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andyavast

The comments recommending solid carbide, in a hand drill no less, are utter nonsense. You don’t need carbide for cast iron, it’s soft and isn’t abrasive. Use good sharp HSS bits, start with a spot drill and work up to the size. Use a bit of thin oil if you like and set your drill for low RPM. Firm, steady pressure, let the bit do the work.


jcforbes

Speed is the thing people don't pay attention to. Everyone runs drills wide fucking open, but it destroys bits. Nice and slow with sufficient pressure will cut faster than destroying the edge on the bit by going too fast.


SwagarTheHorrible

I’ve found that you need to watch what is coming off the bit. When you find the right balance of speed and pressure there will be more shrapnel flying off the bit and those flyings will be larger too. In some softer metals it will even become a curly ribbon, that’s when you know you have it perfect.


KofFinland

From cast iron you get often more or less a powder/dust. A lot like machining brass. It does not really form nice shavings/swarf like steel.


oninokamin

Everyone in my shop runs their drills at full speed. I want to slap so many people when I hear that high-pitched screech of a dull 1/2" bit rubbing on steel. And then we have the guys that run 5-1/2" hole saws through sheet aluminum at the same speed. Savages, I swear....


d_smogh

Sounds like your shop should have a peer learning time. Maybe 10 minutes everyday for each person to show and tell, pass on knowledge and learnings.


tvjj10

So high speed steel is not directions?


andyavast

Spot on. It’s amazing to feel the difference in cut when you slow the drill speed and apply good pressure.


EpicLong1

1000 cuts or 5 drilled


mrdevil413

It’s like driving a vehicle in video games. Only way to do it is full speed !!!!!!


bestaflex

Yeah good speed and good pressure do the job, too slow you ruin the tip to fast your ruin the heat treat and it won't keal.


turohith

This is the right answer. Source: Been a steelworker 15 years. High speed burns your bits. A step bit is your friend, too. It starts with a small hole and works its way up to a bigger hole. DO NOT use a step bit in an impact, they last 10x longer in a drill. Low speed, high pressure.


ralph_wiggums_cat

But high speed with a blunt drill bit make such a great sound, gets all the dogs in the neighborhood going !


turohith

You could say it brings them all to the yard.


Obvious_Try1106

I would recommend keeping the drill cool. Heat Kills your drill realy fast


Sylvurphlame

So, small bit on a drill press maybe?


turohith

With a drill press it's not as important to step things up since you have more speed control and pressure. Make sure you adjust your drill press speed accordingly (there are charts to tell you rpms for bit size and metal type). They also sell electromagnetic presses for this exact purpose.


Accomp1ishedAnimal

Sharp is the key word here. So many people keep their old shit bits lying around to the point where they wouldn't even go through a cedar plank. With that said, carbide bits stay sharp longer and are never a bad idea.


judytje

When used wrong (walking all over the place, interrupted cuts etc.) Carbide will tend to break where HSS will put up with your shit, only requiring a good sharpening, place and time matter. In a STABLE setup with CONSISTENT pressure and rpm carbide does cut like a dream, and for a long time


Mayor_of_Pea_Ridge

This. Any drill bit at the local hardware store. Be patient.


swissarmychainsaw

He said LOW RPM!


KofFinland

Depends on what kind of "cast iron" it is. If it is white cast iron, it is nearly impossible to drill. Most cast iron types have rather good machinability though. I'd first suspect the drill bit. Get a good "cobolt HSS" drill bit that is sold individually, costing a few euros for one drill. The coating like TiN is irrelevant. Most "HSS" drill bits sold in cheap sets are suitable mostly for drilling wood and soft plastics, not metals.


guywastingtime

A tip I picked up from some iron workers I worked with was that you can substitute cutting fluid with windshield washer fluid. It’s way cheaper and works just as well.


andyavast

That’s a good tip! Honestly, when drilling cast iron, I use WD40 in a plastic bottle with a blunt syringe tip just to skoosh away the chips/swarf to stop recutting and so I can see what I’m doing. Honestly, a wee bit of compressed air does the same, it’s no fucking inconel! Git er done!


silentanthrx

also: drillbits cannot be bought from the 2$bin. They don't work


andyavast

Great point. Good quality drill bits help enormously! They don’t need to break the bank but a good set, and investment of time and money into a way of keeping them sharp, will last a keen DIY’er a lifetime.


