Drilling Hardened Steel With Masonry Bits - Not A Lifehack
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- Опубліковано 20 тра 2023
- G'day everyone,
A bit of a shorter video this week. Is it possible to use masonry bits to drill hardened steel or HSS? Probably. They have carbide tips which will do most of the drilling so they should have the hardness to drill hard metal. Couple that with being much cheaper than a solid carbide drill and you have the makings of a pretty good lifehack. Sounds too good to be true. - Наука та технологія
A bit of a shorter video this week. Gearing up to do a long build series (something to the tune of 10 weeks/videos) so a short fun video like this is all I could get out this week. Stay tuned. Cheers
EDIT 22-5-2023: I think I might have overlooked a discussion on regrinding the tip, maybe better for drilling steel. Seems like other people have faired better than me in doing so. I thought I could get away with using the standard grind, which might not have been the best assumption. Definitely something useful here, but best used in specific situations.
Yeah, I was about to comment about maybe regrinding the geometry on it to something more reasonable.
Another thing to consider: while full sized drills are pretty expensive, carbide center drills and spot drills are a bit more reasonable, and probably worth it to get your hole started.
Interesting video. I wonder if the end results would be different if you were able to start that hole with a smaller masonry bit. I wonder if when starting the hole that you also do not drill all the way through the material, then switch to the larger bit.
Food for thought, as I do not have the need for hardened steel.
I needed to put a hole in some hard steel to put a lock thru standard hss did put a dent in it but burnt up almost instantly so I did the masonry bit trick went thru with smallest one I had 3 3.5mm and then used 6mm 8mm and finally 10mm I did ticket the tip with the grinder to square the cutting edge up only having aluminium oxide its not going to shape the tip much at all but enough
So I treated it like you would a carbide inserts tool and ran the drill as fast and with as much pressure as I could seemed to work ok made some red hot chips and swarf but it got the job done
затачиваю режущую кромку, первое касание - коротким сверлом
lifehack your arm for a band saw! you elbow will thank you in 20 years.
You definitely need to sharpen the end
I have used one running backwards to drill out a broken tap - had to re grind the carbide tip so the cutting edges were on the opposite side . Also don’t throw away your used parting tool inserts , you can braze them to a steel rod to make small drills - takes a bit of grinding but you essentially create a spade bit type of drill .
We braze the bit to square stock to cut slots in aluminum 1/4 " thick
Yes I do this too. Sharpen it backwards and run the drill in reverse to drill out broken bolts and stud's.
Masonry bits don't really "cut" as such - it's the impact that creates the hole, and the rotation between impacts serves to keep the hole round. Basically a rotating chisel. So it'll definitely need grinding to cut steel!
Done this for years for hardened spring steel. The trick to not chipping the carbide is go slow when you are breaking through the back side. I've found , that's when the chipping usually occurs. Obviously not for precision location holes, but on clearance holes for bolting things together, hard to beat the price.
Any tips on sharpening the...tip? On a bench grinder. Seems like it'd be wasy to accidentally anneal it and end up with a tip thats too soft
I have experience with this, I did my apprenticeship in a toolroom making press tooling for sheet metal parts. In a few situations wee needed to drill through dies after they'd been hardened, start holes for wire EDM modifications etc. So it was usually hardened K110 or Calmax which is pretty tough stuff. Solid carbide drill, yes they could do it but tended to shatter after a while because of the chatter and forces involved. The masonry drill was perfect for this because of the soft steel shank which let it absorb vibes and bend without shattering. The key though is sharpening the cutting edges with a fine grit diamond grinding wheel. Then it works perfectly for numerous uses. Also have to keep it cool with lubricant or else the solder melts and the carbide goes bye-bye. You can do a starting spot with the solid carbide drill.
If you want to go through hard steel, not quite as hard as HSS or tool steel, you can grind a standard drill bit to have a very shallow angle on it. Almost a flat bottom drill but with just a slight tip angle. And I’ve actually drilled through some hard metal with cheap drill bits and it actually works really well. The hardest part, no pun intended, is getting the drill started without it walking.
what about putting a piece of stock with the desired hole size in it on top to use as a drill guide/bushing ??
