Need help in making the right purchase of drill bits and taps. Will be using drills and taps on mostly CR, HR and alloy steel, occasionally aluminum. Ads for drills and taps don't help. Have seen drills and taps advertised as either coated, high speed, or carbon steel. Also M2, M6 and industrial grade have been used to describe them. I understand that high speed steel is the preferred. Am I correct? What's M2 and M6? Is industrial grade stated to mask carbon steel? Any other information on this topic would be appreciated. Thanks.
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Need Education on Material Used for Drill Bits and Taps
- Thread starter havnfun
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The only way to get a "perfect" drill for all materials is to purchase some of each. Soooo....we all generally compromise somewhere between the most expensive, drill anything bu diamond type drill. With the range of materials you mentioned, it would be probably most economical to buy a HSS, M2(this is a percentage of Cobalt added to improve the alloy), coated drill. There are a variety of coatings available these days, but don't fall into the trap of buying drills with coating specially designed for optimum performance in a particular metal or group. A common (and hence not so expensive) coating is TIN (Titanium Nitride) It's a tough coating, good for general purpose use. But remember, when you regrind your drills, if you do, you do lose the coating on the back of the edge. It's not a total loss, as the inside edge sees most of the real wear. That works until you regrind the split point, which does affect the inside of the flute at the cutting edge. At that point, the advantage of any coating is largely lost.
"Industrial grade" is just marketing talk, pay no attention. In fact, I'd question any supplier who touted their product as "industrial" I guess they don't mean wood?.....Oh, wait, that's an industry too. Psssh!
Taps are a bucket of worms on their own. Different materials can demand different taps. Still, a good HSS coated tap is a starting place. Hole configuration comes into play. Blind or through? Deep or shallow? Hand or power? We cold talk a long time about taps. I'll let someone else get in here on taps so I don't monopolize the question.
"Industrial grade" is just marketing talk, pay no attention. In fact, I'd question any supplier who touted their product as "industrial" I guess they don't mean wood?.....Oh, wait, that's an industry too. Psssh!
Taps are a bucket of worms on their own. Different materials can demand different taps. Still, a good HSS coated tap is a starting place. Hole configuration comes into play. Blind or through? Deep or shallow? Hand or power? We cold talk a long time about taps. I'll let someone else get in here on taps so I don't monopolize the question.
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Hello havnfun. Good question. I would suggest to stay away from the bargains at harbor freight or some of the flea market "industrial" pakages. You can usually tell something of the quality by looking at the coating. If it looks like it was painted on, can tell you to stay away. Look at the geometry of the grinding. I've seen some real garbage, new in the box. Enco has some good deals, if you can get their flyer, or look online. Even then, beware some of the "import" tools, in Enco. Double that for taps. Taps especially stick to a Hertel or OSG brand. One or two of those is way better than a handfull of imported junk that will mess up your work.
Just my opinion, some may agree or disagree....
Ed Hoc
Just my opinion, some may agree or disagree....
Ed Hoc
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It might be useful to get hold of Enco's print catalog. The have an explanation in the front of each section detailing the differences between the tools (HSS, Cobalt, Carbide, Tin coatings, etc.) and what they are for. It's not comprehensive by any means but it does help you to get started. http://www.use-enco.com
-Ron
-Ron
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your budget is a consideration..
MSC is also another good place to buy drills and taps.. i bought 2 drill indexes from them many years ago, they were like $120 115pc economy index, i still have both, with various broken drills of course, but all the normally used sizes are still there... i use one index at work, and brought the other home.. added: i bought high speed steel bits, HSS is about all you need if your working with HRS,CRS,Aluminum, 4140, and softer metals.. in harder tool steels you go up to cobalt drills and carbide drills..
as far as taps go, spend the money on decent taps, i dont think anything sucks as bad as a cheap tap... greenfield ,morse, osg, cleveland are some good brands.. i like cnc taps and starter taps for through holes. i usually just keep 1/4-20 to about 5/8-11 taps and i have a few fine thread and a couple of m8, m10,m12 just in case i need them.. the taps i use are generally High Speed Steel also.
MSC is also another good place to buy drills and taps.. i bought 2 drill indexes from them many years ago, they were like $120 115pc economy index, i still have both, with various broken drills of course, but all the normally used sizes are still there... i use one index at work, and brought the other home.. added: i bought high speed steel bits, HSS is about all you need if your working with HRS,CRS,Aluminum, 4140, and softer metals.. in harder tool steels you go up to cobalt drills and carbide drills..
as far as taps go, spend the money on decent taps, i dont think anything sucks as bad as a cheap tap... greenfield ,morse, osg, cleveland are some good brands.. i like cnc taps and starter taps for through holes. i usually just keep 1/4-20 to about 5/8-11 taps and i have a few fine thread and a couple of m8, m10,m12 just in case i need them.. the taps i use are generally High Speed Steel also.
