Oh, I see. Becasue of the continuous guiding of the Center Drill Combo with the Twist Drill, it prevents the twist drill from "chattering" or wandering thus enlarging the hole like a cone. Great technique. Thanks.

Interesting to watch, but when the final grinding was done by hand I fail to see the point of wasting all that time using the Lathe plus a Toolpost Grinder? Just learn to grind drills by hand. Yes it takes a lot of practice, and yes they will only rarely be truly accurate, but it's quick, it's very satisfying and the holes will usually be accurate enough for most normal purposes. In any case if you need a true and accurate hole you drill undersize and finish with a reamer.

Oh, so you basically ground a twist step drill? While I'd rather buy a set of them off the internet personally, I applaud your skills with making it.

Muy bueno, y muchas gracias.por mostrar esto maestro.

Interesting method! Thanks for posting and take care!

Nicely done. Too much of work though, especially when you need to regrind it later. I prefer center drill and normal drill separately. Thanks for sharing!

There is no need for this. Just check if the main cutting edges are the same on the Drill or the Drill is blunt... Refix this and all is good... Have a nice day and nö offence 😊

Хорошая работа.

Most drills do not have a thin web that is of consistent thickness along the drill. As the drill shortens, the web gets thicker so making an effective pilot is impossible. Good for a counterbore with predrilled pilot hole. Dressing the stones is PITA.

Thanks for sharing, have a like from me.

Never had thoses Problems. Get a nice Splitpoint and Grind it to 130°

muốn khoan chính xác tuyệt đối phải chế tạo loại mũi khoan như bạn đã làm.

Perfeito

Hopefully this will work for me and I can save my bets thank you so much

Should be using a spot drill, not a center drill.

Just use a smaller drill first and the final size second

I recognize that piece from the fly cutter build.

Would drilling a pilot hole with a smaller bit, then stepping up in size do the same thing?

that's really cool

great joy at work here cheers for insight

Great 👍

Great video. Would using intermediate drills not reduce the sloppy fit ?.

now do a test with a small pilot drill all the way throgh before the 13 mm drill (standard grind 118 deg) - bet that drills nearly as acurate as the fancy grind job - give it a try and let see

Se quebrar a ponta menor, trabalho perdido. Prefiro broca aproximada e acabamento com alargador...Mesmo assim é uma boa idéia...

Quá đẳng cấp👍👍👍

Excellent work ❤️

Thank you useful 👍

Мастер дыр!

Very good 👍 From channel art cnc

hay algo extraño en el minuto 9:19 .. Supuestamente se hizo un orificio con una mecha de centrar. Para continuar con la nueva mecha, pero sin embargo, cuando utiliza lubricante, este parce caer por el agujero que se hizo con la mecha de centrar... Y si esta es no traspasa el material, evidentemente, ¿como puede caer lubricante a traves?? there is something strange at minute 9:19.. Supposedly a hole was made with a centering wick. To continue with the new wick, but nevertheless, when you use lubricant, it seems to fall through the hole that was made with the centering wick... And if this does not go through the material, obviously, how can lubricant fall through? ??

Nice

Быстрее и точнее развернуть отверстие после сверления.

заводская заточка - брак!

Why center drill so much Drill close size if you need to ream

Es buena la técnica y la e probado pero un compañero de trabajo casi jubilado ya me enseñó a afilar las brocas o mechas para que perfore con mejor exactitud usando la mecha centro siempre. Lo malo de hacer una mecha de esta forma es que solo la podés usar para perforar pasantes o que no te moleste pasarte de medida con el centro que dejas en la mecha pero es buena muy buena

Nice video, keep it up, thanks for sharing it:)

first time the drill was out sharp

Amazing

不必把13MM鑽頭尖端磨製成中心鑽形狀這麼麻煩。祇要先用12MM鑽頭鑽一個孔後再用13MM鑽頭鑽一次保証個孔是標準13MM的孔。

This is an awesome video!! Im sure this method will come in handy

👏👏👍

What is the metal to be drilled???SS or high carbon steel.

Hello kita hadir nonton video👍

You are going to end up needing tenant surgery if You keep hitting wrenches like that !!!

I don't see the point to this. A hole that needs to be very accurate still has to be either reamed or helical milled with cutter-comp to fit. Otherwise just hurry and get er done without getting fancy.

Lebih presesi.👍👍

That seems like way to much to go threw. If a drill bit is sharpened correctly in the first place it shouldn't cut over size. But to each their own. Pretty cool trick. Thanks for sharing 👍

КАК ВАРИАНТ.

🤓👍👍👍💪

I also use similar technique for drill bits I use surface grinder to make these bits....

Klu saya akan gunakan 2 mata bor terpisah, karna akan mudah saat mengasah mata bornya nanti.

👍👍👍

fantasticooooooooooooo

🥰🥰🥰

Very interesting and helpful video, l will definitely have a go at reproducing your work. Regards Gary

Higher quality drill would do the same

❤❤😅

👍

I'll have to fashion a drill like that some day, it's a very useful design. As for the proof you show via your calipers that the before hole was over size and the after was not, I am not so sure you're showing what you think you're showing. If you're saying that by NOT using a drill that doesn't have a center drill built into it will be out & wander, that is simply false. For your old drill, your pilot hole may have been too small, so it didn't lead in properly. The drill could've been dull and was more so rubbing rather than cutting, The other explanation is that the legs of the drill before it was sharpened weren't equal lengths-- when one cutting edge is longer than the other, it will wander quite a bit, within the range you showed (anywhere from 5 to 15 thousandths). If you pilot drill properly, and have a well sharpened drill, then the hole will always come out perfect. Also there is the question of how accurate a drill should be. If it's simply clearance, it matters little. If it's for reaming, it matters quite a lot. If it's for a tap, that would depend on how critical the thread is, then you might need an exact minor diameter.

Did you not sharpen the full diameter flutes? Did I miss that step?

:)

Because the grinding of the original drill bit has no self-centering ability. Just use a small drill to drill a through hole first, and then use a big drill to solve it.😄

you can buy them been around for years in australia,called torpedo drills.

Waste of time and money. Twist drills are not made for precise holes. You need an undersize hole with a reamer for precision holes.

No hai palabras

Böyle makina olsa uğraşmam hazır alırım

Very very impressive!

Interesting but I feel not worth it. Cost of stones and time just buy new drill bit

Fake! Coolant drips evidence you snuck in a through hole after starting the centreing drill shot and before finishing it. That'll unload a drills centre web giving greater accuracy regardless of step grinding the drill. You fake the shot showing how little you think of viewers and gives me confidence to ratio your thumbs down and call on all viewing to do so.

Excelente

I don't think that I would frig around doing that

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