# Serious drill bit purchase help!



## GunsOfNavarone (Feb 28, 2020)

So I am new to machining...a couple years. I guess I always took drill bits for granted...and to me, Dewalts were great. Much has changed in the last couple years. I needed metric, the 135 degree, some stubbies, misc center drill mills...it's just getting crazy. Letter size, wire size, screw machine, jobber...How many damn kind of drill bits are there (rhetorical) Today I needed a 5.75mm....found a (I think it was a 15/64?) Dewalt, stuck in in my mill and I can't even call it run out....it was just....bent? Dear lord! It's wobble was probably a mm! 
This brings me to my next purchase and I could use some direction. I want "drill bits" I can use on MILL and LATHE. I want a full set (like 115 piece or more) I don't want junk (I like Drill Hog and Norseman, but I'm sure there are MANY I am unaware of.) I realize there will be one offs I still need in the future, I just felt dead end today even with the 100+ drill bits I have. I mostly work with mild steel and (machining) stainless. I'd LIKE to keep it under $300, bit there is wiggle room.
I appreciate your guys' wealth of knowledge, that's why I'm here.


----------



## benmychree (Feb 28, 2020)

Good ain't cheap, cheap ain't good.


----------



## GunsOfNavarone (Feb 28, 2020)

Yup, yup... I get that. I'm a firm believer.


----------



## vocatexas (Feb 28, 2020)

A drill bit is not for drilling precision holes. If precision is needed, you drill slightly undersize, then use a reamer to get the hole to final dimension. Yeah, MORE tooling to buy! Let's see...there are straight reamers, spiral reamers, tapered reamers, adjustable reamers...


----------



## GunsOfNavarone (Feb 28, 2020)

I really don't work within the tolerance where I'll need to undersize/ream. Just want a set that can handle the task at hand. I have a Black Oxide set from Dewalt that are MUCH straighter than the large "gold" Dewalt set.
I'm looking at these...
DrillHog Cobalt


----------



## Aukai (Feb 28, 2020)

I use drill hog for hand drilling, Chicago Latrobe, and Norseman for the machines. That's my setup.


----------



## JimDawson (Feb 28, 2020)

I like like the Harbor Freight cobalt sets.  I have several sets for utility uses, get them with the 20 or 25% off coupon.  When I need speciality bits, I go to Amazon or my local tool supply depending on who has what when I need it.  I buy pretty much all 135 degree cobalt, with a few solid carbide thrown in when needed.


----------



## GunsOfNavarone (Feb 28, 2020)

@JimDawson With seeing the lack of trueness of my dewalts, I'm so leary to not go high(er) end. I know I want 135 degree, screw machine or stub length. Cobalt or M7. A set that covers fractional, metric, wire and or letter size. I THINK these maybe best for me unless I'm pointed in another direction. Chicago-Latrobe draws me in. If I buy each of there sets (of the different sizing systems) I could get out for $300 to $350. Other than some one offs, I want this to be the "last time" I need to buy compete sets of bits. I was just so shocked by what I saw in what I believe to be quality, and I suppose for their intended use, they're fine. I'll' have to post a video for kicks.


----------



## mikey (Feb 29, 2020)

I think you're going to find that a 115 piece, 135 degree split point cobalt screw machine drill set is going to cost you a good bit more than $350.00. Sorry but you are looking at a premium set here. Prices get lower if you go with a 118 degree point in HSS, which is not a bad compromise that will get you within your target price range. 

Good brands to consider: PTD, Triumph, Cleveland, Chicago-Latrobe. I own all of these and they are very good. My screw machine set is a 115 piece stub length 118 degree and it works fine for me. 

Cobalt is fine for those drills you use most often in stainless steel but you don't need the entire set to be cobalt. Maybe get a decent set in HSS and buy cobalt drills in the sizes you need.


----------



## mattthemuppet2 (Feb 29, 2020)

get a 29pc 1/16-1/2" machinist (mechanics?) length set first, that'll do most stuff. Then if you drill'n'tap small holes a stub/screw length 0-60 set will do the trick. Then if you drill'n'tap larger holes, maybe a stub/screw length letter set would do the trick. I use my 29pc set and number set the most as the majority of my work is small, but the letter set does come in handy every so often. I also have a jobbers length 115pc set that I use occasionally when I have deeper holes to drill, though I always start them with the shorter drill.


