Could use tips for drilling through steel by hand

[mikey03]

No one ever taught me how to drill through steel and I never really thought to ask and I struggled a bit tonight. I wanted to drill two 8 mm holes into an old steel trolley jack to add a handle. The steel is about 4 mm thick.

Using an M12 drill with upgraded rohm chuck suggested by reddit. Norseman Magnum Premium Drill bits I got from a Prime Day special a while back.

Started out with a small pilot hole around 1/8"and it took forever. I didnt want to start too small figured a 1/16 might snap. What was weird the 1/8 bit didnt get hot at all. I took breaks every 10 to 20 seconds because I didnt want to damage the drill or battery. I used spray lube I had as a cutting oil. It took me about 15 minutes to drill this first hole taking breaks.

I used bigger and bigger drill bits I jumped up 2 to 3 sizes at a time and it was working pretty good. Only took about 10 seconds each time for each next drill bit. I tried to jump more at first but was struggling.

Once I got to around 1/4" I had to go to every size and it started getting much harder. The drill bit would bind. And whats weird is the drill bit would start smoking and getting burning hot after only 3 seconds and need a couple minutes to cool. I didnt want to risk snapping any and wasnt in a rush so I just waited each time. Each hole at these sizes took about 4 times of 3 seconds each to clear them with 2 minute break between to cool the bit.

Eventually got to 5/16" which was the closest to the M8 bolt and used a tiny round file to deburr it.

If I knew what I was doing or maybe these arent good drill bits for this job then this single 8 mm hole wouldnt have taken me 45 minutes. Going to do the second hole tomorrow. Got the blue painters tape on there marking the second hole.

In the past I used to dip drill bits in a cup of water every few seconds but looking back that might be dumb with heat shock to the bit. I did find tap cutting oil in the garage I could use tomorrow.

What can I do better? Other than taking it to someones garage with a drill press

 

[drmarkr]

Three observations from my experience, including a number of years as a machinist in my youth.

1. The trolley jack was very hard. No matter how good your bits are, unless they're significantly harder than the piece you're drilling, you're going to struggle. Cobalt or titanium are going to be necessary with hardened steel.
2. Lubricant. You MUST use lubricant on a hardened steel. You should use it on ANY metal that you're drilling, if you want maximum lifespan for your bits. Cooling? Sure, be cognizant of the heat you're generating, but without lubricant, you're just destroying your bit.
3. Speed and feed. Metals of various compositions have an ideal speed AND feed for cutting. And it's nearly always significantly slower for speed, and faster for feed, than what you think. You can source the specific cutting speeds for given bit size on the web, although without some experience it's going to be difficult to actually estimate that using a hand drill motor. Feed (force applied to the bit is your proxy) also should be optimized....and quite often it is less than what should be used.

Whatever you do, don't be that fool that grabs the drill, chucks a bit, and then slams the trigger back to full speed, completely a nihilating the bit in the first 15 seconds of his hole.

Just a few things to consider....I'm sure some of the others on here with way more experience than I have will chime in soon.

EDIT: Forgot to mention the obvious.....your bit HAS to be properly sharpened. A dull bit will be useless, particularly in a hardened steel.

 

[ez-duzit]

You're wasting a lot of time stepping up in such tiny increments, and likely work hardening the workpiece in the process. Use a new, quality, short, 1/8"-5/32" drill, with high sulfur cutting oil, for a pilot hole. Turn at slow speed, using plenty of pressure, and never stopping. Then complete the hole in one pass using a new, quality 5/16" or M8 drill.

 

[whateg01]

I think an M12 drill is going to struggle with a 5/16" hole in hardened steel in one shot, even with an 1/8" pilot.

I do hope you aren't putting holes in places that are going to compromise the structural strength of the jack.

 

[MushCreek]

I wouldn't have step-drilled it at all. 8mm is only 5/16". If the bigger drill wants to wander, put a dimple in the part with a smaller drill, or preferably a center drill. In tough metals, you want a good drill bit, slow RPM, oil, and a lot of pressure.

