Drill bits - what do you buy ?

[theoldwizard1]

I'm just a DIY guy. I don't have the time or the talent to sharpen drill bits. 1/8" and 1/4" are "disposable". When you into Silver and Deming bits ( >1/2") they are getting pricey !

So I need to enlarge a 1/2" hole to 5/8" in a 1" thick piece of steel. Shouldn't be a problem, right ? Brand new (Chinese) black oxide S&D bit. About 1/2 way through it just stopped cutting !. I was trying to use a slow speed and not excessive pressure, but the bit is DEAD !

Drill Hog sells M7 "Hi-Molybdenum" bits and M42 "Cobalt" bits. They also come with a lifetime warranty.

So are the M42 bits worth the extra money ?

 

[jfleisher]

Norseman.

 

[PBCampbell]

Doesn't exactly answer the question, lol.
Do you have any idea what the material is besides steel? Is it part of a manufactured assembly or just a hunk? Someone may be able to guess at the alloy with more info. Of course if the price difference isn't much go with the m42.

 

[Dave455]

Sadly, the most important thing with drill bits remains the manufacturer.

I’d take a drill bit from a decent manufacturer in HSS, in preference to a “Made in China” bit, in some supposedly exotic material, any day.

Yes, basically, for small bits you’re best to treat them as disposable. I get TiN coated for this purpose, in my case up to 1/8” ish.

For bigger drills, in softer steels, you’re best off sticking with HSS and having a go a sharpening them when needed, provided the hole isn’t too big or too deep. A 5/8“ hole an inch deep is both.

Cobalt is ideal when you need something resistant to higher temperatures, so it’s probably what I’d use in this case. Yes, they are worth the money. The hole you’re drilling is still probably about the limit for a conventional drill bit though.

Are you using a drilling machine or a hand held drill? If a drilling machine try and get some coolant. Keep the speed down but maintain the downforce to keep the bit cutting. You want to see continuous swarf.

If handheld then you are totally on the limit (I’ve done it) but would be better off with a magnetic drill and rotabroach (assuming it’s a through hole).


If the steel is anything other than softish mild then you will need a specialist drill bit.

There is good free advice from firms such as MSC.

 

[Mgdoug3]

I buy USA made drill bits usually in mechanic or machine screw length. I especially like machine screw bits on my mill because I don't have to move my table as much when switching operations. Machine screw bits are so much more sturdy if you have to use a hand held drill.

 

[2ndGearRubber]

I buy USA made drill bits usually in mechanic or machine screw length. I especially like machine screw bits on my mill because I don't have to move my table as much when switching operations. Machine screw bits are so much more sturdy if you have to use a hand held drill.

Yup, I just buy USA made stuff. My only exception is the astro turbo bits with the step bit points. Typically for singles and filling indexes that have run low I buy norseman at HJE. For specialty stuff like left hand stubbies I buy singles from snap on who is surprisingly competitive.


Enlarging a hole from 1/2 to 5/8 in a 1" thick piece of steel is nuts. You're cutting all with the flutes, not the center of the bit. For a thinner material I'd say use a step bit. For that thickness, no "regular" drill bit is going to work well, even in a drill press. I'd be looking to hog it out with a carbide burr if you can deal with a very sloppy fit. You could try a 1" step bit, but that's going to struggle immensely. I'd buy some quality cutting oil. LOL

 

[MJD1]

Ship and car reamer is best for that application. Not cheap but the best option. With that being said if this is a one off thing I'd use a S&D bit with good cutting fluid

 

[GeoBruin]

That's a big hole in thick material. I would normally recommend an annular cutter as mentioned above, but it's hard to center an annular cutter with an existing hole unless your using a mill and an edge finder.

If I were trying to do exactly what you're doing with the tools on hand, I would use a Norseman step reamer to enlarge the hole to a depth of 1/2", then flip the part and enlarge it from the other side to 1/2".

HSS Step Reamer Gold Oxide | Norseman™ Drill and Tool

Norseman™ Drill & Tool - Step Reamer low temperature stress relief that enhances lubricity, reduces friction and increases toughness.

www.norsemandrill.com

 

[MarineScott]

I too prefer USA made bits, but I must say, some of the Chinese double ended 1/8 inch bits are well worth it and sharpen nicely. I use these a lot for pilot holes.

 

[jfleisher]

Norseman.

I answered the question in the subject of his post… lol

 

[RoninB4]

-Going from 1/2 to 5/8 in a 1" thick steel plate is very doable, even with less than premium drills. No mention of what powers the drilling, this is important too. No mention of the speed involved but if the drill flutes "disappear" then it's way too fast. No mention of the color of the chips being produced at the start. If they weren't silver then your RPM is too fast. If they were yellow, purple, or blue then you were going WAY too fast. No mention of cutting oil or coolant either, this makes a very big difference. No mention of continuous drilling or whether you did an interrupted cut (peck cycle). Continuous drilling generates a lot of heat, especially when you're drilling at a depth of approaching 2X the drill diameter. The quality of the drill bit itself is quite important but your RPM, technique, and machine are also important.