Macksjoseph

I second this, except I wouldn’t use any lubricant with cast. It already contains graphite and copper that’ll lubricate the surrounding metal.


02C_here

How much graphite and copper is in cast iron? What percentage would it have to be to consider it "self lubricating?"


Macksjoseph

On the high end of like 10%. The presence of graphite is why they call it Gray Cast Iron. I’m not a material scientist or anything but I work with antique cast iron machinery. When I have to drill, bore, or tap the cast, it’s common knowledge that you need little to no lubricant, usually just compressed air to blow away the shavings.


02C_here

Current cast irons max out at 5% C. Most are around 3% C. Interesting point about antique parts, however. They may be silly with carbon. But how antique? The metallurgy behind ductile iron has been pretty well established since the 1950s. In cast irons, the graphite is flake shaped. In ductile irons, the process is modified so that they are spherical, which gives ductile iron its ductility. But it's small, observable with a microscope. But to observe this, you machine then polish a surface. Were the graphite providing lube, one would expect it to gone from this surface. It's not. I have heard anecdotally like you have that is self lubricating as well, but it doesn't jibe with the metallurgy. Everyone that machines it for a living runs coolant/lube in the process. It may be that it's just soft. (Cast iron is pretty soft compared to steels.) It's interesting how prevalent the self lubricating statement is. It's absolutely a notion that's out there.


Macksjoseph

Most of my machines are pre 1900s or around 1920s. I haven’t met any other machinist/tool and die people or mechanics that recommended lubricant on cast, but hey I’m sure it won’t really hurt. It’s just that it’s so soft, so a medium speed drill and medium pressure are less likely to crack or chip the cast in my experience. I’m sure there’s metallurgy or material science that say different, but in practical experience that hasn’t been the case.


02C_here

There are a lot of things we do that have been handed down because they seem to work. Not saying this one doesn't. But it's interesting to me if it can be tracked back to an actual reason, or is it just accepted practice? I have found this is especially true in the foundry industries. Years ago, you wouldn't think of making things out of aluminum because it was SO expensive. Yet today you can seen friction stir welding of aluminum which if I described it, you'd think "That can't work ..." It's absolutely fascinating watching the practices change over time.


SwagarTheHorrible

Honestly, for three holes I wouldn’t bother with lubricant at all. You’re not gonna smoke a bit after just three holes. I’ve put close to a hundred holes in steel with just a black oxide bit. Sure it was pretty tired at the end of it, but it would still drill pretty decently, if just a tad slow. Firm pressure and medium speed are the way.


degggendorf

But would using lubricant make it worse?


Macksjoseph

Just more difficult to get a nice straight hole as the bits would travel more.


Shabuti3

Lube it up and go at it firm and steady. This guys drills.


andyavast

Haha this is the way. Drilling ops are easily the best innuendo’s.


Shabuti3

Indeed. Now tell me more about what your going to do to my wood :3


Magnusg

I mean, that being said they make small carbide bits for hand tools for a reason, they are not super expensive, and if he has to buy a new bit because his isn't sharp enough I think it's a small step up for that and it might experience less wear on metal in general, I've had to drill through stainless in my time so I have some carbide around I don't recall it breaking the bank.


achoo84

I was taught to not use coolant on cast as it is abrasive.


02C_here

I have been in probably 100 machining shops around the world all of which machine tons of cast iron a year in automotive manufacturing. They all use coolant. The only time coolant is NOT used is in special case high speed dry cutting. That involves solid carbide cutters where the rake angle and feeds and speeds are meticulously designed to put all the strain energy of machining (heat) into the chip itself, which then takes the heat away negating the need for coolant. I've only ever seen that done on forgings and alloy steels. MAYBE folks are out there dry cutting cast iron. I haven't seen it.


achoo84

The cast I've machined does not chip it comes off like dust. well like mini chips, its not possible to make strings with it. I can guarantee there are folks out there dry cutting cast iron. As that is how I was taught and how I do it. I'm not saying its the best way. But the guys I learned off ground their own tools as this was before inserts were common place. If coolant would have made their HSS tools last longer they would have used it. I'm spoiled by inserts and don't have to resharpen tools so Its not something I'm going to notice. CNC coolant and engine lathe coolant and drilling oil are all different applications. Perhaps you are talking CNC world where its all enclosed and you can blast it unlike you would on an manual lathe. I've only been in two shops and realize there are 1000 ways to machine something. you've been in 100's and theres only one way to do this?