@@practicalplinking6133 yeah that would probably work
Thank you for your video, I came on here looking for help I spent 3 1/2 hours trying to drill through hardened steel I got about half way through it was only 1/8 thick. My hands were starting to get blisters that is when I found you and your video which saved my hands. I had high speed metal bits broke two of them I knew I had 3 masonry bits the same size but used so I finished the other half in one hour instead of 3 1/2 hours and if those bits were new who knows how short the time would have been. I got my one whole drilled and saved me from going to the big box hardware store. So it does work and when that tip is gone your out of luck I am glad I had three used ones to finish. Thank you again.
Don
I've ground a cutting edge on the drill with a green stone on my bench grinder in the past... worked reasonably well for the one hole I needed.
What a wonderful tip! Used an 11mm concrete drill to widen the neck of an impact socket just enough to accommodate the long bolt I was trying to get out. Great!
i have successfully done this many times. My late father in law, an experienced machinist, showed me how. They do it in the work shop for small jobs where the right sized bit is not on hand. The crucial thing is sharpening the carbide tip, to give a workable relief angle. Pretty easy to do. I have drilled stainless and hardened steel (old files). Also, using cutting lubricant/coolant helps to prevent overheating and failure of the drill bit.
That's awesome I was trying to drill through hardened steel and I just couldn't do it without buying carbine drill bit I just couldn't do it came across your video and was able to finish a job thank you so much
It works fine if you sharpen the carbide tip a bit first with a diamond wheel or file, it will last many holes then.And a dab of cooling oil wont hurt either :)
The only thing you need to watch out for is heating it up to he point were the brasing melts!
I'm surprised that he even managed to do anything with that dull point.
I've actually managed to grind them on a bench grinder, but it needs to be the correct stone, otherwise the disk turns to dust 😬
@@daniel635biturbo correct green grit wheel is what you need
@@daniel635biturbo I've used diamond wheels.
Been using these since the 80’s. Couple tips. Carbide ball mills work great as a spot drill if you have access to them. Also, if you need precision, step drill it with a smaller drill first. And finally, slow your spindle down a bit and use a little cutting oil or coolant. They are definitely not as accurate as a proper twist drill but have salved my butt many times.
I keep a bunch of masonry bits around. I regrind the carbide tip for cutting metal and they work great. Not only can they stand up against harder materials, but they are essentially a spade drill, so they don't wander like twist drills.
Spade drills definitely still can wander. They just resist it a tiny bit more than a twist drill since the cross section is stronger.
However masonry bits still are fully fluted, the fully fluted nature of twist drills is what makes them more susceptible to wandering. As such masonry bits will wander similarly.
Depending on the part being drilled you can also anneal it in the drilled area if that isn't an issue. You can typically use regular hss drills doing that. We used to anneal induction bar for drilling back in the day before buying proper carbide drills.
Yes I do this often. But I grind geometry into the carbide first. Leave the rake at zero degrees and grind clearance until its sharp. You have to take a fair bit off on a new drill. Automatic feed is a must or else the carbide will break on the way out the other side of the hole. This is due to the feed rate drastically increasing as the bit exits the hole. I've also sharpened the carbide backwards and run it in reverse to drill out broken studs and bolts. Works well.
Wow, thanks for the video. I was really wondering about this.
I sharpen masonry bits with a 30mm diamond disk in the dremel, then hone with a $24 diamond stick from bunnings.
Same profile i put on any HSS bit.
My day job is maintaining a very cantankerous old building. There is no way under the sun or moon I could get a proper carbide drill past the budget troll, but those masonry bits would sneak under the radar. I'm filing this in my "Dirty Tricks for Ugly Days" box, cheers!
I always love how management scoff at paying for the proper tool or part from the start but are perfectly content buying a cheap alternative over and over again.
везде одно и то же - дилетанты управляют знающими мастерами
I've used masonry bits on hardened steel several times. When necessary, I use a center punch first to keep the bit from walking.
Gday, definitely works and I’ve seen this done before on high tensile plate, good thing if you’re stuck mate, thanks for sharing, cheers
Decades ago, I used a drill bit like this to drill a hole in a piece of hardened drill because the only drill of this size had died in combat. As a coolant, I had only water available, drilled with an ordinary market drill. In some situations, even using a nail as a drill bit can help get the job done.
