The best countersink drill bit in the world ? 

Note: These are apparently called Weldon type countersinks or cross hole countersinks. Cheers Rob

Why would you approach the work with the drill going like the clappers before it touches the wood? I have used all the types of bits that you demonstrated , all with fairly good results on wood but I would speed the drill up after contact, not before.

Got the same thru hole countersink and it worked like a champ when having to do 200 countersink m5 holes . Thank you so much for making this video! It save me bunch of time and money.

I need to buy these! I pass em every time and I haven't looked into it but now I know that's a tool I need.

I have been using this countersink since the 1970’s. They are Weldon countersinks available in 90* for metric flathead screws. In the US generally for deburring and pretapping countersink. US application 82* for a flathead screw which is standard for UNF screws. They are also available in piloted versions. Best countersink I have ever used especially for metal applications. Also very good on UHMW , phenolic and many plastics. Extra care should be taken when using on soft wood applications

Thanks. That confirms what I have found from experience. I got two HHS bits, of the better type, a while back and haven't looked back. Gonna have to figure out how to sharpen them though as watching this I realise that they don't cut as well as they used to.

Hi Rob. For years I used countersink bits like your old one. They work well but you really do have to get the speed right to avoid chatter. Then about a year ago I saw someone using those new ones with the hole on a RU-vid video (think it was Ade) so I thought I'd give them a try. Bought a 3 size set and they are all I use now, give a great finish on all materials, brilliant tools. Hopefully your video will introduce them to some more folk. Cheers, Alan.

Thanks Rob, hadn’t seen one being used before , look like a great bit to have 👍

Thanks for sharing! My cross hole countersink is a handy down from my father. I first noticed it in the 60's but it's possible that he made in mechinist class that he went through in the 50's.

I use the three cutter countersink bits with good results, a bit of cutting fluid helps.

Hey Rob. Thanks for the Demo. I have a set of zero flute counter sinks. I love them! Joe

Thanks Rob for a nice Demo Video. I bought a set of 4 of these from Victor Machinery Exchange, a USA Machinery Tool website a month ago. I went on the site to buy an unusual tap and die size that I needed for a project. The die wasn’t enough to meet their minimum order requirement; so, after looking around I bought a set of four “de-burring drill bits” to meet the minimum order. I haven’t tried them yet, but, after watching your video, I am sure glad that I did so. Cheers 🤠

G'day Rob and thanks for sharing buddy 👍I have the 4th one with 2 "flutes" in a set of sizes, all I use now

Hi Rob, I have used these cross hole deburring tools in the machineshop since the early seventies. Generally used for deburring holes as they don't have the tool life of the multi edge countersink bits for repetitive countersinking in steel, especially if working 350 grade boiler plate or higher grade steel alloys. The multi edge countersink tools need the work piece clamped rigidly on hole centre to work effectively, well that has been my experience working with these tools. Cheers, BADOLDBIKER.

Gday Rob, I have countersinks in both them types and I’m really impressed with the single flute type, I’m not sure of the exact name but they really work well, thanks for sharing these tools, Cheers

Good demonstration. Thanks for the look.

Just as a precaution as you can see in almost every instance here you cannot trust that your countersink bit will simply self centre You should take all precautions to centre it yourself in every axis, you can see the chamfers on at least 3 of those holes are not centre to the bore In order to counteract this the vice should be secured to a press table firstly, align your jobber up and then you should drill the hole, swap out the jobber for the countersink cutter and then countersink to your desired depth without moving the workpiece (a crank drill press table is very nice in this case as you can higher and lower the workpiece without moving it away from centre after you have made the bore) This ensures repeated centres between bits, I know this video was done as a quick comparison between countersink bits but if any newbies are watching this is the correct way to ensure your bit is cutting precisely.

The last one is ment for deburing but it's so smooth I prefer to use it for its not intended purpose

Hi Rob, good demo. They are cross hole c/sinks as I believe some of your other viewers have said. I made myself a set back in 1989 (still got them). I think I showed them in one of my very early videos (toolbox tour I think). They are good but only having the one cutting edge, they wear out much quicker. Cheers, Jon

Great demo video.

I think you're right about the process order. The only way you could accurately drill the countersink is on a milling machine. On a drill press, the counter sink is relying on the hole as a pilot to index the countersink in the right location. There's simply not enough rigidity

At least for the set I have, those cone shaped bits wear pretty fast in steel. They give me amazing results in aluminum/brass and some plastics. They stay centered and don’t chatter even in a hand drill.

Thanks for posting Rob. I’ve put my order in with Banggood to give one a try. Hope you’re ok. Regards. Chris.

I bought a small set of these about 2 years ago, and they would not cut butter they were so soft that I threw them in the trash. I've never seen the cobalt ones before, and looking at your results Rob, I'd buy one and give it a try.

Hello Rob, A nice well balanced review... Thank you... Cheers. Paul,,

Very impressive " 3 more tools to add to the collection " Thanks for sharing regards Sleepy

also the hole trough style you can self resharpen with next to no sharpening experience, just lay em flat on sandpaper and roll. for the inside hole get a dowel and sandpape and well you know the rest. stupidly easy and such a superior tool!