----------



## projectnut (Feb 29, 2020)

First question is what materials do you most commonly use.  If aluminum is your primary material I would suggest parabolic drills, if steel is the most common I would use standard twist drills.  As for brands I would add Precision, Viking, and YG to Mikey's list.  YG is a fairly new player out of South Korea.  They have plants in several countries.  If considering this brand I would look for those made in the US of South Korea.  Viking is the parent company that makes Triumph.  I believe Norseman is their "economy" brand.

There are several more high end German and Austrian brands, but I'm not sure they would be worth the money outside a high production professional shop.


----------



## ddickey (Feb 29, 2020)

Along with Norseman I have a lot of RedLine Tools drill bits (stub length). They're very good also. Pretty sure they're made in the US.


----------



## GunsOfNavarone (Feb 29, 2020)

mikey said:


> I think you're going to find that a 115 piece, 135 degree split point cobalt screw machine drill set is going to cost you a good bit more than $350.00. Sorry but you are looking at a premium set here. Prices get lower if you go with a 118 degree point in HSS, which is not a bad compromise that will get you within your target price range.
> 
> Good brands to consider: PTD, Triumph, Cleveland, Chicago-Latrobe. I own all of these and they are very good. My screw machine set is a 115 piece stub length 118 degree and it works fine for me.
> 
> Cobalt is fine for those drills you use most often in stainless steel but you don't need the entire set to be cobalt. Maybe get a decent set in HSS and buy cobalt drills in the sizes you need.


Weird...on Amazon, $186 for one set (I think letter) and $90 for the other (fractional)they are cobalt...don't know if they are "premium" but I'm not a premium kind of guy. I agree about the HSS, but I'd rather do this "once". The machining rabbit hole is VERY deep....isn't it fellas?


----------



## projectnut (Feb 29, 2020)

The price for the letter drills seems a bit excessive.  Last November I purchased a new  set of Greenfield parabolic letter drills in a Huot index on eBay for $69.00.  There are several eBay vendors with quality drills.  Just be sure to check the prices against reputable industrial suppliers.  I've seen prices range from nearly double the standard retail price to less than 25% of retail.

I often checkout businesses that buy out businesses, or surplus dealers.  They generally have the best prices and often include "best offers".  They rely on quick turn around and volume sales rather than holding out for top dollar.


----------



## GunsOfNavarone (Feb 29, 2020)

Funny...one person says the $300-$350 for the set I'm looking at sounds way under priced, another says it sound excessive.   There is a part of me that wants to Accusize (I have had great luck with their products) but I feel like  got to get a large step up on drill bits.
There is a beginning step for me learning this ridiculously complicated world of making a hole in a piece of metal. At least I know I want/need certain things. I appreciate the brand names you guys are throwing my way...these are all foreign to me and would never know to look them up. I really need/want to have this done and ordered by end of weekend. I will expand to add reamers though I feel the need will be limited. I have a dozen or so straight reamers from a very successful machinist that retired here in Colorado....I've never needed to use them.


----------



## projectnut (Feb 29, 2020)

Price point is a matter of perspective.  Some people think a $100,000.00 car is excessive, and over the top.  Others think it's the bottom line as to where mass production yields to quality.
I think you're going to find prices for the same product all over the map.  I've found the more expensive retailers don't necessarily carry any higher quality tools.  MSC for instance generally charges premium prices for the same brands you can purchase elsewhere 25% to50% cheaper.

I generally go with name brands I've used over the years that have proven to be high enough quality they don't have to be replaced on a regular basis.  I shy away from HF for anything that I intend to use for more than a specific job.  I've had some good quality tools from them, but far more often they aren't the quality that will last for years to come.

If money is a concern at this point I would buy a fractional or metric set of drills up to 1/2" (by 1/64") or 13mm.  They are the ones you will use far and away more than any other sizes.  I have drills up to 1" but find those over 1/2" get used less than 10% of the time.  At this point if you need larger drills I would buy name brand ones specifically for the job at hand.  As time and budget allows you can fill in the blanks. 