I started a project needing to bore through what wasn't really hard steel but it quickly dulled the carbide bits I had. Most of the whole set since I varied the bits I would use to size up to the hole. After one round of dulling the factory sharpening and another of dulling my own sharpening, which happened much faster than the factory sharpening, I decided to use the half inch masonry bit I had left over from a one off job I did for someone. After seeing how much better that worked, I bought a pack of five eighth inch better quality carbide bits and got through the remaining four fifths of the drilling part of that project in the time I spent on the first fifth.
Masonry bits don't come in a very wide range of sizes, but if someone wants to compensate for the cost of drill bits with their time, planning a project around the size of hole you're going to get with a masonry bit, is worth it.
While I haven't reground the tip before, typically a masonry bit is my home-shop "emergency dill" method.
If I accidentally overheat what I'm working on and it becomes annealed, or if I'm drilling something hard, the next step is a Carbide Masonry bit. I have however, taken a little time to ensure that I have decent ones (sometimes $5-10 each).
They work decently, however as noted, they don't make PRECISION holes.
Use a dremel with a little grinding ball stone or diamond crusted ball, you can make a nice neat divot in the material, like a "centre punch" for hardened material but a bit bigger and deeper. I like this technique because you can inspect and "walk" the divot position as you deepen it to get accurate location.
Then you can drill with a heap of force and the divot will hold the drill steady right from the start.
I once drilled brass with a drill bit on concrete. This helped me a lot, because before that I broke 3 ordinary HSS drills.
мягкий материал просит специальную заточку
@@kozka5302 я узнал об этом недавно, на канале @Clickspring ) до этого я не понимал, почему сломал несколько свëрл в латуни)) 😃
You can buy proper drill bits with the same construction, using a HSS shank/body and a carbide tip. Just that on these they have proper angles and are meant for this purpose. Probably more expensive than most masonary bits, but much less than full carbide bits (and less prone to break on less than ideal rigidity setups)
Do you know what they are called?
@@nosuchthingasshould4175 Google Carbide Tipped Drill Bit for hard steel, they look similar to Masonary Drill Bits but have a standard Gind and Flutes.
@@nosuchthingasshould4175 Bosch multiconstruction.
@@65cj55 thanks
@@markrainford1219 thanks
TL;DR tried this a few times and found the carbide tips on masonry drills vary extremely greatly in quality, some break/chip/blunt attempting to use them and others just eat your bench grinding wheel like no tomorrow trying to regrind the shape of the tip or touch up after use... i spent 20 mins on a bench grinder with a 10 or 12mm drill and only just managed to get it marginally better it was hard as an old coffin nail...
I needed to drill holes into a knife blank I had cut out of a 24" HSS metal cutting circular saw blade. The masonary drill bit worked. Barely worked but one drill bit has been enough for three holes. Not beautiful but good enough and the holes are covered by the knife scalea and not visible anyway. Still have lots of saw blade left so I will need to buy a new masonary bit now.
If a diamond wheel is used to correctly sharpen the drill bit, it should do much better.
Probably, I guess that must have glossed over thinking that. If I was using the cheapo bit I would have had to. Cheers
SiC grinding wheels cut WC well enough. Diamond is not always necessary.
Regarding drill geometry issues, Michel Uphoff made a 5 video series on an absolutely stunningly elegant n sexy compact bit grinder that could dress that bit [as well as more complex cutting geometries] for better results, worthy of your attn.
See you next week, droogie. Love the channel!
I've been following that build myself, and its quite a nice little set up.
@@artisanmakes Fully adjustable on 5+ axes and sooo compact by comparison to the traditional tools. THAT's sexy.
Also, Brandon at Inheritance Machining runs a nifty channel with some great projects. Again, see you week, matey.
Cheers, brandon is a good bloke
Thank you! 😊
@@Michel-Uphoff VERY elegant design, yours! I was thoroughly impressed by it. Cheers, Michel! Keep designing.
Great tip, I'll keep that in my bag of tricks! I don't even want to think about shop life pre-band saw! :)
Interesting video.Thank you.