 

[cannuck]

As soon as I heard the times I could tell your problem from the start was not enough feed and probably far too much speed. Also, drill bits are HORRIBLE reamers and you will destory the out corner of the cutting edge in a hurry. As already mentioned 8mm is not a large hole, but probably beyond the ability of M12 drill. The secret of drilling the hole(s) you describe is to use correct speed, decent quality SHARP bit, correct coolant/cutting fluid but most of all enough feed pressure to make constant chips (you have to keep cutting as "sliding" over the surface is just making a harder substrate and duller drill bit - the constant chips are what carries away some of the heat - the cutting fluid the rest). Treat a drill bit properly and it will last a very long time (I have several that celebrated their 40th birthday this summer).

Don't feel bad: EVERYONE makes these same mistakes when they are learning - and some people never have the sense to find out what they are doing wrong and continue for the rest of their life making Chinese drill bit manufacturers rich.

 

[Old Man Roger]

To summerize, drill slow, push hard, lube well, keep cool.

 

[aShop]

I would use a good step bit from Milwaukee and an impact driver. Work smarter not harder.

 

[MushCreek]

To summerize, drill slow, push hard, lube well, keep cool.

You sound like my girlfriend...

 

[Jswain]

Mark the hole, center punch it, 5/16" drill bit with a lot of downward pressure. Once you get the hole started put some of your cutting oil in it and on the bit.

Put your drill in low speed, or feather the trigger on/off

Stepping up so many times means you're drilling with the outside edges of the bit and will dull them very quickly, yes it would need less pressure to drill bit more prone to grab, and once the outside edge is dull the bit won't drill. If you start with too small of a bit it's hard to apply enough pressure without breaking the bit.

 

[wyb2]

What was weird the 1/8 bit didnt get hot at all. I took breaks every 10 to 20 seconds because I didnt want to damage the drill or battery. I used spray lube I had as a cutting oil. It took me about 15 minutes to drill this first hole taking breaks.

In addition to the too-fast drill speed and too-small step sizes noted above…


Spray lube can do this. It will lubricant too well, it keeps the friction low so the bit doesn’t heat up, but it also has trouble getting a bite into the material. I’ve experienced this with WD-40 - switched from nothing to WD-40, and the bit cooled off but drilling got painfully slow. Switched from WD-40 to Tap Magic, and I was done 15 seconds later. All in the same hole.

 

[Old tool guy]

Is plain water an acceptable lube?

 

[drmarkr]

Is plain water an acceptable lube?

You've never tried to have *** in a hot tub, I see....

 

[mikey03]

Thanks guys since alot of you had similar comments I will just respond here in one post rather than quoting

Im not sure if I put the hole in a spot that would weaken the strength of the jack. It did cross my mind. I am putting the handle in the dead middle like where HF puts them on their jacks. Is that a good spot or did I mess up?

Low and slow sounds interesting I was using the highest drill setting on the clutch with the drill icon.

It was easy to keep the drilling lubed before the pilot hole was drilled I just kept fluid in the hole. But once that hole is drilled how do you keep it lubed without the lube just dripping away?

I really dont do this alot maybe once or twice per year but how much better would an M18 be at this?

I learned about work hardening with brass hammers on the forums here and didnt know it applied to stuff like this but makes sense. Is it possible that could be a good thing to maintain the strength of the jack even if bad for the drill bits?

Didnt know about using slightly bigger bits and using the outside of the bits instead of the front but that makes a lot of sense.

I did wonder about how much pressure to put on the back of the drill, I changed it up to see if I could notice a difference. Was worried too much pressure would snap the smaller drill bits.

Already learning a bunch from this thread so far thanks for teaching me stuff guys I really do appreciate it.

 

[dcg9381]

Is plain water an acceptable lube?

I wouldn't think so as the bits can get hot enough to vaporize water. And I don't want to spray water on metal that I'm working with... WD-40 works fine, I like "engine fogging oil" as it's a bit thicker... Hell, even motor oil will work.

OP, it drips, you've got to re-spray it as you go. Often I spray the drill bit itself so the oil travels down.

 

[Jswain]

Thanks guys since alot of you had similar comments I will just respond here in one post rather than quoting

Im not sure if I put the hole in a spot that would weaken the strength of the jack. It did cross my mind. I am putting the handle in the dead middle like where HF puts them on their jacks. Is that a good spot or did I mess up?

Low and slow sounds interesting I was using the highest drill setting on the clutch with the drill icon.

It was easy to keep the drilling lubed before the pilot hole was drilled I just kept fluid in the hole. But once that hole is drilled how do you keep it lubed without the lube just dripping away?