Here's a complete set (fractional, wire, & number) that may be of interest

Cle-line is made by Cleveland Twist Drill








						Cle-Line C21126, 1/16" to 1/2", 115 Pc, Fractional, Letter & Wire Drill Bit Set  | eBay
					

P/N C21126. Fractional - 1/16" to 1/2". 115 Jobber Length Bits. Wire - #60 to #1. Letter - A to Z. Min Bit Size - 0.0400". Max Bit Size - 1/2". Point Angle - 118°.



					www.ebay.com
				




Here's one with just fractional drills








						Cle-Line Jobber Drill Set 21 PC HSS 118 Deg C21114 for sale online | eBay
					

Find many great new & used options and get the best deals for Cle-Line Jobber Drill Set 21 PC HSS 118 Deg C21114 at the best online prices at eBay! Free shipping for many products!



					www.ebay.com
				




Here are some fractional parabolics








						Cle-Line Jobber Drill Set 21 PC HSS 118 Deg C21114 for sale online | eBay
					

Find many great new & used options and get the best deals for Cle-Line Jobber Drill Set 21 PC HSS 118 Deg C21114 at the best online prices at eBay! Free shipping for many products!



					www.ebay.com
				




Here are some 118* metrics








						Cle-Line Jobber Dril Set 25 PC Metric HSS 118 Deg C21131 for sale online | eBay
					

Find many great new & used options and get the best deals for Cle-Line Jobber Dril Set 25 PC Metric HSS 118 Deg C21131 at the best online prices at eBay! Free shipping for many products!



					www.ebay.com


----------



## Winegrower (Feb 29, 2020)

About a year ago I bought a full set of Drill Hog, numbers, letters, fractions and reduced shank up to 1”.   I have not had a problem that I would blame on a drill, and the set is still intact, no replacements necessary to date.   It ran about $300 from eBay as I recall.   I’m satisfied, would do it again.


----------



## 7milesup (Feb 29, 2020)

Excellent thread.

GunsofNavoron... I am facing the same issue as you.  I purchased a set of Drill Hogs (HSS) and quite frankly, they are borderline worthless in my opinion.  They have this return policy that is a pain.  You have to save up your broken bits and send them to the guy, and he will return them.  I bought a set of cobalt drills from Menards that have been really good.  Problem is that they limited to only cardinal sizes up to 3/8"

I will be checking out the ones that ProjectNut just posted.

LOL... Winegrower was typing while I was posting.  Two different people with two different Drill Hog results.


----------



## rwm (Feb 29, 2020)

My approach is a little different (and maybe incorrect so I will follow this thread.) I have never been happy with resharpened drills, either by hand or with Drill Doctor. I treat my drills as disposable. I have been buying Irwin brand cobalt drills in multi-packs and just replacing them when they get dull. For me, there are several sizes that I use a lot of and the other sizes last a long time due to limited use. I think cobalt is essential for long drill life and I do drill a lot of stainless. Appropriate use of lubricant or coolant will also help tremendously.
Robert


----------



## projectnut (Feb 29, 2020)

Winegrower said:


> About a year ago I bought a full set of Drill Hog, numbers, letters, fractions and reduced shank up to 1”.   I have not had a problem that I would blame on a drill, and the set is still intact, no replacements necessary to date.   It ran about $300 from eBay as I recall.   I’m satisfied, would do it again.





7milesup said:


> Excellent thread.
> 
> GunsofNavoron... I am facing the same issue as you.  I purchased a set of Drill Hogs (HSS) and quite frankly, they are borderline worthless in my opinion.  They have this return policy that is a pain.  You have to save up your broken bits and send them to the guy, and he will return them.  I bought a set of cobalt drills from Menards that have been really good.  Problem is that they limited to only cardinal sizes up to 3/8"
> 
> ...


 There was a thread about Drill Hog a while ago.  As it turns out it's a company registered in the Canary Islands doing business from California and Montana.  They are essentially a broker buying drills from many manufacturers, both in this country and from abroad.  I've seen just about a 50/50 spread of good and bad reviews.  The point being you may get high quality drills, or you may not.  It all depends on what they're buying at the time.