Locksmith drills are what you want. Like a masonry bit they are a normal steel drill with a carbide tip, but they are ground to be suitable for cutting the hardened steel of locks. They are cheap and work well, they also cut very close to their nominal size.
You can of course use a masonry bit as you have shown (and I have done it myself). It really helps though if you use a diamond file or diamond grinder to sharpen the tip into something closer to that seen on a HSS bit.
Have to be careful in how much attention we bring to your comment...or the price of locksmith drills just went up! ..thx for the tip!
A real test of a life hack... always usefull ! Thanks !
Your creativity is amazing IQSon... something that was questionable to me before. 👌
I had to use a 300mm masonry bit to drill out an engine mounting bolt from a ducati. Had to go through from the opposite side of the engine. The masonry bit worked really well in that steel.
I have done this before! I was trying to replace the handle of a knife and needed to make the holes in the tang a bit bigger. Don't know what the steel was but it was very hard and standard drill bits did nothing. Then I found the masonry drillbit trick and tried it. Yep, it worked! 😀
I've heard that grinding some metal cutting geometry on these helps a lot
This solution is the perfect remedy in my case!
I drilled two decorative holes in a knife handle, through the aluminum handle scales and the hardened steel knife tang. I believe the first drill I used was carbon as it cut nicely. After that each drill size up became less effective until nothing would work. I turned to a grinding bit which was tapered, but that left a messy hole and the tang consumed the bit fast. Also the aluminum clogged up the grinding bit. I finally gave up, setting the knife aside to perhaps hand file with a diamond file or purchase proper carbon bits. This solution/\ is the perfect remedy in my case! The holes won't have diametral accuracy but far better than what my hand filing could achieve.
I use Bosch Multiconstruction on hardened steel. It's a universal drill that has a carbide tip, but with proper tip angles.
I also use the Bosch multi drills on hardened steel. They work a lot better than standard percussion chisel type masonry bits.
Aye it works (when you re-grind the carbide to a better shape), have used one to drill stainless too which usually needs a very hard cobalt or carbide tipped 'locksmith' drill.
I try to always keep a set of carbide tipped locksmith drills around though, they're really useful and go through anything but they're basically like these re-ground masonry bits.
Masonry or concrete dills are meant to cut with hammer or percussion drills. they are designed to chisel and chip the material. Best way I found and it worked very well for me is low to moderate RPM and coolant depands on drii dia. I managed to drill screw extractors and brokon off taps
Masonry bits work really well on (unhardened) damascus billets (e.g. for making a 'raindrop' pattern). I have used the red 'Alpen' brand masonry bits with great success, even though they barely leave a mark on basic low-carbon structural steel.
In a pinch I could see this saving the day when you just need that one hole in a piece of hardened stuff. 👍
what about a drill guide bushing for better dimensional control?
I have used a 18mm masonry drill to drill a couple of holes in 1/2" Bisalloy 500, HSS wouldn't touch it and a masonry drill was all I had so I ground the right geometry on it and gave it a go and it worked, no pilot hole and plenty of coolant.
The most likely scenario for me is to find a piece of carbon steel that is hardened in an awkward spot so if it would cut that I am interested, I don't often use HSS for anything as I can't harden it. (thanks for sharing a workable honest version of this particular hack)
In my daily job we machine cast iron, and if we need lots of non standard size holes we use masonry bits, regrind them to the propper angels and it can drill as much holes as a solid carbide one (2-3000 holes). But with steel it does not work that way.
Just judging from the masonry bits I've had, I would probably start by sharpening the bit with the little diamond wheel that came with my Dremel tool. Just to make a sharper cutting edge. This could be a great "This saved my butt" hack.
You could make the case for that if the bits needed it. I thought I could get away using the standard cut on the good bit but didnt seem to be the case. If you are good with griding drill bits it could certainly work.
@@artisanmakes Luckily that is a skill that I picked up years ago. It sucked in the moment because the boss wouldn't buy a drill sharpener, but now I'm glad he didn't. If you can't sharpen them yet, it's well worth devoting a day to learning. From your work that I've seen so far, you should be able to get them cutting within .005" easily in a day.
@@artisanmakes Some sort of punch to make the starting hole could have prevented the bit from walking. Also I wonder if a bit of cutting oil would have helped the bit last longer ..
