LumberJocks

All Replies on Can You drill any steel??

  • Advertise with us
View heldercruz100's profile

Can You drill any steel??

by heldercruz100
posted 02-21-2017 07:32 PM


28 replies so far

View Ocelot's profile

Ocelot

2309 posts in 3088 days


#1 posted 02-21-2017 07:45 PM

Use some oil on the thing as you drill – also, use at least “cobalt” bits.

View diverlloyd's profile

diverlloyd

3560 posts in 2307 days


#2 posted 02-21-2017 07:50 PM

Yes you can drill any steel depending if you have the right bit. Put some oil on it and push down hard while pulling the trigger on and off. Don’t hold the trigger down that is what beats the bit and ruins your bits it’s more so that way on stainless

View sawdustdad's profile

sawdustdad

379 posts in 1334 days


#3 posted 02-21-2017 07:54 PM

Depends on the quality of the drill bit, the type of drill bit and the hardness of the steel. Most twist drills are ground with tip angles appropriate for most materials, including mild steel. Cheap bits from Harbor Freight are not going to work or last, so buy good quality drill bits. Even then, they can be resharpened or may need to be if misused.

Yes, add some oil to the cutting process to keep the bit from overheating. As an example, I had to drill 3/8 in holes in some AR400 plate steel—hardened (abrasion resistant) steel. I got half way through the 3/8 in plate before the drill bit quit cutting. Sharpened it, and added oil. It went through that plate and 5 more without any hesitation. You can use pretty much any oil you have around, it doesn’t need to be cutting oil.

-- Murphy's Carpentry Corollary #3: Half of all boards cut to a specific length will be too short.

View heldercruz100's profile

heldercruz100

51 posts in 930 days


#4 posted 02-21-2017 08:03 PM

Thanks for the tips everyone, just one more thing, this is gonna sound joke, but it isnt.. Is it ok if I use engine oil?? I have some left from the last oil change, its new, but too old to put in the car..

-- Helder Cruz

View tomsteve's profile

tomsteve

958 posts in 1669 days


#5 posted 02-21-2017 08:03 PM

rpm is important,too.

View diverlloyd's profile

diverlloyd

3560 posts in 2307 days


#6 posted 02-21-2017 08:07 PM

Yes old oil is fine

View HokieKen's profile

HokieKen

10249 posts in 1588 days


#7 posted 02-21-2017 08:23 PM

What kind of drill bits are you using? It has to be harder than the steel you’re drilling. For drilling steel, you need a HSS or carbide/carbide tipped bit. All of the above suggestions are good ones but still won’t work if you are using a cheap, mild steel bit intended for wood use only.

-- Kenny, SW VA, Go Hokies!!!

View 000's profile

000

2859 posts in 1349 days


#8 posted 02-21-2017 08:26 PM

Sometimes it’e easier to start with a smaller hole and increase the size as you go up.

View William Shelley's profile

William Shelley

609 posts in 1919 days


#9 posted 02-21-2017 08:41 PM



Depends on the quality of the drill bit, the type of drill bit and the hardness of the steel. Most twist drills are ground with tip angles appropriate for most materials, including mild steel. Cheap bits from Harbor Freight are not going to work or last, so buy good quality drill bits. Even then, they can be resharpened or may need to be if misused.

Yes, add some oil to the cutting process to keep the bit from overheating. As an example, I had to drill 3/8 in holes in some AR400 plate steel—hardened (abrasion resistant) steel. I got half way through the 3/8 in plate before the drill bit quit cutting. Sharpened it, and added oil. It went through that plate and 5 more without any hesitation. You can use pretty much any oil you have around, it doesn t need to be cutting oil.

- sawdustdad

I thought I should mention, I have this set of 3 stepped drill bits from harbor freight, and I’ve drilled over a hundred holes through 1/4” mild steel with the 6-step bit (the one pictured on the right), with oil and with my drill press. Probably 400-600 RPM. The bits are still holding up great.

http://www.harborfreight.com/3-piece-titanium-nitride-coated-high-speed-steel-step-drills-91616.html

-- Woodworking from an engineer's perspective

View Iamjacob's profile

Iamjacob

48 posts in 3076 days


#10 posted 02-21-2017 08:52 PM

Most likely you need to slow down. You almost cant drill too slow as long as you aren’t stalling to motor of your drill. Use of a drill press is best as you can use the slower pulleys but a hand drill will work.

When drilling steel you absolutely need to be pushing hard enough to be removing metal as the bit turns. If you are not removing metal as the bit is turning then you are rubbing the cutting edge of the drill bit and rapidly dulling it.

When drilling metal, you really do get what you pay for when it comes to drill bits. If you got your drill bits from harbor freight then don’t expect to get very far with them. Good quality drill bits will turn mild steel into swiss cheese with little effort.

jbay is correct. Start with a pilot hole and then step up in bit size. Make sure the the pilot hole is at least as large as the web thickness (see photo (b)) as the next size drill bit. The point of a normal drill bit does not cut but pushes the material out of the way so the flutes can remove it. A pilot hole allows the flutes of the bit to cut efficiently.