As for sharpening I had reasonable results from my Drill Doctor for several years.  Eventually it wore beyond what I was willing to put up with.  I happened across a Black Diamond drill grinder and it's done an excellent job.  However in most cases a Black Diamond is beyond reach of most hobbyists.  New they're in the $8,000.00 to $10,000.00 range.  I happened across  a like new one at a price not much more than a Drill Doctor.


----------



## GunsOfNavarone (Feb 29, 2020)

Drill Hog reviews run similar...some say junk, some say greatest thing ever. I would far more respect the opinions here...you never know whats a real review anymore (a fair amount of Amazon reviews are fake)
I personally want on the shorter side bits....no jobbers for me. I want them to center well, so 135 degree, I do want/need either cobalt or Moly. I'm just going to research a bunch of the brands here I had never heard about before and hop on one. I probably will buy 2-3 smaller sets instead of the 115 piece out the gate. Its not so much for the upfront cost as I probably only need LETTER OR WIRE SIZE...not both. Of course I need fractions and metric.


----------



## RJSakowski (Feb 29, 2020)

GunsOfNavarone said:


> Its not so much for the upfront cost as I probably only need LETTER OR WIRE SIZE...not both. Of course I need fractions and metric.



Wire size only goes to .228".  You will need letter size or fractional after that.  A metric set 1 - 13mm by .1mm would be a nice addition.  You will be .002" away from your desired hole size at worst.


----------



## Aukai (Feb 29, 2020)

The machining rabbit hole is VERY deep....isn't it fellas? 

Only if you look back to see how far you've gone....


----------



## GunsOfNavarone (Feb 29, 2020)

Someone (actually multiple people) warned me when I decided to add a mill & lathe to my shop, that I would spend more on tooling that the actual machine. I took that with a grain of salt, but they were sort of wrong. I am trying to control the spending and I bet I have surpassed it, but easily could multi-fold the initial cost. Alright, they were not wrong....but I don't think there warning were strong enough!
I know there is a reality as well, what make sense to some (i.g. drill hole undersized and ream to desired size) is someone else's reality. That's where I have made some mistakes. I need to understand what my reality is & move towards that. My problem is, I don't know what I don't know. Its on me to get recommendations AND do the online reading up. I have hours researching drill bits....DRILL BITS FOR GOD'S SAKE!


----------



## mikey (Feb 29, 2020)

I've been in this hobby for a very long time and have drilled, reamed and bored in most materials a hobby guy is likely to encounter. In all this time, HSS drills in 118 degree points have served me well. I have, but rarely use, my cobalt drills and since I tend to center punch or spot drill my holes, I don't have a strong need for 135 degree drills (although I own them). I drill stainless often and a sharp HSS drill handles it fine; it is more about speeds/feeds, lubricant and technique than the drill material.

Do not think that a cobalt drill will drill all holes successfully without a brain in YOUR head. Cobalt merely handles higher temps better than M2, that's all. You still have to use the right speeds and feeds. Also, there are times when screw machine drills are the ticket and times when jobber drills are needed; I have both and need and use both. If I had to pick only one length, I would get jobber drills because there are times when you need to go deep and screw machine drills just won't get it. Screw machine drills are more rigid, true, but they are not a panacea.

My advice is to buy drills in fractional, wire, letter and metric, in that order. I would buy them from reputable makers only and I would buy them in the point geometry you prefer; both 118 and 135 works. I would also buy some cobalt spot drills to suit the geometry of your drills. You can opt for cobalt if you choose but for probably 90% of the work you are likely to do, HSS will be fine. 

Learn to sharpen your drills. Doesn't matter what you use to sharpen them as long as they are sharp. 

Don't spend big money on reamers unless you are doing work that requires them frequently. They are expensive and for occasional use, buy the ones you need or learn to bore accurately. The wabbit hole is deep indeed, but this is one place where you can avoid some cost.