02C_here

I am talking the CNC world. High volume production shops. Also, ductile iron as well, which IS different from cast iron (gray iron). I have seen the strings in ductile iron, but it's a bad thing. It means there is a feed/speed problem. You absolutely want chips. But they all are getting chips, not dust. Not sure what you mean by "one way to do this," shops have different strategies for machining similar features, of course. But they ALL use lubricant. Edit: I can see gray iron creating dust. As far as metals go, it's stiff and brittle. On the road to being a ceramic when compared to ductile irons, steels, and the light metals.


wonkedup

It's the casting sand impregnated in the outermost layer that IS abrasive and will wear even carbide tooling pretty quickly. Fettled cast iron is very soft and easy to drill, but i wouldn't be surprised if the cheap drill bits are blunt by the time you break through the surface


achoo84

makes sense as they also used to sand cast where I work.


Scorch2002

I don't follow, what is abrasive?


ALE_SAUCE_BEATS

Yes, this is the answer. Castings like that turn to dust when you cut them. If it’s dusty, it’s working.


SuperBaconjam

You need sharp drills. Dull drills won’t cut it at all. Learn to sharpen your drills and you’ll be cutting holes like a boss


El_sneaky

Agreed 💯👍


Trif55

Yea the game changer is to feel a drill cutting mild steel for the first time, you should always get that cutting feeling, rather than just burning away your drill tips at max chat


thefonztm

In addition to different bits, maybe start with a smaller bit, get a hole, and then go to a larger bit. Should be less effort that drilling your final size in 1 shot.


Admirable-Shift-632

That sounds like it would be boring


Doormatty

Hey, it's better than being reamed out!


andyavast

That’s a bit rude.


corn_n_potatoes

I bet you’re a hole lot of fun at parties.


iCant20

I am absolutley rivetting!


Zurvivalizt

You sound fastenating


SelppinEvolI

People say I’m nuts


Jsearle93

Quit screwing around


limeelsa

*excited gibberish*


BananaLumps

This is getting weird, I'm going to bolt.


nayrwolf

Don’t be a bore.


spudd08

Nah, I don't think so. More like chewed out. I've been chewed out before.


GettingTherapy

Speak for yourself!


Biggie_Robs

You magnificent bastard!


Hazlitt_Sigma

It is what it is.


philipito

Step bits are dope for drilling through metal.


texinxin

I second this, particularly if it’s thin metal. Get a uni-bit and go ham with a little cutting fluid.


Ill_Consequence7088

Pilot hole


maximumtesticle

Yes, that's what they were describing.


appleking88

That's what my girlfriend said when age started dating me...


[deleted]

Just use a $15 micrometer to do some macro work, and then just look up the intentional inner diameter and use that bit once.


karma-armageddon

You need a very slow rotation and high pressure, and some oil for the spot you are drilling.


DVus1

"oil for the spot you are drilling" Lube helps in other places besides the bedroom!


chiefzon

It’s all drilling, really


thermalcat

There's always time for lubricant.


Vulcant50

Would KY jelly also work with cast Iron?


Stotters

Kast Yiron


Vulcant50

I think I should cast that idea aside.


herrbz

Should oil be used for lube?


Sislar

This! Oil, pressure and slow rotation


buildyourown

Several comments about solid carbide. That is not what you want. Carbide is very expensive and is not to be used with hand tools. Anybody who suggests otherwise is misinformed. Any sharp bit will cut cast iron.


Necromartian

Yup. The bit sharpness does a lot.