There's a chance you've already work-hardened the material if the drill "just stopped cutting". The material may be steel but there are plenty of flavors in steel, some being more difficult to cut than others. There's also plenty of examples of plate steel being a mix of different types of steel melted down to make new plate, not uncommon if it came from overseas. I've even known/seen of instances where armor plating from battleships may have been used. Steel is NOT all the same.

I've mentioned a few things to do about speed, cutting fluid, and technique. These are not options when plate thickness is 1", do them. I'm also going to suggest drilling from the other side to meet half-way. This makes it easier on the drill, less heat generated, and avoids the possibility of an already work hardened surface you may have created.

I'm also going to suggest you learn to sharpen a drill. Don't have the time to do it? Seems like you have all the time in the world right now if the job isn't getting done. Don't have the talent? Learn to do it. It's not that difficult and all of us started at the same point as you. A few video's should do. In this instance you only have to concern yourself with a small amount of clearance behind the cutting edge, just duplicate the existing angles a bit at a time before flipping to the other side. Go gently so you don't overheat the drill, keep a can of coolant/water nearby to prevent overheating. If the drill is getting too hot to hold plunge it into water until it ok to hold again. About .012 off per side will likely be good enough.

If you want to spend your money on expensive cutting tools just to throw them away that's your personal choice.

 

[HamAndEggs]

I forever buy DeWalt. They got the top rating on Project Farm, and their warranty is solid. They have me for life after that

DeWalt Drill Bit Snapped - Warranty

About a year ago I got a set of DeWalt drill bits after project farm rated them the best, and they were on sale at HD When I was working on my trailer, the hardly used 5/16 bit just snapped right in two when I was drilling through some metal. It was in reverse and I was getting it out of the...

www.garagejournal.com

 

[uart]

When you into Silver and Deming bits ( >1/2") they are getting pricey !

Yeah larger sizes get fairly pricey, especially with ones with better quality and better materials. The cheap Chinese one you got is probably roll forged 4241, which is barely even HSS (about half the total Tungsten and Molybdenum as most HSS). Even so, it should still cut mild steel ok.

So I need to enlarge a 1/2" hole to 5/8" in a 1" thick piece of steel. Shouldn't be a problem, right ? Brand new (Chinese) black oxide S&D bit. About 1/2 way through it just stopped cutting !. I was trying to use a slow speed and not excessive pressure, but the bit is DEAD

Should be doable. Can you post any pictures of the drill bit (tip) and the work piece?

It might just be that the bit has lost its edge on the extremities (near the lands) and could be a good time to have a go at learning to sharpen. You've only got to get a half decent cutting lip on the outer 1/16th to get cutting again in that hole. It doesn't really matter if you don't get a nice clean facet along the whole lip or if you munt the chisel point, just getting an outer edge with some ok clearance angle should get you cutting again.

 

[toolenthusiast]

Don't have the time to do it? Seems like you have all the time in the world right now if the job isn't getting done.

You’ve got “management” written all over you

…and that’s not insult; I’m a manager myself

 

[RoninB4]

You’ve got “management” written all over you

…and that’s not insult; I’m a manager myself

-Nope. Not even close. I was a tool and die maker for 20+ years. No prior background, family history, or even a formal apprenticeship to learn from. Largely self taught (Machinery's Handbook 20th edition) and learned from grumpy old men in the shops. Certified as journeyman after many years in the trenches. Formal education, pre-med drop out (ran out of money) and all the CAD classes that were available 25 years after dropping out of college. I refused to give up and admit I couldn't do something.

If a dummy like me can learn so can just about anybody.

 

[545_days]

I have had good luck with buydrillbits.com
They have both US made and foreign bits and their website makes clear which you are buying.

Edit to add: I have purchased US made, I can't comment on their foreign bits.

 

[rockettauto]

A reamer is the proper way to enlarge a hole. If you don't need to do it often a cheap one will be fine.

https://www.amazon.com/dp/B0BCVPZ9Z9/?tag=atomicindus08-20

 

[Buckaroo5]

I have a set of HSS Drill Hog bits I bought several years ago. I have seen a number of posts that said they could not get in touch with them regarding the "lifetime warranty". The discussion was that the metal drill bit case manufactured by Huot says made in the USA and I believe that to be true. The bits inside provided by Drill Hog are the question. There was discussion that the bits were sourced from China. The card inside the case says Drill Hog USA, but it does not say the bits are manufactured in the USA. I am concerned this may not be legit. I have gotten recent emails from a person that says he is the Drill Hog guy with things for sale - I am steering clear. Really I am not overly concerned about China vs USA sourcing as the long as the quality is there - it is the failure on the warranty coverage and the potential subterfuge that concerned me.