----------



## GunsOfNavarone (Mar 2, 2020)

If you guys had the choice between m7 cryrogenically treated steel or m42..which would you go with? I am down to Norseman and these 2 choices. Seems to be advantages to both, I would lean towards Cobalt M42, but the cryro is something new to me...buy they are still moly just hardened differently.


----------



## mikey (Mar 3, 2020)

Tough choice. Supposedly, cryogenic treatment is supposed to double the life of the drill as opposed to cobalt that can handle higher temps. If I was spending your money, I might chance the cryogenic bits.


----------



## projectnut (Mar 3, 2020)

To me the decision would be based on price.  If the cryogenic ones are only slightly more expensive I might give them a try.  All my drills are either HSS or some percentage of cobalt.  The vast majority of them are going on 40 years old and there's still plenty of length left for sharpening.  The ones that get sharpened or broken most are those under 1/4".  Replacements are usually around $1.00 or less each so there's no big expense involved to replace them.  

I never kept track of which drills I sharpen most often, but I do know 90+% are under 1/2".  For a while I was sharpening 50+ drills a month.  Even then most didn't need more than a quick dust up to restore the cutting edge.  Now days the number needing sharpening is much smaller.  I may have slowed down a bit as to their use, but having a good sharpener makes them cut better and last longer.

In over 20 years I've only replaced a couple drills over 1/2".  Both were snapped trying to drill through welds.  I kept one, but it's now about an inch shorter than it started out.  If I run into welded areas that need to be drilled it's the go to drill.


----------



## GunsOfNavarone (Mar 3, 2020)

The cryo and the cobalt are essentially the same price. Damn..ok. I might just flip a coin...Head’s is cobalt...


----------



## rgray (Mar 3, 2020)

I'll vote cobalt. Had good luck with them.
Next need to through in some carbide, to continue on down that hole.


----------



## ericc (Mar 3, 2020)

I have been very happy with garage sale and ebay finds, especially in the name brands.  I can send you a couple to try if you would like.  But, most cheap drill bits are good enough these days, as long as you can keep them sharp.  Harbor Freight and Lowes have decent offerings.  Now, taps are another matter.  Cheap taps are much worse.


----------



## GunsOfNavarone (Mar 3, 2020)

Thanks @ericc i think I’m gonna order the Norseman 115pc cryogenically hardened set. I appreciate the offer however. I’m just so on the fence about cobalt vs the cryo HSS. I do A LOT of stainless...and yes taps are very challenging on SS. I need a good suggestion on those but I’ll do one offs as needed.


----------



## rgray (Mar 3, 2020)

I put no faith in cryo hardened bits. 
just going on experience with other cryo things.
Very interested in hearing how they perform. Hopefully good!!!


----------



## projectnut (Mar 3, 2020)

GunsOfNavarone said:


> Thanks @ericc i think I’m gonna order the Norseman 115pc cryogenically hardened set. I appreciate the offer however. I’m just so on the fence about cobalt vs the cryo HSS. I do A LOT of stainless...and yes taps are very challenging on SS. I need a good suggestion on those but I’ll do one offs as needed.



As an FYI I would guess that 60% of the time I use 316, or 417 stainless.  The next most used material is 6061 or 6057 aluminum.  The remainder is 1018 steel and various bits of tool steel with a little brass and cast iron thrown in.  I don't own a cryo drill that I am aware of, but have never had drilling problems.


----------



## JimDawson (Mar 3, 2020)

GunsOfNavarone said:


> Thanks @ericc i think I’m gonna order the Norseman 115pc cryogenically hardened set. I appreciate the offer however. I’m just so on the fence about cobalt vs the cryo HSS. I do A LOT of stainless...and yes taps are very challenging on SS. I need a good suggestion on those but I’ll do one offs as needed.



If you're doing primarily SS then cobalt is the correct answer, assuming you don't have the speed to effectively use carbide.  I stuffed in a new, good HSS bit into my lathe the other day because that was the first bit I grabbed.  It lasted about 6 parts in 304 SS.  Then I put in a cobalt bit, and it lasted the rest of the job, a couple hundred parts.  Both of these were 135° stub drills.  For tapping SS I normally use Guhring spiral flute taps, ran the whole job on one tap.