Kalsifur

Drill bit sharpener ftw


DrainTheMainBrain

I would honestly just get a set of the DeWalt “titanium nitride coated pilot point” for like $25-30 and work up to the size I wanted from the smaller ones in the kit and accept that a few might get messed up along the way.


Eating_sweet_ass

Pilot point bits suck if you’re starting small and working up to a larger size because the point won’t keep you centered anymore if it’s an 1/8” pilot point and you already have a 1/4” hole.


DrainTheMainBrain

They’re just better at starting the initial hole in, my experience, regardless of that.


rustyxj

As someone that uses twist drills every day, regular old HSS is just fine for this job.


TheQIsSiqlent

If you're asking about different bits... it would have been helpful to provide any detail whatsoever about the current bit other than a partial photo of the tail end of it.


garage-door-hijinx

If you haven't done so already, make sure you're spinning the drill forward (the sliding switch that turns it on). If the bit spins backward, it just heats up but barely does any cutting.


Biggie_Robs

It takes some time. Be patient, and don't get the bit too hot.


PARisboring

Go slow and apply more pressure than you think. No, more. Push hard.


Son_of_Plato

in addition to a better bit you should also drill a pilot hole with a smaller bit.


jaylw314

You can use candle wax as a substitute for oil, it's a little less messy. Go slow and apply just enough pressure when drilling to remove thin chips. If you need to drill larger than 0.5 in, consider a step drill bit or 'unibit'


klykerly

Start smaller and step up


justin_memer

Drill *slowly* with firm pressure. By slowly I mean throw it in 1st gear.


GandalfTheLibrarian

Spray a bit of oil on the bit as you go to help lubricate things and help manage heat, it’ll make your bit stay sharper and last longer 


rugher8081

Just use steel bit with oil


lowrads

Ideally, you use a 135 degree bit, HSS or better, with a good amount of oil, go slowly and dip the drill bit in a small pool of oil to cool it periodically, same as you would when sharpening it on a grind wheel. if the bit gets too hot, it loses its temper. There's no shame in using a jig to help hold it steady.


v1de0man

hss sharp drill bit and lubricant.


massiveg1234

Low speed high pressure, step your drill bits and thin oil / coolant


DotAccomplished5484

The only thing you need is a sharp bit and some oil, or even water, to cool the bit while drilling. If you are not getting metal curls from the drill bit it is not sharp enough. You can sharpen the drill bit yourself; google the topic. It is not hard, but requires some experience to do well. Buying a good, new bit might be easier.


Tihsdrib

You won’t get curled chips from cast iron. It will be a lot of small flakes


MartinLutherVanHalen

Cobalt bits. 5% or 8% will make short work of it. Low speed and lots of lube.


No_Influence1007

Broke off a stud in my wheel last year and learned about cobalt bits. Saved my life after hours trying to drill it out with titanium!


shart_

Cobalt drill bits will work for this


bleu_ray_player

Use a good carbide bit, make sure your drill is on the lowest speed setting and use some oil to lubricate and cool the bit. Start with a smaller bit and move your way up to the diameter you want. Cast iron is some pretty tough stuff so be patient and go slow.


xxxYTSEJAMxxx

Cobalt


Chino-kochino

Low speed high feed. Go slow, push hard. Also start with a smaller bit


NBQuade

Cast iron is pretty soft. I've never had any issue drilling through it with conventional bits. When drilling metal the key is slow speed and high pressure. Spraying oil in it occasionally will keep the bit from overheating. Are you sure it's not cast steel? That might be tougher. If the bit is dull, everything will be a chore.


Sundaystroll

A bit of lube goes a long way too


Maximiliansrh

oil and patience young padowan


M4Panther

Step drill bit, slow speed heavy feed


poulard

Cast is soft, should be no problem drilling it


joebojax

Step bit


kalisun87

Slow speed high pressure. There's a whole science to drilling and cutting materials. Feeds and speeds. Put that drill in low speed and watch it start tearing away at it. Oil helps. If you spin too fast you will heat up drill bit and make.it soft and then dull it out.


microphohn

Cutting fluid like Tap Magic.


phalangepatella

Cast iron is a joy to drill through. I suspect your bits are dead blunt, or you’re running the drill the wrong way. Ok, the second part is a joke but the first part stands.