I really dont do this alot maybe once or twice per year but how much better would an M18 be at this?

I learned about work hardening with brass hammers on the forums here and didnt know it applied to stuff like this but makes sense. Is it possible that could be a good thing to maintain the strength of the jack even if bad for the drill bits?

Didnt know about using slightly bigger bits and using the outside of the bits instead of the front but that makes a lot of sense.

I did wonder about how much pressure to put on the back of the drill, I changed it up to see if I could notice a difference. Was worried too much pressure would snap the smaller drill bits.

Already learning a bunch from this thread so far thanks for teaching me stuff guys I really do appreciate it.

Keep the drill on the drill setting as that is the clutch, but if it has a 1/2 lever or L/H then keep it in 1 or L. If not then just feather the trigger on/off.

Don't drill a pilot hole and you won't have to worry about the lube leaking out. For 2x 5/16" hole in 1/4" plate you really don't even need lube.

If it isn't drilling with lots of pressure/slow rpm your bit is likely dull

 

[cannuck]

Just for a frame of reference check into reality: when we are talking about pressure needed for clean and continuous cuts at 8mm we mean at least 50Kg. Think about the 5x to 10x leverage on a drill press and realize in those machines you would be well over 100Kg for most work at that size. I do NOT recommend stop/start with the drill, just lower speeds than you seem to have been using. BTW: really fancy drill presses control the rate of feed, not the pressure. They use a gear drive to make sure the bit advances constantly.

 

[mikey03]

Good stuff yeah no pilot hole means the cutting fluid can stay there easily. Obviously now that you said it lol

I was doing it the wrong way as you guys taught me. But by the time I got to around 1/4" the drill could only go for about 3 seconds before the bit got smoking hot. Is that because I was trying to use it as a reamer instead of a drill and just cutting with the outer edges?

Okay something just clicked in my head. You guys ever hear stuff and it doesnt fully make sense at the time until years later and then you feel stupid lol

When you guys first said slower speed I was thinking a lower setting on the clutch which seemed weird. But I never really thought about how the clutch worked before and now I realize its there to tell the motor to stop if you hit resistance to limit torque and the drill setting is infinity resistance just keep going. And I can control the speed by hitting the trigger less.

For some reason in my head I confused the clutch with being a speed setting. But yeah I was going full speed on the drill yesterday and just pausing every little. Im really glad I am asking this question and now Im wondering what else I have been doing wrong without realizing it

 

[mikey03]

Just for a frame of reference check into reality: when we are talking about pressure needed for clean and continuous cuts at 8mm we mean at least 50Kg.

oh wow thats alot more than I’d have guessed thanks for clarifying. That’s like half my body weight

at what point should I be worried I’m damaging the drill motor or the battery? It’s cheaper to replace a drill bit for 5 bucks than a battery or a drill? There got to be some max time I should limit running them for without a break?

 

[cannuck]

On most drill/drivers the clutch is ONLY for limiting torque when driving screws. You should have a "drill" icon for a setting the locks the motor solidly to the chuck

 

[Old Man Roger]

You sound like my girlfriend...

Listen to her, she knows what she wants. It will get you BLT.

 

[wyb2]

Is plain water an acceptable lube?

Despite the other comments, I’ve actually found a cobalt bit and tap water is phenomenal for any significant hole depth in 300 series stainless. Already had the cobalt bit, but water was suggested by an old sailor walking by, and I was impressed with the results.

Downside is you really need to keep it coming (the water and the drilling progress), so a helper with a hose is really the way to go. Same idea as CNC flood coolant, which I believe is often water-based. So it’s not super practical for parts/areas you aren’t willing to spray with a hose.

 

[Old Man Roger]

Is plain water an acceptable lube?

Water isn't great as a lube, or a cutting oil, but a sufficient amount will keep a bit cool.

I used to drill 1 inch holes in 1 inch plate using the garden hose to keep the material and the bit cool.

 

[mikey03]

If I’m putting 100 pounds of pressure on the 5/16 bit with my body weight how do I keep myself from getting hurt when the hole is done so I don’t smash the drill and my hand down into the ground

btw the cutting lube I found in the garage is a jelly so it will hold up nice

 

[Old Man Roger]

If I’m putting 100 pounds of pressure on the 5/16 bit with my body weight how do I keep myself from getting hurt when the hole is done so I don’t smash the drill and my hand down into the ground

btw the cutting lube I found in the garage is a jelly so it will hold up nice

Feel and sound should change as you get ready to break through, when you feel it, ease off.