View Tim's profile

Tim

3824 posts in 2411 days


#11 posted 02-21-2017 09:01 PM

If it’s not making any progress the bit is probably dull. If it is a half decent quality bit and you learn to sharpen it, it will cut a lot better. +1 to what others said about using oil, lower RPM, and enough pressure. The amount of pressure affects the feed rate and the feed rate and RPM (speed) need to be in balance basically for the material you’re cutting.
Also as others said changing the drill point geometry can help a lot for different materials but that’s not a beginner topic really.

If you’ve got a super cheap bit none of the above will matter much.

View waho6o9's profile

waho6o9

8705 posts in 3026 days


#12 posted 02-21-2017 10:00 PM

http://www.harryepstein.com/index.php/catalogsearch/result/?q=drill+bits+us+made

I purchased this one:
http://www.harryepstein.com/index.php/norseman-29-pc-drill-bit-set.html

Great advice above. Use your used engine oil, step drill it with good bits and you’re done.

View Maximum's profile

Maximum

22 posts in 933 days


#13 posted 02-21-2017 10:33 PM

jbay has the right idea…that plus the oil.

View canadianchips's profile

canadianchips

2627 posts in 3446 days


#14 posted 02-21-2017 11:11 PM

If you have good drill bits you do not need to drill pilot hole.
I have chipped good bits because SOMEONE thought a pilot hole was a good idea !
I also use “Brake Cleaner”
An old timer machinist showed me that trick…Works well.

-- "My mission in life - make everyone smile !"

View 000's profile

000

2859 posts in 1349 days


#15 posted 02-22-2017 12:23 AM


If you have good drill bits you do not need to drill pilot hole.
I have chipped good bits because SOMEONE thought a pilot hole was a good idea !
I also use “Brake Cleaner”
An old timer machinist showed me that trick…Works well.

- canadianchips

I never have chipped a bit, drilled many a hole that way.
If you were using good bits then why were you drilling a pilot hole? lol
But I see you have me blocked so I see where your coming from.
(This is like the 3rd thread I see you have come behind me to disagree.)

View waho6o9's profile

waho6o9

8705 posts in 3026 days


#16 posted 02-22-2017 12:30 AM

View TheFridge's profile

TheFridge

10858 posts in 1935 days


#17 posted 02-22-2017 12:55 AM

Uber bad stuff. Worked in a plant that had that stuff. Killer.

-- Shooting down the walls of heartache. Bang bang. I am. The warrior.

View OSB's profile

OSB

147 posts in 975 days


#18 posted 02-22-2017 01:24 AM

Speeds, feeds, tool geometry, lube and chip removal.

The way a point of a drill bit is ground can limit the size of the bite it takes in material. If you don’t have it ground right it can bite too much which is how a drill can break when using a pilot hole (and too much pressure).

Once you’ve got a feel for a good cut, you have to peck. If the flutes of the drill get clogged with chips, the bit will stop cutting and dull rapidly. Removing the drill from the cut (pecking) allows the chips to release out of the flutes, cutting fluid to flow in to the cut and the drill bit to cool slightly. Those are all good things for a drill bit.

Pecking is also a good technique for drilling wood because sawdust clogs flutes too and since wood is cut dry, heat builds up and the bit should be cooled just like when cutting steel.

View tomsteve's profile

tomsteve

958 posts in 1669 days


#19 posted 03-01-2017 02:39 PM


Speeds, feeds, tool geometry, lube and chip removal.

- OSB

I used to run,repair, and set up screw machines. when I first started in it, I was amazed how a 3/8” drill could drill into the end of barstock 1/2” deep in about 6 seconds and do it over and over and over. usually, if I started a 10 hours shift with a fresh drill, id only have to change them( usually multiple drill bits at the different positions) out once in the shift.
the foreman saw I was intrigued by it and gave me a book to study about drills and steels.
theres a LOT that has to come together to make a drill bit do its job.amazing how just a very minute change in the geometry,feed rate, spindle speed, or even how the coolant was aimed at the bit could change the hole diameter, finish, and/or how long the bit lasted.

View patcollins's profile

patcollins

1687 posts in 3315 days


#20 posted 03-01-2017 09:37 PM

Unless you got some of the very hard but brittle steel that things like artillery barrels are made from there shouldn’t be a problem drilling it.

View cherk3's profile

cherk3

14 posts in 891 days


#21 posted 03-11-2017 09:00 PM

I agree with most posts above. I have much experience working with metal. A good quality, sharp bit is important. As mentioned above oil and constant pressure is equally important. A few things that I would like to add is drill speed. Set the drill to a very slow speed for hard metals. It is easy to sharpen a drill bit as well. Just set to standard nuts side by side and this is almost the exact angle required for a properly sharpened bit. Just ensure you have a nice gentle taper to the point. Sometimes pilot holes are used, just ensure you use the correct diameter relative to the final size hole you want. Hope this helps.

View Jim Finn's profile

Jim Finn

2724 posts in 3371 days


#22 posted 03-11-2017 09:40 PM

When drilling steel, slow speed and lots of pressure is what to look for. Steel should come off in ringlets or at least large chips.

