Carbide Drills For Steel

[Karl_T]

look toward the bottom of this page: (ENCO catalog page 42)
http://www.use-enco.com/CGI/INPDFF?PMPAGE=42&PMITEM=337-3195

I was all set to order carbide drills and seen they are not recommended for use in steel. Why?

I've ordered what I'm think is the same product - carbide jobber length drills - from McMaster Carr. They worked fine.

Anyway, I'd like a set of carbide drills to use in steel, especially for when it might have hardened sections.

Suggestions?

 

[Eddyde]

I find Cobalt drills work great in harder steels, I would think a solid carbide twist drill might break easily.

 

[Terrywerm]

Many years ago when I worked in a machine shop, drill bits were HSS for most jobs, cobalt for the hard stuff. Carbide were rare and were used only for select jobs in specific materials, and then only by the more experienced men.

 

[planeflyer21]

Many years ago when I worked in a machine shop, drill bits were HSS for most jobs, cobalt for the hard stuff. Carbide were rare and were used only for select jobs in specific materials, and then only by the more experienced men.

There seems to be a real bias these days against HSS. My guess is that is due to carbide being so prevalent in commercial use, HSS is off most people's radar as a viable choice.

 

[Andre]

With carbide drills you could theoretically pop a hole right through a HSS tool bit! I have turned hardened HSS in the lathe with brazed carbide.

I know a guy who drilled through hardened wood chisels with a carbide tipped masonry bit for a project. Carbide if some pretty tough stuff

I would imagine it would be tricky to pull all the carbide bits out of your project if one shattered...

 

[TommyD]

The only issue I could see with carbide drills would be spindle run out, carbide being brittle might snap upon hitting the piece being drilled....the radial run out and all.

 

[chips&more]

If you want to drill hardened steel, then purchase the carbide drill bits pictured at the top of that referenced page. The carbide drill bits you have mentioned are not designed the same and will probably break/shatter in steel. Like said, I would get a set of cobalt. I usually grab my stubby spilt point cobalt set, love them…Dave.

 

[Tozguy]

I have been using some carbide tipped cement hammer drills that are reground for drilling steel. It is fairly easy to grind them to the exact size required for a specific job and have found them more durable than either HSS or HSS/CO drills in uncooperative steels.

 

[Tozguy]

look toward the bottom of this page: (ENCO catalog page 42)
http://www.use-enco.com/CGI/INPDFF?PMPAGE=42&PMITEM=337-3195
I was all set to order carbide drills and seen they are not recommended for use in steel. Why?

Why those specific carbide drills are not recommended for steel probably has something to do with web thickness, spiral, or other factors as mentionned in this article.
http://neme-s.org/2005 May Meeting/drills.pdf
If you read down a few pages there is some info about what is required for different materials.

 

[Chipper5783]

HSS drills work great, they are tough, cheap and easy to sharpen. If you look after them, they will last a long time. HSS is forgiving of any number of drilling problems.

Nothing wrong with buying more tools, but if it were me I'd only buy carbide drills as needed. I have drilled a few holes, some in pretty tough material. I have so far been able to work it out without resorting to carbide drills.

I'm suspect carbide drills would work okay, but the resulting hole will not be any better. I suspect the cost per hole will be higher, after all most industrial applications default to HSS because it is cheaper.