----------



## GunsOfNavarone (Mar 3, 2020)

I feel like I’m hearing Colbalt is perhaps a safer bet than the unknown of the cryo hardened HSS. That’s my gut feeling too. I’ve got both in my cart & need to pull the trigger. I guess cobalt it is!


----------



## rwm (Mar 8, 2020)

The thing I like about cobalt is that if you happen to get the drill a little overheated it is not immediately trashed.  I really like mine.
Robert


----------



## tq60 (Mar 9, 2020)

Why the big sets?

Find a good price on a decent large set for "general use".

But you will find that you usually only use certain ones more than others. 

For the few sizes that get used often buy the best you can afford for the need.

If you only drill one hole in 10 years of some odd size a lower quality may be fine but drilling many a day then it matters.

Spend wisely...

We have the hf large set and many estate sale finds that get us by.

It seems we only use maybe 5 different sizes for common tasks.

Sent from my SAMSUNG-SM-G930A using Tapatalk


----------



## GunsOfNavarone (Mar 9, 2020)

I really needed to have Cobalt for the stainless I do. I have many drill sets, but some are brad point, some are 118 degree...etc. I just wanted  to knock out the the miscellaneous chaos & have a good base set. (I did buy the Norseman 115 piece cobalt set) I feel like 99% of my needs are covered now. The 135 degree bits are much nicer, I never had these before.
Ultimately, for others looking for drill sets, there is some good advice in this thread now. Thank you all!


----------



## ACHiPo (Mar 26, 2020)

May be too late, but I just got this from Travers Tool:  115 pc Rushmore (US) jobber length drill set for $177.99 (normally $282.16)

*To activate deal of the day pricing, simply mention or enter promo code DEAL into your shopping cart.*









						RUSHMORE USA A3789-USA 1/16
					

Machine Shop SolutionsProblem: Managing a large collection of jobbers drills is an added hassle when preparing for jobs. Solution: A handy portable set offers a convenient metal index and drill collection for all your needs.Stay Organized with this Value Pack of 115 Piece Jobbers Length Twist...




					www.travers.com


----------



## GunsOfNavarone (Mar 26, 2020)

Yeah, I went with the Norseman 115 pc Colbalt set. Maybe other will pick up that sale, seems like a killer deal!
Thanks!


----------



## GunsOfNavarone (Apr 27, 2020)

So, here it is a month later... I used a 1/8" bit for a project for someone here, on aluminum. I used a 4mm on stainless for a job for work. Today I was drilling a size V (YES! The ones I never thought I'd use came in super handy!) 18mm deep through aluminum and about 1/2 through...CRACK...clunk, clunk, clunk.... I was pecking and clearing strings out the whole time- WD40 as lube. It actually snapped off the leading flutes! WTH?! All this research, not a super cheap set and ALUMINUM?? They are sending me a replacement, nice, but why did this happen? 
I know aluminum gets gummy, but I really couldn't have been more careful. Flooding with coolant is great, but it's a drill bit set, not end mills. The Aluminum wasn't even warm. Help me out here guys...any ideas what I did that cause the fatal failure?


----------



## jwmelvin (Apr 27, 2020)

I was drilling a piece of steel this weekend with my Norseman cobalt 135° (5/16” diameter) and chipped both cutting edges immediately upon entry. Wasn’t going fast (~80 SFM) but there was some mill scale on the bar. I figured it the mill scale was a bigger deal than I thought and resharpened the bit myself (losing the split point). I was disappointed in my fancy drill but though. Maybe I should call them; do I go through the company I bought them from?


----------



## extropic (Apr 27, 2020)

GunsOfNavarone said:


> So, here it is a month later... I used a 1/8" bit for a project for someone here, on aluminum. I used a 4mm on stainless for a job for work. Today I was drilling a size V (YES! The ones I never thought I'd use came in super handy!) 18mm deep through aluminum and about 1/2 through...CRACK...clunk, clunk, clunk.... I was pecking and clearing strings out the whole time- WD40 as lube. It actually snapped off the leading flutes! WTH?! All this research, not a super cheap set and ALUMINUM?? They are sending me a replacement, nice, but why did this happen?
> I know aluminum gets gummy, but I really couldn't have been more careful. Flooding with coolant is great, but it's a drill bit set, not end mills. The Aluminum wasn't even warm. Help me out here guys...any ideas what I did that cause the fatal failure?