-- No PHD just a DD214

View cherk3's profile

cherk3

14 posts in 891 days


#23 posted 03-11-2017 11:50 PM



I agree with most posts above. I have much experience working with metal. A good quality, sharp bit is important. As mentioned on the above replies, oil and constant pressure is equally important. A few things that I would like to add is drill speed. Set the drill to a very slow speed for hard metals. It is easy to sharpen a drill bit as well. Just set two standard hex nuts side by side and this is almost the exact angle required for a properly sharpened bit. Just ensure you have a nice gentle taper to the point. Sometimes pilot holes are should be used, just ensure you that you use the correct diameter relative to the final size hole you want. Hope this helps.

- cherk3


View Craftsman on the lake's profile

Craftsman on the lake

2993 posts in 3887 days


#24 posted 03-12-2017 12:04 AM

I know there will be naysayers but I have a piece of steel brought home by my brother years ago from a nuclear sub base. They used odd mixtures of alloys in various places on the boats. He was a nuclear pipe welder. I have all manner of drills and a drill press. I can barely make a dent in it with a cobalt drill. He fabricated a small draw knife years ago using it in the machine shop (so something will cut it). I’ve used it off and on for the past 30 years and have never had to sharpened it… and never been able to sharpen it. I’d like to put a better edge on it. I even have one diamond stone. Doesn’t seem to matter. I know, I know, no metal is harder than diamond. Go figure, I don’t know what it is but I can’t touch it with anything in my shop.

-- The smell of wood, coffee in the cup, the wife let's me do my thing, the lake is peaceful.

View runswithscissors's profile

runswithscissors

3057 posts in 2474 days


#25 posted 03-12-2017 03:46 AM

I always use cobalt bits, even for wood in smaller diameters. HF’s set of 29 cobalt bits seem to work as well as the expensive ones I get at my hardware store. Cobalt bits are somewhat brittle, but the HF ones are no worse than the others. The advantage of cobalt is that it can stand a lot of heat. Heat kills HSS in nothing flat.

Years (decades) ago, before I knew about cobalt (and maybe it wasn’t even available then), a guy at my hardware store passed on a tip. When drilling hard metal like stainless, use canned milk as a lubricant and coolant,. So I tried that, and it worked. You can see the milk start to boil, and in a few seconds, it’s all boiled off. So you add more canned milk.

As you can imagine, the stuff makes a mess, and unless you keep it in the fridge, it soon spoils. Then I got to wondering if miscible (water soluble) oil would work. Dormant oil for fruit trees is an example. I tried a roughly 50-50 mixture, and it worked very well. I keep a little spray bottle of it, and add to the steel as necessary. Much cleaner, and it doesn’t spoil. And this is with ordinary HSS bits. I don’t often use it for cobalt. The principle seems to be that the oil lubricates (like the butterfat in the milk), and the water cools. Unless you are really drenching the work with oil, I think you are missing this cooling aspect when you use just oil. Oh, I did recently notice that my hardware store is selling a special oil for drilling stainless, but I suspect it is the same thing as I’ve been using. And it’s a lot more expensive.

Of course it all works better with sharp bits.

-- I admit to being an adrenaline junky; fortunately, I'm very easily frightened

View KevinL's profile

KevinL

33 posts in 1800 days


#26 posted 03-12-2017 03:32 PM

RPM of the drill is very important as well as the quality of the bit. I teach machine tech and have seen drills actually “unwind” when students have purchased less quality tools. As a matter of fact, they have been dead soft on the Rockwell C scale.

Jober drills will have an included angle of 118 degrees you will want a different angle for materials such as brass because it will suck the bit into the material and cause a blow out.
To figure spindle speed:

For mild steel use a formula of 4×100 divided by the drill diameter .

Medium carbon steel 4×60 divided by the drill diameter.

High carbon 4 x (25 – 50) divided by the drill diameter. I always start with 25 and work up from there.

Some type of oil is also very important , and I would not use carb cleaner. WD 40 works great for aluminum (use a constant of 4×300 divided by diameter). It has a high concentration of kerosene in it.

Just my 2 cents.

-- KevinL

View William Shelley's profile

William Shelley

609 posts in 1919 days


#27 posted 03-12-2017 03:54 PM

I use either pneumatic tool oil, or thread tapping/cutting oil. The tapping oil is preferred because it’s thick and sticky. It’s specifically made FOR drilling and tapping and cutting metal. It’s probably cheaper per oz than a lot of the dangerous stuff you guys are using or suggesting.

Carb cleaner / brake cleaner …WTF? not only is that stuff ridiculously dangerous and toxic but it flashes off really quick, so it makes a terrible lubricant. You’d be better off just using straight mineral spirits in that case.

-- Woodworking from an engineer's perspective

View REO's profile

REO

929 posts in 2523 days


#28 posted 03-13-2017 01:39 AM

to be effective a pilot hole need not exceed the inscribed circle if the chisel edge. larger holes can create a self feeding of the bit because of the spiral form which can overload the lip of the bit and cause it to chip.

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com