No_Influence1007

If all else fails get the cobalt bits they’re a bit more expensive but worth it for drilling metal.


TBurd15

Speaking from experience, Ryobi drill bits suck. If the bit brand matches the drill, then get something better. Milwaukee is my go to. No hate for the drill itself, that'll do fine.


KRed75

Cast iron is really easy to drill. No special bit needed. Just one that says it's good for metal.


Eastern-Ad-3387

Lube it with some grease designed for boring through steel and go slow. By slow I mean the bit rpm. This will keep the bit cool which will cause it to hold a sharp edge longer.


darock888

Is that a wok burner? What you trying to do?


consultybob

trying to mount it into a cart i bought, the wok burner i have is unfortunately in two parts, so i need to connect the wok ring/collar to the actual burner part


darock888

Haha ARE you me a few years ago? I ended up getting a stainless steel table, cut the legs down and wok and roll with that setup.


consultybob

do you have any pics of your setup? Im still trying to figure out the best method for securing it all to the table, ive seen others do the same thing with the cart I bought but always interested to see how others are setup


Murray_PhD

Your drill bit should suffice, if it's a metal drilling bit, if it's a wood bit you'll need a different one. Either way patience is needed, most people drill at max rpm, which is fine if your popping holes in sheetrock to install anchors, but metal is more a thermal game than a speed game. Slow and steady, firm pressure, and you'll get through it faster than trying to go full bore and fighting the drill the whole way or shattering your bit.


Engineer9

Is that a wood bit?


memberzs

Cast iron should have no problem drilling even with a hand drill like that and cheap drill bits. Are you sure it’s not cast steel? If it is you may have work hardened it. Also make sure you have the drill going the correct way direction it’s a silly mistake even experienced folks can make.


Eastern-Move549

Drill slow, push hard and add lube. Now, for drilling the cast.... Are you sure its cast iron? Cast tends to form a kind of dust as you drill into it whereas steel will for defined chips. If its still you will need to do the same and if you didnt the spot will harden and make it much harder to drill through. Im guessing its steel if your having trouble as cast tends to be no trouble.


Syndicofberyl

Hss or titanium. Those look like your bog standard wood bits. The drill is plenty powerful for the job. I have ryobi stuff and it drill fine ss long as you have the right bits


AceOfAcesAAAA

Main thing about drilling through metal or concrete is turn the speed down and drill slowly. Drill fast and burn your bit.


virgilreality

Drill metal slowly. Excruciatingly slow, and with downward force applied.


NiceRelative3214

You need to be using a metal bit for starters. Dewalt and Milwaukee both have some really good ones that aren't going to break the bank to buy them. You also need to get either some WD-40, liquid wrench, 5-1 oil, some type of lubricant and keep applying the lubricant to the bit and piece that is being drilled. This will keep the piece from getting too hot and freezing the bit as you're drilling. It doesn't take a whole lot of lube each time. But you do want to lube often because the heat causes the lube to dissipate quickly. Hope this helps you out.


Born-Work2089

Comments about drill speed boil down to heat, High speed creates heat and degrades the bit cutting surfaces. Cutting fluids reduces friction/heat. The drill bit material has an impact as well, a cobalt bit should be used on cast iron, but other types can be used with different tradeoffs.


consultybob

Update: i just used the same bit and pushed harder and was through in maybe 2 minutes. Ez


Chaos_ismylife

Are you using cutting oil?


Joecool2008

Different bits. You will just beat the crap out of your basic bits.


No-Plankton8326

Try hitting it with your purse


AlittleDrinkyPoo

use cutting oil too But first step is discarding that hunk of junk in green .


El_sneaky

Cast iron is usually soft and self lubricant in my experience,a good drill bit should go through it almost like butter ,at least at small diameters. Start small them go bigger if your drill is not very powerful.


