Looking for good twist drills (and maybe some advice)

[Andy]

I have some good brad point drill bits, and some good forstners, and tonight I finally got fed up with my cheap HF plain twist drills. So I'm looking for some recommendations. Thought I'd ask here, as I know several of you are knowledgeable in the machinist realm. I'll start with some background: I have a 29pc TiN-coated set from HF, which I got for ~$10. They've worked fine for drilling wood and occasional thin metal, but I needed to drill several holes in metal tonight, and killed 3 of the HF bits on what I thought was fairly mild steel (I'm recycling an old metal bed frame for wood storage racks, now that I have a home-made bed...) It definitely could have been my technique that killed the bits, as I don't know much about metalworking - I drilled 1/8" holes first, then 3/16" or 1/4", but the bits only lasted maybe a half dozen holes, and then were totally shot (or broken). Should I have used some sort of cooling fluid while drilling through the ~1/8" thick angle iron that came with my mattress? I assume that wasn't hardened steel or anything... I tried spraying the bit and hole with WD-40 while drilling with the 1/4" bit, but that didn't seem to help. At any rate, I need to replace some twist drills, and I'd like some decent ones (maybe $20-30 for a 14-16pc set? Is that reasonable?). A set going up through 1/4" would be OK; 3/8 and/or 1/2 would be nice too. I'm willing to put up with the HF set for the 64ths, so I don't think I need another full 29pc set. Even a 5- or 7-pc set (maybe

1/8-3/8 by 16ths?) would be great, if such a thing exists outside of the little B&D sets that come with cheap cordless drills. Now for some questions: Is cobalt really an advantage for durability if I'm not primarily drilling stainless steel and alloys? What about titanium? Is black oxide HSS different than shiny HSS? So far I'm considering Milwaukee and Dewalt sets from Amazon, and LV's "Triumph HSS Twist Drills". I've looked through catalogs from KBC, Northern Tool, and Grainger, but I can't tell what's really good quality and what's overpriced HF-equivalent. (OK, I can guess the $300 sets are better than HF's, but is it possible to get a decent small set of bits for less than $40?) Any other recommendations, either for drill bit sets or drilling technique? Many thanks, Andy

[Morris Dovey]

| Any other recommendations, either for drill bit sets or drilling | technique?

I don't know what the pros use, but I keep a oiler full of 30W by the drill press for drilling metals. It must work because I haven't broken a bit yet.

The bits I've been using for the past couple of years are the HF

115-bit set - and they've been holding up well...

-- Morris Dovey DeSoto Solar DeSoto, Iowa USA

[Andy]

Thanks for your quick reply! I'm sure that's ideal, but I'd really like to keep the DP table clean for use with wood. I know I can't have it both ways, so I suppose I just need another DP dedicated for metal... Interesting to hear the HF bits are working for you - maybe I'll get another set and just try to run them cooler. At their prices, I can get the bulk packs of 1/8" and 3/16" bits and call them disposable. Thanks, Andy

[Morris Dovey]

| Thanks for your quick reply! I'm sure that's ideal, but I'd really | like to keep the DP table clean for use with wood. I know I can't | have it both ways, so I suppose I just need another DP dedicated for | metal...

I have a removable MDF table on my drill press for woodworking - and I remove it for drilling metal (and I almost always use a drill press vise for those operations). When I'm done drilling metal, I wipe down the table and clean off the oil with acetone - and when I remember I give it a light coat of paste wax before re-installing the MDF top.

| Interesting to hear the HF bits are working for you - maybe I'll get | another set and just try to run them cooler. At their prices, I can | get the bulk packs of 1/8" and 3/16" bits and call them disposable.

My metal drilling has been limited to aluminum, brass, and mild steel - so my conditions have been different than yours. I have made a point of not trying to "hurry" the drilling and raising the bit out of the hole at intervals to allow it to cool while I brush aside the "shavings" and add oil. I've heard that a bit of beeswax on the bit is also a good lubricant, but have never tried it.

-- Morris Dovey DeSoto Solar DeSoto, Iowa USA

[Lew Hodgett]

Using cutting oil as a coolant when cutting metal is almost a necessity. (I can still remember a machinist who used Johnsons floor wax when cutting S/S.)

You can always keep a piece of 13 ply that gets bolted to the DP table to provide a clean surface for wood working.

If you are going to work in metal, then get a set of jobbers drills and a can of thread cutting oil.

As you realize, having the correct tools makes a big difference.

Lew

[BillinDetroit]

If he can afford them, an investment in cobalt drills might make sense, too. Not cheap ... but a 'cry once' tool.

Bill

[John B]

SNIP G'day Andy, Just a thought. Maybe your drilling technique wasn't at fault or event the bits for that matter. I've cut up a couple of old bed frames to use the angle iron for various things and the iron is terrible. It's hardness varies greatly. A mate of mine that's into metal work reckons its the worst steel you could possibly use, but of course it's horses for courses etc..

regards John

[joeljcarver]

press for drilling metals. It must work because I haven't broken a bit yet.

I recommend using thread cutting oil. It seems to work better than regular lubricating oil.

As for drill bits --- It's not complicated ---- Anything from a local hardware store or Sears or big box score works fine.

[Doug Miller]

Good tip from a recent issue of Pop Wood: fasten a 2x4 cleat to the bottom of your MDF table. Clamp it in the drill press vise for woodworking, unclamp & remove for metalworking.

[Phil-in-MI]

{snip}

Brand Name: Vermont American web page:

sure to look for HSS on label for High Speed Steel. VA makes a couple of drill bits lines, I like the HSS line. Look for VA bits and tools in ACE hardware stores, or most any real hardware store. Big Boxes may carry VA black-oxide line of bits. Amazon.com offers some VA bits. VA's HSS bits will work great until they get dull. HSS bits stay sharp for a better than average time

Phil

[spaco]

You will probably have the same results with all but the best carbide tipped drill bits. Some really expensive HSS bits might last a little while between sharpenings.