You say "about 1/2 through" so not a matter of binding at break through.
If your feed wasn't excessive, I suggest you write it off to a fluke.


----------



## mikey (Apr 27, 2020)

jwmelvin said:


> I was drilling a piece of steel this weekend with my Norseman cobalt 135° (5/16” diameter) and chipped both cutting edges immediately upon entry. Wasn’t going fast (~80 SFM) but there was some mill scale on the bar. I figured it the mill scale was a bigger deal than I thought and resharpened the bit myself (losing the split point). I was disappointed in my fancy drill but though. Maybe I should call them; do I go through the company I bought them from?



Did you happen to spot drill first? If so, this should not have happened.

I would contact Norseman and ask to have the drill replaced. A cobalt drill in that size is not cheap.


----------



## GunsOfNavarone (Apr 27, 2020)

jwmelvin said:


> I was drilling a piece of steel this weekend with my Norseman cobalt 135° (5/16” diameter) and chipped both cutting edges immediately upon entry. Wasn’t going fast (~80 SFM) but there was some mill scale on the bar. I figured it the mill scale was a bigger deal than I thought and resharpened the bit myself (losing the split point). I was disappointed in my fancy drill but though. Maybe I should call them; do I go through the company I bought them from?


Concerning.....
I purchased from Amazon...wrote them a note there and they are sending a new one. Probably who you bought them trough 1st, if no luck, go direct?


----------



## GunsOfNavarone (Apr 27, 2020)

mikey said:


> Did you happen to spot drill first? If so, this should not have happened.
> 
> I would contact Norseman and ask to have the drill replaced. A cobalt drill in that size is not cheap.


The 2nd time I did spot drill (and used a Dewalt bit!), but to be honest, brand new 135* split point and cobalt on aluminum...didn't think it was necessary. 9mm deep at that point...I was about 170 rpm. Yeah, these aren't kryptonite...Next time I'm gonna swaddle the bit first and sing it "Hush Little Baby".


----------



## mikey (Apr 27, 2020)

Never had a drill bit 'splode on me before. Not sure what happened but I suspect you just had a defective bit.


----------



## jwmelvin (Apr 27, 2020)

mikey said:


> Did you happen to spot drill first? If so, this should not have happened.
> 
> I would contact Norseman and ask to have the drill replaced. A cobalt drill in that size is not cheap.



I did not spot drill because I didn’t care much about the location and the bit had a split point, which I understood to minimize walking. 

I’ll reach out to my vendor.

Edit: I looked back and they are M7, not cobalt.


----------



## mikey (Apr 27, 2020)

jwmelvin said:


> I did not spot drill because I didn’t care much about the location and the bit had a split point, which I understood to minimize walking.
> 
> I’ll reach out to my vendor.
> 
> Edit: I looked back and they are M7, not cobalt.



Still, that should not have happened.


----------



## brino (Apr 28, 2020)

GunsOfNavarone said:


> Help me out here guys...any ideas what I did that cause the fatal failure?



What's the combined run-out on the machine and chuck?
If it was sweeping a circle, I could see that......
-brino


----------



## GunsOfNavarone (Apr 28, 2020)

brino said:


> What's the combined run-out on the machine and chuck?
> If it was sweeping a circle, I could see that......
> -brino


I was using an collet directly in quill, it’s very little (at least, not enough to ‘splode a brand new, cobalt drill bit. It was cutting really smooth/easy up to that point. I think it’s like @mikey said...just a bad bit/fluke.


----------



## Janderso (Apr 28, 2020)

Aukai said:


> I use drill hog for hand drilling, Chicago Latrobe, and Norseman for the machines. That's my setup.