 

[cannuck]

To summerize, drill slow, push hard, lube well, keep cool.

Are we still talking about the jack?.....

 

[mikey03]

I tried some of the suggestions but made a mistake I think or maybe my tools arent good enough to do the job properly but I did get it done and it was easier with some of the ideas I was able to do.

I started off trying to make a dimple with a 1/8" drill bit. Used the cutting lube jelly I found. Switched to 5/16" and I had the jack on the floor and got a kneeling pad and was putting about half my body weight on there pushing down into the back of it.

The drill bit was wobbling a bit, it was hard to keep it square and straight in this position so I decided to make the 1/8" drill dimple a little deeper.

Then went back to the 5/16 and I was getting tired every minute or two and needed to take a brake. Its not easy to put your body weight into this and also carefully hold the trigger down just right and then hold that constant.

After about 10 minutes with some short breaks I looked and it wasnt making much progress. I think the problem is when I did the 1/8" the second time I didnt make a full pilot hole but I went deeper than I should have and now the tip of the 5/16 bit couldnt make enough contact.

What I figured out is to just make the dimple no deeper than the head of the bigger drill bit could touch all around it.

So I went back to the way I did it last night which I know now is wrong but it didnt seem like it would work because the drill power or the drill bit or maybe I made the dimple too big. But this time I had the cutting jelly and I went really slow and added more pressure. And man that really did make a huge difference!

So even though I did it the wrong way using the drill bits like reamers, it worked a lot better. And also when I got to the big drill bits they didnt get hot but the jack got hot around the hole spot. I think the cutting jelly transfers the heat to the object. Last night the drill bit got burning hot after 3 seconds and the jack never got warm at all.

I wasnt able to feel when I was getting close to the end. Putting half my body weight leaning into it, doesnt feel very different

I feel bad I wasnt able to do it exactly like you guys said but I did apply a few things and learned alot.

 

[speed bump]

Put it on 2 on the drill and 1/8" pilot. Put as much pressure as you can on the drill, if the bit isn't smoked it should go fine. 5/16" drill put it on 1 and lean on it was until it starts making chips or curls. Drill until you can't grab the tip of the drill bit with your bare fingers, let it cool and repeat. Cutting fluid is nice but as long as you let the bit cool down not that important.

 

[Jswain]

Post some pics of the end of the drill bit you were using.

A Norseman bit should drill through 1/4" like butter, unless it's messed up from your first attempt.

Might be time to learn how to sharpen drill bits, or replace the few you used and use better practise on the next run. Are the holes right next to a weld or bend or something? I just can see it being that hard.

 

[cannuck]

If your 5/16 bit didn't make chips it is too dull to use. Is this the same one you overheated on last hole??? You can't use an overheated or dull bit and you really need to be good at it to sharpen it yourself.

 

[Old tool guy]

You've never tried to have *** in a hot tub, I see....

I have tried to drill in a hot tub …

 

[Jswain]

I have tried to drill in a hot tub …

It was probably more like a centre punch, let's be honest...

 

[whateg01]

It was probably more like a centre punch, let's be honest...

Not a ***** punch?

 

[Old tool guy]

like a centre punch

No, it was like a center punch … with a rubber mallet.

 

[jessesandy]

Just drill a 5/16" hole in one go.
Use oil, not spray lube. At least motor oil.
Push really, really hard and spin the drill really slow.

 

[Old Man Roger]

As mentioned above, you probably dulled your bits in previous attempts.

 

[RoninB4]

Some good advice from others regarding speed, sharp drill bits, cutting fluid, and pressure. Speed does need to be slow enough not to burn up the drill. There's a formula for determining speed with any cutting tool per the material being cut.

How to determine speed in a hand drill? I usually go by a visual aid. When the flutes of the drill start to "disappear" that's as fast as I want to go. It's not exact by any means but it's at least something to go by. If the chips are coming out yellow you're going a bit too fast with HSS or Cobalt. If they come out blue you've probably already burned the cutting edge and might be work-hardening the material. All materials to be cut are grouped by machinability, some are more difficult than others. SS needs to be cut about 3/4 - 1/2 the speed of regular mild steel. If it's tool steel or a weldment then it's going to be difficult and you need to read up on this before attempting or you may ruin the project.

