# Are some drill bits better for mechanical (metal) work than others?



## amakarevic (Apr 12, 2007)

I am looking to buy a set of high quality metal drill bits. Usually, drill bits out there on the market are not classified for metal vs. wood and other softer materials. Are some drill bits better for automotive work and metal applications than others?


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## MTN REMODEL LLC (Sep 11, 2010)

Cobalt


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## amakarevic (Apr 12, 2007)

MTN REMODEL LLC said:


> Cobalt


the Lowe's house brand ?


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## MTN REMODEL LLC (Sep 11, 2010)

amakarevic said:


> the Lowe's house brand ?


Ya know.... I'm really not sure..... Cobalt is an additive/alloy in the bit, and I do not know for certain, but I think there are different qualities of cobalt steel...

I don't know how you would know that quality... but I would suspect that Lowes probably carries a HO low/med type quality.

Just my guess


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## joecaption (Nov 30, 2011)

In order of the worst to the best.
High speed steel.
Titanium nitride coated.
Cobalt.


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## Oso954 (Jun 23, 2012)

Kobalt is Lowe's own brand of tools.
Cobalt is an element or refined metal.


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## amakarevic (Apr 12, 2007)

here we go:


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## SeniorSitizen (Sep 10, 2012)

*Drill Bits*

Both Cobalt and HSS ( high speed steel ) will work but when drilling steel don't forget that a drop or two of cutting fluid every second or two works wonders with either of those two mentioned. Search *cutting fluid* for your favorite. Amazon has it too.


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## MTN REMODEL LLC (Sep 11, 2010)

Oso954 said:


> Kobalt is Lowe's own brand of tools.
> Cobalt is an element or refined metal.


 
Oh... Thanks OSO.... never thought of that... I thought OP was looking at a set of cobalt bits at Lowes..........forgot that was their store branding.


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## MTN REMODEL LLC (Sep 11, 2010)

Fairview said:


> Both Cobalt and HSS ( high speed steel ) will work but when drilling steel don't forget that a drop or two of cutting fluid every second or two works wonders with either of those two mentioned. Search *cutting fluid* for your favorite. Amazon has it too.


And slow speed and a drill press......


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## 4reel (Mar 3, 2013)

Do not forget lubricant when drilling. The heat is what kills the drill. The lubricant is really there to cool the bit.


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## mikegp (Jul 17, 2011)

Also, for metal, the stepped up bits work nicely. You could also just start small and work your way up.


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## MTN REMODEL LLC (Sep 11, 2010)

I just had to drill a SS sink for a center mount faucet..1 3/8 hole.

SS is very hard.... and sure do not have a 1 3/8 cobalt bit.

Started the hole with a 1/4 cobalt twist.... and then went to a step bit to go out to 1 3/8.

The step bit was just a titanium coating not cobalt.

Not sure why it worked so well after starting with a pilot hole.


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## Oso954 (Jun 23, 2012)

Any time you are cutting or drilling hard metal, a little bit at a time works better than going the big bite.

Before step bits, it was common practice to drill holes 1/8 inch at a time with a bit change between every 1/8. 

Still done that way for thicker materials with deep holes.


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## 4reel (Mar 3, 2013)

*Speed*

Speed is another important factor. The faster the bit the higher the heat. Heat destroys temper in drill bits.


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## MTN REMODEL LLC (Sep 11, 2010)

4reel said:


> Speed is another important factor. The faster the bit the higher the heat. Heat destroys temper in drill bits.


Basically, your getting higher friction verse cutting.


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## jeffnc (Apr 1, 2011)

amakarevic said:


> the Lowe's house brand ?


That is Kobalt (aggravating when people misspell these things. Lowes brand is Kobalt, not Cobalt. Home Depot brand is Ridgid, not Rigid.)

You will usually see cobalt (for metal drilling), titanium (stronger and stay sharper than black oxide), and black oxide (the cheapest).


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## ront02769 (Nov 28, 2008)

Actually it doesn't bother me at all when the brand names get Ellen wrong, easy enough normally to understand what people mean. Bosch is Bosh, I still know what it means. Cobalt vs Kobalt would be the exception!

To the op, I USED to buy "the best" drill bits but found that for my purposes, medium quality was just fine. Especially in the smaller sizes, 1/8, etc.,you will break the eensive ones as quickly as the cheap ones. So in general I try to match the bit with what I need. That is, if I need to drill a 1/4 inch hole through stainless steel, I could end an hour and kill several cheap drill bits where a cobalt (maybe Kobalt also, but cobalt metal tip) will just zip through. If I am doing wood, crap holes are spade bit while finish holes are forstner bits. Ron


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## Electromech31 (Sep 16, 2008)

Ive been a machinist for 20 years, I also have my own shop.
You always want to look for HSS, next thing is if its surface heat treated (garbage). Most cheaper drills will be coated and surface heat treated. Your correct about cutting oil and low rpm. The step drill works great in thin material (thinner then step of drill). 

Sent from my SCH-R530U using Tapatalk


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