+ 1 on Norseman


----------



## Janderso (Apr 28, 2020)

mikey said:


> I've been in this hobby for a very long time and have drilled, reamed and bored in most materials a hobby guy is likely to encounter. In all this time, HSS drills in 118 degree points have served me well. I have, but rarely use, my cobalt drills and since I tend to center punch or spot drill my holes, I don't have a strong need for 135 degree drills (although I own them). I drill stainless often and a sharp HSS drill handles it fine; it is more about speeds/feeds, lubricant and technique than the drill material.
> 
> Do not think that a cobalt drill will drill all holes successfully without a brain in YOUR head. Cobalt merely handles higher temps better than M2, that's all. You still have to use the right speeds and feeds. Also, there are times when screw machine drills are the ticket and times when jobber drills are needed; I have both and need and use both. If I had to pick only one length, I would get jobber drills because there are times when you need to go deep and screw machine drills just won't get it. Screw machine drills are more rigid, true, but they are not a panacea.
> 
> ...


All good advise Mikey. You have been down this road before.
At work, we drill out a lot of broken bolts. You learn what works and what doesn’t.
What did John say, cheap is crap, crap is cheap.


----------



## jwmelvin (Apr 29, 2020)

mikey said:


> Still, that should not have happened.


Just to close the loop on my thread fork, ISC Supplies contacted Norseman for me and Norseman will be sending me a new 5/16" drill bit.


----------



## Janderso (Apr 29, 2020)

Don't forget to get a few quality left handed bits. They save the bacon on broken bolts/studs.


----------



## macardoso (Apr 29, 2020)

I want to add my experience. I bought a cheap ENCO branded 115 pc set some years back. maybe 5-10% were bad grinds or were bent. I've replaced the bad or heavily used bits over the years with quality 135 degree split point drills. Bet my set is still 60% the original cheap ones and they work fine. My total expense to do it this way is low and spread out.


----------



## GunsOfNavarone (Apr 29, 2020)

macardoso said:


> I want to add my experience. I bought a cheap ENCO branded 115 pc set some years back. maybe 5-10% were bad grinds or were bent. I've replaced the bad or heavily used bits over the years with quality 135 degree split point drills. Bet my set is still 60% the original cheap ones and they work fine. My total expense to do it this way is low and spread out.


I can appreciate that for sure, but I have MANY small sets of Craftsman and Dewalt, nothing at a level I would choose for true machining. I work so hard and so many hours, I wanted to "splurge" on a decent set. How I used it when it broke...well both my Craftsman and Dewalt would have been fine. I'm just accepting it as a fluke. I've used one or two on thick stainless with no issues. As I break these or more hopefully, dull them, I will go to that fancy french sounding company for the one offs. I do have a jig for sharpening bits, but just don't think they will be as good...but I'll practice, but practice runs probably won't be good enough to rely on.


----------



## PaulH (May 3, 2020)

While the subject of drills is on hand...I see a lot of what I assume is surplus from aviation, piloted core drills on Ebay. Some of these with a little grinding on the pilot would probably have a tendency to run a little truer in drilling out a .22 rimfire barrel to 5/16"  for a liner installation than a twist drill, right? I've only got a one-off job and don't want to spend the money for a gun drill, and I'm intimidated by making a homemade "D" drill although I have a bunch of OH-1 to experiment with. On this job, a rough interior finish is not a detriment, but drilling from both ends to the middle (24" oal) it would behoove me to try to meet in the middle within, say .040" concentric. Opinions?


----------



## GunsOfNavarone (May 3, 2020)

@PaulH I can't help with your question unfortunately, but I'm just curious, why even try to re-line the barrel? How much could it be for a new .22 barrel? Seems like a fair amount of work AND you need to come up with a bit to do it...no guarantees first attempt will even fly? If your just going into this for the experience whether it works or not...make that D drill...maybe you'll surprise yourself.
Good Luck Brother!


----------



## PaulH (May 4, 2020)

1904 Marlin octagon barrel family heirloom, a candidate for a reline if there ever was one. Exterior of barrel marked in beautiful fine script of another century and pure American pride in workmanship.
The making of the "D" drill is not as scary as the heat treating afterward. Eek.


----------



## GunsOfNavarone (May 4, 2020)

Ahhh... when I hear .22 I picture LR AR style. If it’s an heirloom, you gotta do it right.


----------