@Artisan Makes I second that, definitely spend the time to practice sharpening drill bits, it's not that hard to get dull bits to bite again, maybe not as sharp as factory, but good enough. In the ship yard I sometimes got away with grinding them on my angle grinder.
you have to sharpen them first with a green stone, put a sharp cutting edge on it as best you can, and then they work quit well, and they'll last depending on how well you sharpen them. It's a fairly good hack though. Thanks for sharing.
I have a hardened pin broken off in a hole. I just need to cut a hole in it so I can get ahold of it with something to extract it. This should work great for me, thanks!
I've drilled some small holes in hardened circular saw blades with masonry bits that were sharpened on a diamond plate. It worked, just.
Reshaping a masonry drill bit tip to resemble two inserts on a shaft makes a huge difference, drilling through masonry is so much faster but heat needs to be controlled when drilling steel....👍👍👍
I have used a standard masonry bit to drill through sockets for a tommy bar, after killing several standard drills.
Produced a lot of heat and socket glowed red around the hole but it got done
Hole a bit large as mentioned
I believe the “do-all” bits have a sharper edge and are probably better geometry
This is the sort of thing this "hack" is good for. We're not all machinists. Sometimes you just need a hole in something hard. I've done this twice in the last 10 years. Just as in this video, it made an ugly hole and the drill was ruined, but it was good enough for my needs.
I purchased across a really cheap set of the Milwaukee shockwave multi-material bits at a bargain store. I drilled a 3/16" test hole in the handle of a cheap wrench - probably slightly hardened, but definitely not 66 HRC. The hole was clean, reasonable round, and just slightly oversized. Better than my results with the masonry bits, but visibly imperfect. However, there was no visible wear on the bit. This is anecdotal, but there seems to be a difference between the multi-material and masonry bits. That said, I compared them my Milwaukee shockwave concrete bits, and the edge geometry looks identical. Both are geometrically similar to my Bosch concrete bits too. If there are differences between the concrete and multimaterial bits, it must be in the metallurgy.
Ive used this trick a few times over the years to get me out of a pinch. It works well if you take the time to grind the correct geometry on the business end
I’ve used this trick to drill pinning holes for a knife handle when the tang was to hard for a conventional drill. Blade was made from an old mechanical hacksaw blade and it was as hard as a winter nipple
I think the problem you were encountering, with the wandering and the oversize hole is caused by the cutting edges of the drill bit. Masonry bits are designed to be hammered into hard substrates like brick and concrete. So their 'leading edges' are not sharp. In fact they have another bevel ground onto what is normally the cutting edge of drill bits, to keep the leading edges of the carbide tip with a wide angle, which is able to withstand the hammering into concrete etc. In fact it IS POSSIBLE to sharpen these bits. If you think of a TCT router cutter, the edges have to be SHARP, in order to cut wood. And the carbide drill bits also have sharp cutting edges. So if you use a diamond file/wheel/plate to put some sharp edges on the masonry bit, it should act much more like a carbide drill bit. Not sure about the degradation of the tip though. Not tried a sharpened masonry bit in steel. Maybe you could give it a go???
It's an old time hack to use a masonry bit to drill hard steel, my dad taught me this many years ago. I actually used this to drill out a snapped exhaust stud on my Fireblade after a couple of attempts welding a nut on had failed and the stud had become so hard that regular HSS drills wouldn't touch it. You need to make sure the tip is actually sharp and you need to be careful not to get it hard enough to melt the braze that attaches the TC tip to the shank.
To stat a hole use a small bullnose grinding stone and create a small dent so the drill will follow in as when you do a center punch
What brand mason bit do you recommend ?!
Nice video
For those once in a while things where you need a hole and don't have the money to dump on the "right" drill, this is viable. You pointed this out in the video. A better this than nothing thing.
Use a green grinding stone or a diamond grinding wheel and give the carbide more of a "flat brass or plastic" style of edge with a keenly sharp edge and some clearance. They then bite in and cut pretty well for at least 4 to maybe 6 holes in HSS or hardened steel. Been there, done dat and got the holes in the low cost 123 blocks that now pass 3/8 bolts instead of not.
you should try one of those carbide bits for tile to see what it does. it seems like they have sharper points.
