Long drill bit/ drill extension

[Norsk]

I need to open up and existing hole by 1mm. The hole is only about 10mm deep but in an awkward place. I therefore need a drill bit that is 70mm long or a drill extension that I can attach a hex drill but into.

Everyone I speak to here in Norway looks at me like I am stupid. Surely such a thing exists?

I can once remember seeing a hex shank with a mini chuck on the end that was for this purpose. Could anyone be so kind as to tell me what that's called?

Thank you

 

[voipio]

There are plenty of 1/4" hex extensions around e.g:

https://www.amazon.co.uk/Electric-Screwdriver-Extension-Magnetic-Handheld/dp/B0CD227KTB

Also, this kind of thing:

https://www.amazon.co.uk/Extension-Forstner-Furniture-Carpentry-Construction/dp/B09FK347GZ

All the types of drill extension I've seen recently, with chucks attached, have been the flexible type, and would struggle with 10mm drills.

 

[Norsk]

It's a 2.5mm diameter drill,enlarging a 1.5 mm hole in a tricky place.

 

[Norsk]

Thanks for the links

 

[voipio]

A possible alternative might be to use a pin vice. Something like a Starrett S162C will give about 80mm extension. The Starrett sets are going for silly money at the moment. The end of the handle will fit into an ordinary drill chuck OK, as it's 6.6mm OD on the Starrett part.

 

[hotponyshoes]

2.5mm x 95mm long drill bits are available easily enough

 

[Nomad]

I have some Hex extension pieces in various lengths that work well when I need them.
Also a set of hex-shanked drill bits, together they would do what you want - as long as you can find a drill bit the right size.

See the links above, I had one same as the 2nd photo (bit held with allen keys) and cut it up as it didn't hold the bit centrally or securely, it's now used as a long drift - handy but no use as an extension. Best avoided.

My choice would be an extension with a locking chuck so the drill bit doesn't drop out at the bottom of the hole, some are only hold the bits with magnets or an internal circlip... sample https://cdn-tp3.mozu.com/24645-3713...0eda2?max=250&quality=80&_mzcb=_1703879152693

 

[carbonarc]

 

[Norsk]

2.5mm x 95mm long drill bits are available easily enough

In the UK I bet that's nice.


I live in a town of 250,000 on Norways west coast on about the same lattidue as the Shetlands.

 

[Blobber]

Are you in a rush, can we get those drills above and send them over?

 

[julianf]

If you have access to a suitable lathe, you may consider friction welding a hss bit onto the end of a rod.

 

[dave h 2]

I have some Hex extension pieces in various lengths that work well when I need them.
Also a set of hex-shanked drill bits, together they would do what you want - as long as you can find a drill bit the right size.

See the links above, I had one same as the 2nd photo (bit held with allen keys) and cut it up as it didn't hold the bit centrally or securely, it's now used as a long drift - handy but no use as an extension. Best avoided.

My choice would be an extension with a locking chuck so the drill bit doesn't drop out at the bottom of the hole, some are only hold the bits with magnets or an internal circlip... sample https://cdn-tp3.mozu.com/24645-3713...0eda2?max=250&quality=80&_mzcb=_1703879152693

It would hold a drill centrally that was the same size as the hole, any smaller drills will be pushed off center

 

[northwest]

Stick the long extension in the lathe, cut the adapter bit off and counterbore the shaft, stick the drill bit in with some bearing fit and let it set, then off you go.

 

[carbonarc]

Another possible solution?

 

[Beanwood]

It would hold a drill centrally that was the same size as the hole, any smaller drills will be pushed off center

He mentioned they are hex drill bits so shouldn’t be a problem

 

[Barking Mat]

I just welded a length of threaded bar onto a drill bit I needed to extend.

 

[brightspark]

its a welding forum just weld an extension bit of rod to one i do it with masonary drills make them about 3 foot long

 

[Jelly_Sheffield]

Given it's a small, shallow hole, you're not taking much off, and you're trying to find a right now solution...

Could you just hold the drill in an MT drill chuck, or a chuck removed from drill, and turn the chuck by hand?

It's a slow process, and you might want to go 2mm then 2.5mm, but compared to waiting for something to turn up in the post, or driving to the hardware store, it's still very fast.

It's a trick that has got me out of some tight spots before.

 

[Farside]

Last long drill bits I needed to just nip past a frame downtube and drill out a broken exhaust bolt, I got from Tracy Tools.
Best of luck finding them, but they definitely have them.

DRILLS HSS - Taps & Dies, Reamers, Milling Cutters, Tracy Tools

www.tracytools.com

 

[Ruffian]

Tig and a bit of m6 threaded bar got this one able to go through the cavity for the pilot holes.