Rob, I think #2 in your lineup is getting short shrift because its well-worn. That style has worked well for me in wood for years. Even better is a similarly-shaped three-fluted design, but the only one I had is now useless, and I can't find them anymore. Never tried the cross-hole type, although I have one or two in my toolbox from job-lot purchases--Thanks for showing how well they actually work.

I've tried them all and wasn't impressed by their performance so I decided to go for the single cutter countersink and what a world of difference it made! Will never use any other style ever again.

Dont get too excited about them, I have had a set for many years and I find that if you dont stop and clean the hole out after each cut you will end up with an oval hole, I took them to the tip but they rejected them, so it is back to the old style rose cutter now. David

Come now Rob the wood test was grossly a bodge job, no one I know starts a drill if countersinking well above the hole and then tries to line it up. As for the Cross hole bits they are off centre and must be used in a machine chuck or you end up with of centre counter sink holes. Time you sharpened that old fluted bi too.

Ive had a set since the mid 70s they have been around for years,, where did you get the Eagle oil can ? Regards Frank

Great video, im sold! Just ordered from banggood for the first time.

Agree with your assessment, Rob. The cobalt single flutes are the best, but for all of the countersinks, have found that they produce less chatter/walking when run slower than the pilot drill (especially the Banggood Ti multi-flute type). The old HSS multiflutes only seem to work well brand new and dead sharp.

Best ones I've seen are the angled 6 flute ones, very expensive though.

With the course countersink (i.e. number 3) try running the drill in reverse to avoid the chatter, for wood anyway. never done it on metal.

Hi Rob. Not used the cross hole bits, but I do have a set of brand name (dormer) bits of a similar design to the other banggood bits that chattered for you. Mine don't chatter at all, despite being basically the same, my guess would be there's geometry issues on the bits you got. There's another type, specific to a given diameter of pilot drill, it's a one or 2 flute "classic" style countersink bit with the centre drilled out, and sat on a bit of drill rod. the only thing I've found that will give a decent countersink handheld, as it's piloted by the hole. I do have to echo the other comments about attacking a countersink in wood with the drill running full chat - that's not going to end well.

I found the countersink drill bit with the hole on ebay but it says it is not recommended to be used with a hand drill. Any comments about this?

There are 100 and 120 countersunk fasteners in aviation catalogs if you're in softer materials.

SAE countersink angle is 82 degrees…..metric is 90 degrees

Have you tried countersinking in Steel by hand?

These have been around for quite a while, I have a very old one floating around somewhere ;-) Yep, they work well, I wish I could find it, somewhere in storage, after 3 moves :-( Not sure why you 'plunge' the countersink, at speed, instead of placing it against the workpiece and turning it on while applying light pressure...that avoids that bouncing around you get when it's not right on centre as you 'plunge' the bit...only thinking.

How's the cutting pressure on that last one?

Drill bit the counter sink first in wood then the hole

i used the zero flute countersinks in the US of A 1980, it is not that new;

The fist one is for timber only the second one is a good all rounder but mainly for steel counter sinking The third one is made for deburing more than countersinking but will work for both just not ideal That why you wouldn’t see the cross hole version in you searching try searching for deburing bit not countersink

bugger, you must of sold a few of those M35's for them, out of stock when I had a look!

I have no dang idea why you are starting the drill up first before doing the countersink. That's just counter intuative. Talking about the hand drill.

That is called a "cross hole countersink" They've been around for a while and are easy to make in the workshop too unlike the other designs.

Hi rob are you in the south or north of SA

I've been using cross hole cs bits for a few years and they are so much better than more traditional cs bits. For your hand drill demo, your results are predictable because of the technique you used. I would always place the cs bit in the drilled hole before activating the drill when countersinking with a hand drill.

I don’t understand why you don’t set the bit in the hole before you press the trigger. It’s going to bounce back if you press the trigger without pressing it up against the wood…

Should have tried some aluminum as well.

1) 🙄put the drill in the hole first before drilling hit lol 7:51

I'm not a professional woodworker - but even in my experience you would never approach a piece of material with the drill going flat out to countersink a hole -does not make any sense and just asking for trouble

the ones you showed can be made to work but you left out the best countersink in the world. standard single flute and most common. Will do short video sometime today. The multiflutes the slightest wear you now have 3 or 4 flutes that start refusing to go in and they leave terrible burr. The one with the hole cant countersink small holes. The single flute will deburr a tiny hole perfectly all the way up to half inch or so. The others cannot be practically sharpened easy and have to thrown away after some use. The single flutes go almost forever and to sharpen a person can even do it by hand by grinding the rake face then you are good to go for another ten years. The single flute that come to a point you can also set the toolheight on a cnc and program them perfectly no need to check and adjust. The multiflute ones come to a terrible chopped off point cant be used on small holes.The one with hole worked well in perfect new situation with perfect size hole but generally they dull fast usually to be thrown away and no way to sharpen. The single flute I am talking about are the most common in the world at every home depot or anyplace used them for over 50 years and even in my core tools I have several in case I go to a shop where they dont have them.

I hate slotted screws/bolts, they have no room in this realm!

To be fair; - using a regular drill you don't put the machine at full-speed and then manually try tto hit the hole, you know beforehand that it will fail. - the second coutnersink looks old and dull, and made for metal. - same problem as the first, you seem deliberatly trying to make things difficult and then blaiming the tool :-) Not saying the fourth tool is no good, just blaming the operator for most of the failures of the others :-P

You are using way too many RPM's