I was machining AR-50 plate, really tough steel. I had to drill 30 holes in a pattern. I was able to do it with masonry bits. I had to resharpen them a lot but it got the job done. I completely trashed 2 of them and the third one barely had anything left but it was about $20 VS. $100 or something and it didn't take me a ton longer to do it. Accurate holes? Nah, but they did what I needed to do.
Well, I am surprised. As pointed out, this type of bit is essentially a crushing bit for brittle materials. I assume the improved ductile drilling action came from the chips in the tip that probably are heat crack related. This makes me think that it is worthwhile grinding a conventional twist drill profile on one of these.
What if you ground a new bit in one of those precision grinders to give it cutting angles more closely resembling a normal twist drill.
Went it comes to masonry bits, they don't really cut rather than chisel. You should definitely sharpen them to have a similar cutting edge to a actual drill. As well, when cutting through hardened steel, do not use coolant.
I really should try putting one in my d-bit grinder and grind a proper geometry on one of these. Out of the box, the cutting edge looks like it's more of a rubbing edge, it definitely needs some clearance and a thinner edge.
Yep, set the proper geometry on the insert and it will run like a champ 👍
Bosch multiconstruction bits (the blue ones) come ready ground to drill plastics, steel and masonry.
After snapping a drill bit below the surface on a pilot hole in mild steel i used a masonary bit to drill out the broken drill bit
The carbide on those can be actually quite decent. The geometry on the tip is a mess tho for drilling proper holes in metal BUT you could grind, with a diamond wheel and (toxic) dust extraction please, a similar geometry on it then with a normal HSS or carbide drill. Works actually quite fine! In case you have a grinder lying around and no fitting drill bit for hard stuff imo definetly a legit "hack". Keep up the good stuff and im curious whats coming next. Peace!
Anyone know if you can use one of those jewellers faceting machines to grind precision facets on things like drill bits?
I'm guessing you can get diamond honing discs for those things since they are used to grind things like diamonds...
Check out the Bad Dog Tools Multi-Purpose drill bits. They specifically sell their "masonry" drill bit design for steel etc. with a lifetime resharpening guarentee.
used in toolmakers shops for drilling Carbide and hard stuf since they exist.They are cheap and easy to grind. No joke.Go to any workshop in germany in the screw busniess or working with hardend and Carbide material,they will have a box with regrinded masonry bits....That a trick 17,as we call in germany. Better is even to place the carbide tip inside the tip of a HSS drillbit.
Just cut an edge on the tip and it will work to get holes. Done it. Just make sure you use a belt sander and keep the drill cool with water or you will anneal the carbide tip and soften it. It works.
can you grind a better geometry onto the carbide tip? and use cutting fluid?
if you sharpen it with a diamond drill bit sharpener its much better or use something like a mr twister carbide tipped drill bit thats designed for drilling hard plate in safes and such
Like you point out, masonry drill bit geometry is wrong for cutting steel. Or wood. Or anything other than masonry or stone. However, it is quite possible to regrind a masonry bit so that it does cut steel. That's where the lifehack, such as it is, comes in. But you need to know how to grind a drill bit.
There are caveats however. It's very difficult to get any rake on the cutting edge, you're going to end up with a 0° cutting edge. And you have to grind away half of the carbide in order to get the cutting edge in the right place, so you end up with something that's quite fragile. But you can absolutely make a perfectly serviceable carbide tipped drill bit by regrinding masonry bits.
Use a diamon stone or wheel to re profile the tungsten bit I also use this on my lathe tools with tungsten to keep it sharp, with some wd40 , amazed at how fast you can remove the tungsten
I have drilled out of tap before with a small masonry bit high-speed drill lot of patience
I've got a question. I wanna be able to put 10 (or 12) mm tooling on my stock 4-way holder because there is a wider variety of cutting tools for 10 mm that you can get for cheap, so I'm planning on milling down one side 2 or 4 mm. Do you think it will impact the rigidity a whole lot? Also, I think it would make a decent video idea,since most people do not have the cash for a quick change or na ew full cross-slide setup like you have.
It is a common enough upgrade that i've seen it done a few times before. it might reduce rigidity a bit but nothing that would matter in the context of a mini lathe.
