www.fine-tools.com/bohr.html

I have a set of the Star-M hinge drills - they are really nicely made. Not cheap… PS added later - the ones from a Japanese supplier on EBay look OK, but there's some cheaper Taiwanese made one branded Star M on the bottom of the linked page - don't know anything about those...

[John Coloccia]

Drilling a wide variety of sizes in a wide variety of materials can be challenging.

Some misc items off my desk from projects we've done.

What is the item sitting in the hole in the bolt?


309518

Looks like a pin from a connector.

Before blaming the bit, I'd check and see if the quill has play.

[Greg R Bradley]

Looks like a pin from a connector.

How would you like to drill the hole for that tap.
Here is another picture of that tap against the gap in the lockwasher.
309525

[John Coloccia]

How would you like to drill the hole for that tap.
Here is another picture of that tap against the gap in the lockwasher.
309525

I've drilled holes for .050 screws/taps (wish I could remember the actual size, but that's pretty close, I think...0-80, maybe?)...and the answer to your question is I don't want to do it again, and I broke a LOT of bits!

[Peter Kelly]

Posted it before, but Dieter Schmid Tools in Berlin tend to do a range of premium (and some budget - so check out the descriptions) drilling products - suff like Colt, Famag, Fisch and Star-M from Japan. Even if it's not economical to order from him its a good place to check out what the good (Euro inclined) stuff is: http://www.fine-tools.com/bohr.html

I have a set of the Star-M hinge drills - they are really nicely made. Not cheap...FYI-the Star-M drill bits are also available on Ebay. There's a seller on there that ships directly from Japan which might be a little cheaper if you're ordering from the US.

[Greg R Bradley]

I've drilled holes for .050 screws/taps (wish I could remember the actual size, but that's pretty close, I think...0-80, maybe?)...and the answer to your question is I don't want to do it again, and I broke a LOT of bits!
If you were using a 0.050" (3/64") drill, it would be for 0-80 that fits in a 0.060" hole. 80 threads per inch.

That one uses a 0.0089" drill and has 318 threads per inch. If it went through a hole with clearance, the hole would be 0.0118".

[John Coloccia]

If you were using a 0.050" (3/64") drill, it would be for 0-80 that fits in a 0.060" hole. 80 threads per inch.

That one uses a 0.0089" drill and has 318 threads per inch. If it went through a hole with clearance, the hole would be 0.0118".

Some sort of lubrication channel?

[Evan Patton]

I just picked up 2 sets of Bosch TiN coated bits after being disgusted too many times with my 5 incomplete dull sets. I really like them so far.