 

[isb cornbinder]

I prefer Cleveland and their other companies for twist drills. I purchased twist drills made in Switzerland and they were excellent, but expansive.
The only taps I buy are YAMAWA from Japan.

 

[RoninB4]

A reamer is the proper way to enlarge a hole.

-Proper way? You're entitled to use whatever method you feel works for you but using a tapered reamer is NOT the proper way in a 1" thick plate of steel. Try it sometime, you'll find out why. Not trying to be insulting, please excuse me if it reads that way.

 

[rockettauto]

-Proper way? You're entitled to use whatever method you feel works for you but using a tapered reamer is NOT the proper way in a 1" thick plate of steel. Try it sometime, you'll find out why. Not trying to be insulting, please excuse me if it reads that way.

Lol, that's a bridge reamer and thick steel plate is exactly what it's designed for. Thick plate, in particular over 20mm in thickness is the perfect application for a bridge reamer. Though you may want to use an impact driver at that thickness if you plan to do more than one or two.

Though many get by with doing it, regular two flute twist drill bits are not intended for enlarging holes.

 

[RoninB4]

Lol, that's a bridge reamer and thick steel plate is exactly what it's designed for. Thick plate, in particular over 20mm in thickness is the perfect application for a bridge reamer. Though you may want to use an impact driver at that thickness if you plan to do more than one or two.

Though many get by with doing it, regular two flute twist drill bits are not intended for enlarging holes.

-I guess that depends upon where the metal removal is happening and what is powering the drill. Never worked on a bridge so maybe I need to back off my claim. By the same token nobody in a machine shop would use a reamer for that purpose, 2 flute (even 4 flute) twist drills are used every day to enlarge a hole so are spade drills. Tapered reamers are for taper pins, machine shops don't even carry tapered reamers that large for a reason. Bridge builders use what works for them, so do machine shops.

Can we agree that we're both wrong and right? I appreciate you educating me on bridge building.

 

[rockettauto]

-I guess that depends upon where the metal removal is happening and what is powering the drill. Never worked on a bridge so maybe I need to back off my claim. By the same token nobody in a machine shop would use a reamer for that purpose, 2 flute (even 4 flute) twist drills are used every day to enlarge a hole so are spade drills. Tapered reamers are for taper pins, machine shops don't even carry tapered reamers that large for a reason. Bridge builders use what works for them, so do machine shops.

Can we agree that we're both wrong and right? I appreciate you educating me on bridge building.

Well, of course. You can do things a lot differently if you're using something rigid, with a controlled feed and speed.

In a shop I think a core drill would be better. In practice, yeah, on a machine, happens all the time, but the processes are usually designed to avoid it.

In the field, with hand tools...I'd follow this mostly.

Enlarging Existing Holes

Enlarging Existing Holes

www.cutting-tool-supply.com

With the exception of those bridge or car reamers.

They're kind of crude, but not as crude as the result of a twist drill trying to go 25 percent larger by hand. They definitely make an easy job out of plate by comparison.

Anyway I get where you're coming from if it were a standard tapered reamer or a pin reamer. First thing that would come to mind in a shop for me if I heard reamer is either some sort of taper, or finishing the last few thou of a hole.

 

[merkyworks]

Twist drill 1/32or1/64 smaller than desired hole size then follow with straight flute reamer at desired hole size.

 

[theoldwizard1]

Twist drill 1/32or1/64 smaller than desired hole size then follow with straight flute reamer at desired hole size.

What DIY person has reamers ?

 

[merkyworks]

it depends really…some DIY’s have mills and/or lathes along with lots of tooling. Some might have just some HF drill bits and hand drill. both exists and both are fine, I’m not shaming anyone either way, but yes I think some DIY’er might have or want to buy reamers.

 

[merkyworks]

A good single bit option would be Norseman Vortex bits, PN: 26073

 

[man-a-fre]

Norseman and Astro.

 

[shanker]

according to Amazon the Norseman & KnKut are both made in USA while the Astro's are imports.

Are the Norseman & KnKut's made by the same factory?

 

[rockettauto]

What DIY person has reamers ?

The ones enlarging 1/2" holes in 1" thick steel plate , that's usually a little beyond your average Lowe's shopper.

 

[merkyworks]

according to Amazon the Norseman & KnKut are both made in USA while the Astro's are imports.

Are the Norseman & KnKut's made by the same factory?