@@artisanmakes Thanks for the input. I don't get why they couldn't have just put a bit more meat on the bottom, dropped it, and added so shims with the lathe, it would make the holder way more versatile.
Masonry drill bits work great in Phosphor Bronze. Normal drills tend to jam but the side of the carbide can be sharpened too and it keeps cutting no matter how hot it gets. 😀
Would running the bits at a much higher speed prevent the bits jamming in phosphor bronze? And a slower feed rate too...
Have you tried "Multi Construction/material Drill Bits", basically Masonry bits ground to cut steel, rebar etc. already by the manufacturer?
i bought solid carbide drills to drill some tool steel using a good pillar drill,the quill does not match my lathe or mill for run out,and the bit shattered on contact with the work piece,lesson learned ,use the mill.
8mm solid carbide bit from ebay a few quid no big deal,just a pain in the arse.Next time i want to cut 65ish rockwell i'll sharpen a masonry bit.
i'd be curious if you could change the cutting geometry on the carbide, it kinda seems like you're mostly cutting on the web until the very end. Be interesting to fiddle with.
@0:30 - I am glad to see this is actually a running gag. It's painful but funny.
Isn't it customary to use coolant when using carbide? Also, I've heard many machinist recommend using oil and drilling slowly when drilling steel. I'm just a beginner, so sorry if I'm missing something obvious, here.
The best use i have seen in the real world for this technique is if you need to drill a hole through the bar of a chainsaw, such as for mounting a sawmill jig
Was it not possible to punch the metal to assist the drill starting? Also some coolant should prolong the life of the drill.
A tip, or two... Using these kinda demands of you to at least have a d-bit grinder, as to be able to impart any required geometry into the carbide tip... As was shown, you can push it through, but it would and could be self centering and easy cutting, if it had proper geometry imparted... Not just that, but keep in mind that despite this being carbide, it is brazed onto a steel body, so cooling is most critical if you want to allow it to cut some proper holes... The hammer drill bits with carbide, or cermet tips are much more durable than any lathe insert or mill insert or even carbide drill for that matter, as those are cooked as to allow them to impact hard into stone again and again, tens of throusands of times in their working life, without any problem or chipping, but they are not as appreciative of heat as some machine carbide is... You are unlikely to burn it up, but heat can fuck up the geometry imparted or mess with the braze joint, so keep them cool, and consider a dbit grinder... Also, if you can snag junked large sds hammer drills with carbide tips, those can be taken out with heat, and the carbide or cermet insert can be brazed back onto another say square shank, and allow you to grind a lathe tool from carbide that will be immensely better at dealing with interrupted cuts than any other regular insert you can get(that isnt the same grade carbide and costs an arm and a leg)... If you can get them as scrap, they are literally worth their weight in gold for custom tool making, and they are nearly cbn hard, so if you need them for hard turning or hard fly-cutting, oh boy, are you in for a treat like you`ve never seen before... Its a great material if you can get it as scrap, and madly pricey if you get them as a dedicated product from a supply... Just like with cbn or such, a few bits quickly add up...
Carbide-tipped steel drill bits. Amazon $15 for 5/16". McMaster here in the US. $16.95 for 8mm.
Most masonry bits are ground for punching stone, its best to resharpen the carbide to a shape that will better cut steel, that hole wouldn't have been as wobbly, and the bits seem to last longer when properly sharp.
There are carbide-tipped multi-material bits; I think I bought one and if I did I'll see if it's the same sort of animal with better geometry. I saw... Stefan? maybe drill through spring steel with slow feed and lots of pressure.
You need to sharpen the tip, then they are good in a pinch.
Alternatively look for locksmith drill bits. They already have the right cutting geometry.
Wow! Steep price! AU dollars?
I pay less than € 10 for an 8 mm tungsten carbide drill bit.
But, wait! This is not a 'normal' drill. It has canals built in for cooling fluid, hence it's high price tag.
You do need to grind the tip before drilling to a better geometry. Then it should work fine. My co workers do this sometimes
Re-sharpen the point to much more appropriate angles, cool it by blowing air on it. Also, get a shorter drill.
Used to do it in die-making workshops to get through hardened steel, all the time (well sometimes, ok occasionally...)