[greenmoonshine]

I was just wondering where the High Speed Steel(HSS) term comes from. I was under the impression that what it stood for was the fact that since they contained more cobalt than steel that they could withstand the higher temperatures produce from drilling threw metals at a high rate of speed without softening. Now with that being said, I had a fella today that was dead set on trying to convince me that they were "made out of" High Speed Steel........, What the hell does that mean? I actually thought that he was joking at first but after 10 min. of his non stop about them being made of HSS I had to stop and think.......then slowly walk away with this still in the back of my mind. I mean, I dont think Im wrong but he was just so persistent.

[sunsetdart]

HSS is steel with more carbon in it. The carbon just makes the steel harder and easier to drill with into thicker metals.

[timothale]

I have a set of antique drill bits and a hand brace that belonged to my grandfather. the angles on the bits are different than elect drill bits. years ago I was helping a buddy build a trailer ..I could cut just as fast with the hand brace as my buddy could with his 3/8 drill cutting 3/4 inch holes. the older bits removed more metal each turn. I cut off the square shank on a bit and tried to use it in a drill press. the high speed and pressure ruined the bit in about 10 seconds.

[4 Jaw Chuck]

High Speed Steel Defined

The term has evolved over the years, old HSS from the 40's is nowhere the same material as what you find at a tool supplier today. In general there are three types of HSS available commercially today;

M2 - General Purpose HSS meant for working all kinds of steel, this is the most common "tool blank" a machinist would have in his tool box and is the material of choice when manufacturing a twist drill. The "M" prefix denotes the primary alloying ingrediant as Molybdenum. Most high quality drills are mfg with this HSS. M1 material is most commonly used for lower quality tools that may need more flexibility such as general use twist drills.

M42 - Next most common HSS, commonly referred to as "Super Cobalt" by machinists as it has higher "red hardness" for machining hard materials with still a good degree of impact strength.

T2 - A high strength Tungsten HSS used primarily for high speed turning of Aluminum where the only consideration is "red hardness" and elimination of tool "pickup" that is commonly found when machining these gummy materials at high surface speeds. It is brittle and does not handle interrupted cuts well.

HSS construction and material selection is becoming "old school" as carbide has replaced 99% of the uses for these steels in the mfg industry. The types listed above are only a small fraction of HSS types available and are most commonly found in a typical machine shop toolroom.

Don't get me started on coatings, we could be here for a month discussing them.

[Henry Highrise]

I prefer Hanson drill bits and I like the cobalt ones the best.

[greenmoonshine]

Originally Posted by 4 Jaw Chuck

M2 - General Purpose HSS meant for working all kinds of steel, this is the most common "tool blank" a machinist would have in his tool box and is the material of choice when manufacturing a twist drill. The "M" prefix denotes the primary alloying ingrediant as Molybdenum. Most high quality drills are mfg with this HSS. M1 material is most commonly used for lower quality tools that may need more flexibility such as general use twist drills.

So from what your saying and the Link you posted says, M2 has no Cobalt in it...... I thought that it did contain a little but I guess that I was wrong.
To get a bit with Cobalt in it I would have to get the M35 which also has a higher content of Tungsten. I have seen a Big drill bit set at the local Harbor Freight that just says Cobalt, I wonder which category they fall under.....The M42?
Thanks for the info
http://en.wikipedia.org/wiki/High_speed_steel
and another Wiki
http://en.wikipedia.org/wiki/Drill_bit

[greenmoonshine]

O.K., This is where I saw that the M2 bit has some Cobalt in it http://www.tec-n-tec.com/English/Riv...rillNTecAN.htm see in the bottom chart where it lists the M2 first , if you follow it over threw the different metals it lists it as having 0.60Max Cobalt, I new I saw that somewhere, Now this is there drill bits that they are selling and I have a sneaking suspicion that they are not in the U.S.

[4 Jaw Chuck]

All HSS has cobalt in it, tungsten also. Its the amount of alloying and the proportions that dictate performance.

Solid "Cobalt" drill bits (I have a set for drilling aluminum) are M42, just be aware that most consumer quality drill sets are M1 HSS with a cobalt coating. True "Cobalt" drill sets are very expensive and should not be used for drilling plain steel as they will chip at the margins.

If in doubt read the packaging, if it specifically does not list the drill blank as M42 then it won't be. There are very few instances where a pure M42 drill is an advantage anyway.

The entire "consumer drill bit industry" is full of claims of titanium this and cobalt that and these are all coatings not actual materials of construction, not that they don't have a place...but for 99% of the average people out there a plain M2 drill blank is all the performance they need. Besides sharpen the drill once and the coating is gone off the face.

I see M35 mentioned and some other HSS alloys, I have never seen them in a machine shop as they would be special ordered blanks and you would have to buy a box to get them as a minimum. The three I mentioned are the ones you can be buy commonly off the shelf, if you walk into a tool supplier and ask for a M50 HSS 3/8" lathe tool the guy behind the counter is gonna look at you funny and won't have it....you would be lucky to find T2 nevermind M35 or M50.

Those are specialty alloys and in todays world all their applications have been supplanted with cemented carbide and special arbors and tool holders to mount them.