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Don't bother with carbon steel drill bits. Carbon steel taps and dies work pretty well unless you are doing production work. Honestly I am not sure I have ever used a HSS tap or die. As far as the type of drill bits, TiN coated bits are nice, especially for aluminum, because they help reduce BUE (built up edge). The only issue with them is that if you ever want to sharpen them, you will lose the coating, and just have an uncoated HSS bit; you are going to be better off with a sharp, uncoated bit than a dull, coated bit every time.
As far as M2 vs M6, they are 2 different HSS alloys, you can look up the content and properties, but I wouldn't worry too much about the difference. M2 is the most common IIRC.
As far as what brand, I can only say, you get what you pay for. I have had several hardware store sets, and thought they worked pretty. When I got my mill-drill, I ran into issues with Z-axis height, so I got some stubby bits, and splurged on a nice set from LMS (American made, Huot index, letter, number and fractional to 1/2"). These things have a will of their own, and they push through steel like it was plastic; if you have the money, they are highly recommended, otherwise, I got a pretty decent set from OSH (black oxide, fractional to 1/2") that works pretty well. I believe it was under $50.
As far as M2 vs M6, they are 2 different HSS alloys, you can look up the content and properties, but I wouldn't worry too much about the difference. M2 is the most common IIRC.
As far as what brand, I can only say, you get what you pay for. I have had several hardware store sets, and thought they worked pretty. When I got my mill-drill, I ran into issues with Z-axis height, so I got some stubby bits, and splurged on a nice set from LMS (American made, Huot index, letter, number and fractional to 1/2"). These things have a will of their own, and they push through steel like it was plastic; if you have the money, they are highly recommended, otherwise, I got a pretty decent set from OSH (black oxide, fractional to 1/2") that works pretty well. I believe it was under $50.
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I should correct a mistaken statement about M2. There is no Cobalt in M2. That designates a tungsten-moly alloy. It is a very hard alloy, but with the addition of Cobalt, it has increased heat resistance. There is a great deal of variety in tool steel alloys used for drills, taps, and dies.
Wiki (for what it's worth) has a writeup on HSS: http://en.wikipedia.org/wiki/High_speed_steel
Take it with a grain of salt, as usual.
Carbon steel is for wood work. I should say I am speaking from experience in an environment where 1018/1020 steels were nonexistent, so I have far more experience with the use of the more specialized alloys of cutting tools, and their coatings. There's not a carbon steel drill, tap, or die in my personal shop now either. Just a waste of money. Even if you are cutting the mild, free cutting steels, or brass....or even plastic, just buy one of the highest quality your budget will allow and you won't have to worry about wearing it out, or getting dull and botching a part.
Wiki (for what it's worth) has a writeup on HSS: http://en.wikipedia.org/wiki/High_speed_steel
Take it with a grain of salt, as usual.
Carbon steel is for wood work. I should say I am speaking from experience in an environment where 1018/1020 steels were nonexistent, so I have far more experience with the use of the more specialized alloys of cutting tools, and their coatings. There's not a carbon steel drill, tap, or die in my personal shop now either. Just a waste of money. Even if you are cutting the mild, free cutting steels, or brass....or even plastic, just buy one of the highest quality your budget will allow and you won't have to worry about wearing it out, or getting dull and botching a part.
Appreciate all of the advise and personal experiences and preferences. Over the years I have assembled a large collection of drill bits under 1/2", some HSS, some Harbor Freight coated, and who knows what else. For the most part they have served me well for occasional use. I probably have no more than 3 or 4 taps of unknown material or brand. As I now begin to build a small metals workshop, my immediate need is to purchase bits larger than 1/2" for use in my recently acquired lathe and drill press. My thoughts now are to purchase quality HSS M2 drill bits with reduced shafts of 1/2 or 5/8"(ones with flats on the shafts) that I can use with both my lathe and drill press. Later as funds are available I would like to purchase quality HSS M2 drill bits with MT2 shafts for the lathe. I will probably purchase taps as the need develops and only quality taps. I broke one of my cheapies while doing a repair on my sickle bar mower and it was a "bear" to get out. Thanks.