Your problem was the bed frame, not the drill bits. The bed frame angle iron is hardened steel, just about as hard as the drill bits are. I'm not saying that HF cheap drill bits are the best thing in the world. I believe that the bed frame material is a plain carbon steel, so the araa you need to drill can often be annealed with a propane torch. You need to get the spot you want to drill up to a medium red heat, then ssssslllloooowwwlllyyy withdraw the torch so the red spot gets duller and duller over a matter of about 15 seconds before the "glow" color goes completely away. Then allow the part to cool to room temp without attempting to cool it with anything, not even a blast of air. If you have several holes to drill you can perform this process, one after another, so it won't take long to accomplish. When using the typical home style propane torch-on-a-one-pound-tank, remember that the hottest part of the flame is actually a half inch or so AHEAD of the blue cone, so you need to hold the flame farther away from the work than you might think to get the hottest temp to the work. Expirement a little to see how this works.

Since you are asking on a woodworking group, does it go without saying that you want to do this in a place that has NO wood or shavings in the proximity of the heat?

Pete Stanaitis

---------------------

Andy wrote:

[BillinDetroit]

Correct. IIRC, the bed frame is typically hot-rolled and that argues for a hardened skin. I've never actually tested any, but I would not be surprised to find AISI 1045.

He can also just hit the spot he's going to drill with a grinder and knock the hardened scale part off. But we may be getting into "lotta work and not much to show" territory here.

Might even be cheaper simply to find a local steel outlet that will sell at retail and start fresh. Steel that chews up drill bits will eat a saw blade for breakfast.

Bill

[asmurff]

I can't claim to be much of a metal worker so I don't know about technique other than to use oil when drilling on metal. I've used 3-n-1 and old motor oil from when I change the it in my mower (I keep some in an old oiler my Grandfather gave me). I also really like my Drill Doctor I cut down the number of twist bits I buy considerably.

Mike Watch for the bounce. If ya didn't see it, ya didn't feel it. If ya see it, it didn't go off. Old Air Force Munitions Saying

[Hoosierpopi]

"recycling an old metal bed frame"

My buddy, "t-shirt John" does quite a bit of welding. And, when I offered him some old bed frames for his projects, he refused them saying something about the temper or some such that rendered them useless when compared to teh mild steel he used for his various and sundry projects.

My guess is that you will need to change he speed on your drill press and live with messy lubricants. You might, if you have a good torch, try heating the steel red hot then letting it cool slowly before drilling.

I invested in the DrillDoctor thing and found it offered to cut different point angles. Don't have the manual to refer to at the moment, but suggest searching google for "drilling tempered steel" for your answer(s).

n Jul 24, 6:20 pm, "asmurff" wrote:

[Andy]

Well darn it all. Here I am trying to bash my cheap tools and justify a new tool purchase, and instead I have to LEARN something. So much for that.

Seriously, thank you all VERY much for the advice, opinions, and knowledge you've shared. Since I made it through about half the holes I need to drill, I'll probably get a few more cheap bits from HF and experiment with oil etc. I'll plan on burning out a few more cheap bits before I invest in some good ones. If these old free bed frames can be as hard as you all say they are, I'm glad I didn't rush out and get some expensive bits and ruin those too.

A few specific responses: Morris and Doug: I already have a home-made table (melamine-coated particleboard) on my DP, but it's not too convenient to remove - maybe I'll work on redesigning that if it looks like I'll be doing much more metal drilling.

Pete and Hoosier: Thanks for the tip of annealing with a propane torch

- I might experiment with that too. However, I'm drilling these holes for screws that will hold up the angle iron for my lumber rack. Thus there will be a lot of weight on the screw heads - if the steel around the hole is annealed, will it be weak enough to compromise the lumber rack? I suspect that it would be just fine (this idea was far over- engineered from the start), but I'm curious for future reference. I know the steel could be re-hardened, but I'll classify that as beyond the scope of this project.

Pete: Yes, my dabblings in "metalworking" are isolated from my woodworking area, and I clean up carefully. I like my hand tool cutting edges the way they are, and I like my shop in it's current non- burned-down state. And messy metal-shaving-filled oil will give me even more incentive to keep them separate. Thanks for the reminder - good advice.

To all who confirmed my suspicions about cheap bed frame steel: thanks, and I'm glad it's not in my head - that stuff was a pain to drill, and took a while to cut/grind. Good to know. The sparks sure were fun, though! I do remember hearing that lots of sparks = high carbon steel, so I guess that should have been a hint right there.

Thanks again for patiently educating me in some metalworking basics! Does anyone have recommendations for very basic metalworking books (types of metal, appropriate tools, etc.)? I'm not interested in setting up a machine shop with lathes and milling machines, but I'd like to learn more for the occasional times when I do need to deal with metal. Still learning, Andy

[BillinDetroit]

No suggestions except to maybe take a machine shop 100 course at a local Junior College ... oh, and ask questions here BEFORE you start similar projects. There are quite a few machinists / ex-machinists on the list. Most of them are willing to answer specific questions.

Bill

[David Merrill]

A simple, practical test for machinability is to try to file the workpiece with the corner of an ordinary metalworking file. If the file won't readily (say, compared to known mild steel) notch the workpiece then cutting tools like drills, mills and saws probably will have a tough time as well.

David Merrill

[David Merrill]

Here's some additional info on scrap steel and bed frames in particular:

?lnk=st&q=%22file+test%22+hardness&rnum=7&hl=en#('Expand All' and scroll down to see comments on bed frame steel)

David Merrill