It doesn’t always go the way you wanted

[Speedy Builder5Participant @speedybuilder5]

Bad day in the workshop! Busted my 1 1/32″ drill, and the insert tool I was using to put a short round end on the morse taper end. I have had and used the drill for more than 50 years – You don’t win every day though!

[Robert Atkinson 2Participant @robertatkinson2]

Looks like a classic low cycle fatigue failure. You can see the beach marks.  I’m sure it wasn’t designed to last 50 years. 🙂

Robert.

 

[Speedy Builder5Participant @speedybuilder5]

Looks like a classic idiot mistake – tried to hold the point end of the drill in the chuck, morse end supported by a centre.  started to turn a parallel section at the morse ens (interrupted cut on the tang) and suddenly bang!  Just as the tool dug in, the drill bit wobbled in the 3 jaw chuck and I was lucky not to get hit by the shrapnel.

Perhaps I should have machined a bit of thick wall tube with a longitudinal split in it and then used that to hold the drill ?

[SillyOldDufferModerator @sillyoldduffer]

The photo does look like fatigue failure, hardly surprising in a 50 year old drill.  Each time a twist drill is used the helix is stressed and cracks grow from microscopic flaws in the metal caused by impurities, heat-treatment or external damage.  Well made drills should last longer than poor ones, but nothing is perfect.

Machining the poor thing with that setup was pretty brutal, but I guess it just exposed an existing flaw.  I’ve made a mental note to grip  drills in a tube if I ever need to machine one!

Dave

 

 

[Brian WoodParticipant @brianwood45127]

Holding the drill body in a split collet made for the job would have been the way to go. To replace that exact size will be difficult now; the nearest metric ‘equivalent’ is 26 mm which is 0.2 mm undersize on diameter.

Reshaping the end will leave it short but at least it will the right size.

Brian

[old martParticipant @oldmart]

Just grind a bit off of it every week and it will soon be ready to be finish ground without boring you to tears.

The split collet method, mentioned, for holding it together with the centre in the tang would be the best way to make it into a large blacksmiths drill.The longer the collet the better for the drill to be supported evenly.

[Brian Wood]

On Brian Wood Said:

Holding the drill body in a split collet made for the job would have been the way to go. To replace that exact size will be difficult now; the nearest metric ‘equivalent’ is 26 mm which is 0.2 mm undersize on diameter.

Reshaping the end will leave it short but at least it will the right size.

Brian

Hi, I don’t see why, but it might damage your wallet a bit.

https://www.ukdrills.com/morse-taper-imperial-bit

Regards Nick.

[larry phelan 1Participant @larryphelan1]

Only lasted 50 years ?

I think you should bring it back for a refund.

[Nigel Graham 2Participant @nigelgraham2]

For a drill that big, I think I’d remove the broken portion first by cutting-disc in an angle-grinder. Maybe take a bit off each side too, with it, to approach the conical shape.

Then use the bench-grinder to finish to shape.

Not the bench-grinder completely.

That way reduces both wear on the grinder, and the time taken.

[Ady1Participant @ady1]

Looks fine to me 🙂

A careful sharpen could actually keep it going, worth a go

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