Cutting fluid is important, any fluid is better than none most times. WD is ok for aluminum but I find it too thin for ferrous (steel) materials and certainly too thin for SS. Don't like using spray for drilling, too much fluid everywhere. I prefer using real cutting fluid or at least used motor oil in a small container (spray can cap or similar size) that I can dip the drill into. Fluid cools off the cutter and stays on the drill. Dip every 5 seconds or so. Smoke coming out of the hole indicates if there's fluid in there, when it stops you need to dip again.

The cutting edge MUST be sharp or nothing else you do will matter. If you don't see chips/curls coming out of the hole then you're not cutting. If you're not cutting you're likely work-hardening the material and making it much more difficult. SS is notorious for this. It is essential to learn how/when to sharpen a cutting tool like a drill bit. It just takes a little practice (and a tutorial) on a bench grinder to learn this. After 40 years of machine shop work I still run into instances (weld, hard spots, Chinese metal) that dulls the cutting edge and I need to touch it up, sometimes more than once if the material work hardens. Failure to keep a sharp cutting edge is frustrating, counter-productive, and can lead to injury. Learn to sharpen drills, it pays off every time drilling becomes more difficult than it should be. Carbide drills should be avoided unless you know what you're doing or are drilling masonry. Carbide can create more problems than you'll want.

Pilot holes and step drilling? At least two factors to consider and both are opinions. Drilling full size (with a starter dimple) means full engagement of the entire cutting edge. Not a big deal with a drill press but a 1/2" hole in steel can be a workout. A pilot hole will be far less pressure needed but if the pilot hole is too large it can be rough starting (chatter) of the larger drill until it fully seats. Drilling full size (blind hole) can hold cutting fluid in, it also means chips will also be retained and either foul the cutting action or have to be re-cut. A pilot hole can allow the chips to fall out. Step drilling also has potential problems. It can be a good strategy for drilling 2" holes if done properly. A drill has to have enough material being cut (amount of cutting edge being used) or it will "grab" the drill. If only going up one drill size there's a good chance the material will "grab" the drill as it tries to spiral though (following the flute helix) and perhaps break/shatter, brass is notorious for this. How large a pilot hole? If I even use one I try not to make it larger than 1/8" for a 5/16" hole.

Pressure? Enough to make chips/curls with a sharp drill bit. When the chips become long continuous curls just briefly pick the drill up a fraction to interrupt the cut.

How to know when break-through will happen? A valid concern because at break-through there's a real good chance the drill will grab that last little bit of material and either spiral through, shatter, or you'll slam your hand drill into the work. I always do a quick measurement (need not be exact) and wrap a piece of tape around the drill bit, use a paint marker, or chuck the drill bit far enough into the chuck to stop further drilling. As you approach the break-through point (stay 1/16" above it) you need to back off the feed pressure and focus on controlling the pressure so it still allows cutting without snagging. This is true even with metal working machinery. I'll use my non-trigger hand to apply back pressure against the feed direction but it's a matter of being sensitive enough to "feel" when I'm about to break-through. At that point you should feel the drilling pressure get much easier all at once. Be careful at this point and back off your pressure.

This has been far more long winded than I intended and none of it should be considered the gospel, it's just my opinions. Hope it helped someone.

 

[cannuck]

I will make only one comment on Ronin's excellent post #37. I agree SOME coolant is better than none but please understand that actual cutting fluids not only cool and lubricate but some chemically enter into facilitating cutting through surfactancy. Also, there are different cutting fluids for different materials and processes. If at all possible, use right fluid for the job. In my shop, most drilling is done with my shop helper spraying water based fluid (A10) from a pumped vessel. Not always ideal, but as we started off here: some is better than none.

 

[whateg01]

It's a guy in his garage adding a handle to a jack. I don't think he's going to stock up on 13 different cutting fluids for every type of material.

 

[cannuck]

It's a guy in his garage adding a handle to a jack. I don't think he's going to stock up on 13 different cutting fluids for every type of material.

More people are likely reading this thread and the OP clearly has asked for advice, so why not tell him the whole story and let him take what he wants from the conversation? Further: why would I treat a hobbyist any different from a tradesman when information is requested or required?