Been curious about the whole story on this as well.
From what I have gathered Astro owns the IP/patent on the design. Astro did an exclusivity deal with Matco some years back and they were made by US manufactures. That exclusivity deal has since ended. Astro now sell there design under there own name and having manufactured by a Taiwan company.

So how does Norseman/KnKut fit in?
**100% speculation I have nothing to back this up**
My guess is Norseman/KnKut was the US manufacture making the Astro licensed bits for Matco but since the exclusivity deal is over they are also selling them under their own names/brand. From a post I read here and reading between the lines there might be a legal issue between who own the IP and who is selling bits.

 

[shanker]

Been curious about the whole story on this as well.
From what I have gathered Astro owns the IP/patent on the design. Astro did an exclusivity deal with Matco some years back and they were made by US manufactures. That exclusivity deal has since ended. Astro now sell there design under there own name and having manufactured by a Taiwan company.

So how does Norseman/KnKut fit in?
**100% speculation I have nothing to back this up**
My guess is Norseman/KnKut was the US manufacture making the Astro licensed bits for Matco but since the exclusivity deal is over they are also selling them under their own names/brand. From a post I read here and reading between the lines there might be a legal issue between who own the IP and who is selling bits.

I personally purchased the Norseman bit's as they were a few dollars cheaper (still more expensive than the Astro's) but couldn't find any data differentiating them from KnKut. I wanted the mechanic's length and only Norseman was in stock on Amazon at the time.

 

[Hytekrednek]

I mainly use KnKut and Cleveland . I love the stubby KnKuts

 

[Kuma601]

Whatever USA bits in cobalt 135 degree split points that Grainger has. Cle-line, Cleavland, Chicago-Latrobe, Westward (when they are USA,Japan or German origin.) Ive also used larger countersinks to enlarge holes that are not seen.

This was an interesting video:

 

[RTM]

What DIY person has reamers ?

Me, two or three sets, just cuz I found them at GS or ES, and a dozen or more loose ones, gotten with toolbox lots. Some tapered, but most parallel.

 

[WhataTool]

Been curious about the whole story on this as well.
From what I have gathered Astro owns the IP/patent on the design. Astro did an exclusivity deal with Matco some years back and they were made by US manufactures. That exclusivity deal has since ended. Astro now sell there design under there own name and having manufactured by a Taiwan company.

So how does Norseman/KnKut fit in?
**100% speculation I have nothing to back this up**
My guess is Norseman/KnKut was the US manufacture making the Astro licensed bits for Matco but since the exclusivity deal is over they are also selling them under their own names/brand. From a post I read here and reading between the lines there might be a legal issue between who own the IP and who is selling bits.

The Matco ones were always made overseas.
Astro has the original patent(s) and made them for matco now make 1 type under Astro.
Norseman copied the design because of all the sales and humb-ub it was drawing and started feeding a bunch of other brands, any that say made in US on them, and thus are being sued for copying a patented design. usually it's the other way around, an import copying a US design. But it's a new age these days I guess, and money is money.

 

[CR888]

We're a funny bunch, this is an LOT of advice to drill one hole. Hang on we're not even doing that. Get a semi decent HSS name brand bit and go for it.

 

[uart]

We're a funny bunch, this is an LOT of advice to drill one hole. Hang on we're not even doing that. Get a semi decent HSS name brand bit and go for it.

There's just not enough info been given by the OP, so we're all making assumptions. Is he using a hand held drill? Does he have access to drill from either side? Is it mild steel?

But I agree, unless it's some alloy that has work hardened then any half decent HSS drill bit should do it. He's made it half way with what sounds like a cheap nasty drill bit, so any decent bit should be able to finish it off.

Certainly to expand a 1/2 hole to 5/8 in mild steel is trivial on a drill press. I've done it before, and even on my $99 bargain basement Chinese DP (12 spd) it was trivial. Plain HSS drill bit, nothing special, and no it didn't chip or break or even get particularly dull.

 

[dogdog]

If you know that this is for diy probably not used in precision hole drilling and you would used certain size more like 1/8 1/4 1/16 etc why not just buy the job lot packs. They used to sell these in homedepot / Lowe’s, now have not seen them. Maybe Amazon? Something like these.

As far as coated bits, it’s going to be a guess they can be very good quality hss under that coating or crappy like the cheaper HF ones, will still drill holes fine in most materials.

Before some one jumps the gun to say it’s not accurate….. that person probably never know why they invented reamers.




GMTOOLS 230 Pcs Drill Bit Set, 135° Tip Titanium Coated High Speed Steel, Twist Drill Bit Kit for Iron, Aluminum Alloy, Copper, Wood, Plastic, with Hard Storage 1/16"-3/8" https://www.amazon.com/dp/B0BG5NQ2LQ/?tag=atomicindus08-20

 

[Dakotadadv8]

Got to Lowes or Home Depot and buy the best.