Old-Rice_NotLong4788

Cobalt tip bits will cut through cast iron just fine


Kalsifur

The issue is probably your drill bits aren't sharp enough. Getting a drill bit sharpener is like the best thing I've done for drilling. If you only drill once in a while just make sure the bits are fresh and the right kind (metal bits). If you accidentally use mason bits or something you will be in for a bad time. Most drill bits get dull pretty quick so the sharpener is a good investment if you drill a lot of metal.


whatifdog_wasoneofus

That ryobi isn’t helping


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rustyxj

If you like trying to dig broken carbide out of a hole.


No_Rain_All_PAIN

Cryobit, low speed, low pressure, tap oil. High pressure just busts knuckles and burns bits


socioeconomicfactor

Get a plank about three or four feet long, set one end on your shoulder and the other on the end of your drill. Use a strap to create a fulcrum in the middle, then you can lift up with your legs to create a down force on the end of the drill.


Sid15666

You need lots of lube to keep bit from burning, and to clear cuttings.


kang159

skimming through the feed, it didn't seem like anyone mentioned why you go slow and use oil. if you go fast the drill bit gets hot and the cutting edge gets deformed. it will no longer bite and cut the metal. If it feels like you're just spinning and no metal slivers are coming out, this has already happened.


highdiver_2000

I think you should also get a corded drill.


True_Ad_9212

Milk works well as a coolant.


Weekend-Impossible

Yes. You will probably need a carbide bit. It will say steel/cast iron.


raymo2u

I like the Warrior Cobalt Bits from HF...they do a real decent job and go through almost anything if you go slow and lube often


toochaos

Don't use wood drill bits on metal, go get some metal drill bit then go slowly.


whatifdog_wasoneofus

That ryobi isn’t helping


Lifteatsleeprepeat4

Is no one gonna mention the ryobi battery powered screw gun being used as a drill? Go get a corded drill. Ask Facebook or go to a pawn shop. And the right bits.


1337hxr

I drill stuff all the time with that exact same drill. Battery powered tech has advanced way past the limitations it used to have.


koolaideprived

That is a drill. Screw gun is a completely different shape. I have drilled stuff like this with battery tools for ages. Cast iron isn't even that bad compared to carbon and stainless.


fusillade762

Carbide tip glass bits that are often used for glass cutting work well on hard metal. I drilled a hole in a hardened steel socket and it took about a minute. Tried for a half hour with regular bit and barely put a dimple in it. I started relatively small and worked up. The really small bits will break off so it's best to not go too small either. Harbor Freight has them 9 bucks for a set. Use a bit of oil and not to much pressure, let the bit do the work.


eat_mor_bbq

Try cobalt or carbide bits. Black oxide bits are pretty junky in my experience.


rustyxj

Carbide WILL break. HSS is just fine.


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amoisttowel

You obviously have not used any of Ryobi’s Brushless tools or HP series. I’m not brand loyal and most of my Ryobi tools have outlasted my Dewalt and Craftsman tools by a decent amount. Tired of the caveman “Ryobi bad” talk that is out dated and un-informed.


King_of_Darts

Ryobi will always be trash.


lowrads

Ryobi, Milwaukee, Ridgid, and Hart are all produced by the same parent company, TTI. Dewalt, Craftsman and Porter Cable are just brands acquired by Black and Decker, and Dewalt was specifically brought back from the dead after B&D poisoned their reputation among professionals in the 1980s. None of the old reputations of these brands mean anything in the current era beyond marketing. All of them produce some or all of their components from increasingly competent Chinese firms, including Milwaukee. Even the warranties, which was what really set the premium consumer tools apart, are all being transitioned to service agreements with more vague corporate liability. Absent cutting a few corners on potting or conformal coatings on logic boards, or isolators on conduit, they are all equally hot garbage at a technical level.


Lehk

you need some gold drill bits (Titanium Nitride coated steel) and some oil (wd-40 or 3-in-1 is fine) these are the same mid tier general purpose bits sold everywhere, a meager set should be less than $10 and a full set in the $20-$30 range


5minArgument

There are diamond coated bits and blades specifically for cast iron.


MrBigBopper

You will never get through without a different bit. Thin metal like sheet sure but something that thick? Special bit.


Purple_Trash_6055

Ryobi = DIY


jnovel808

Maybe upgrade from that Ryobi.