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ps_bond
18-02-2010, 09:53 AM
You know what it's like when you are piercing something complex and you manage to break the last of your smaller drillbits? In the evening? On a Sunday? This may help...

Take a sewing needle. Chunkier is slightly better, but it has to be a nicely springy one (so some of my very soft harness needles are utterly useless for this). Using pliers, snap the eye in half. Grind the end flush on a fine oilstone; holding the needle at around 15-20 degrees, grind a flat to fractionally over halfway through the needle at the eye end. Then turn it over and grind 2 facets at about 45 degrees to make a sharp point.

Bung the needle - sorry, artisan crafted drillbit - in your bowdrill and drill away, leaving holes just big enough to fit a fine sawblade. I've gone through about 1.6mm sheet using one of these; I have to confess I haven't tried it with the Foredom.

There's other methods to make drillbits that are easy too - this one is just so quick & simple that it is something of a no-brainer.

mizgeorge
18-02-2010, 09:56 AM
great tip Peter :)

ps_bond
18-02-2010, 09:58 AM
It makes sense then as written? Wondered if the form of the point needs an illustration too.

lorraineflee
18-02-2010, 11:08 AM
If you could put an illustration on too I think it would help me!
Cheers
Lorraine

Di Sandland
18-02-2010, 11:29 AM
I understand completely - and thank you, you're a mine of info.

ps_bond
18-02-2010, 12:15 PM
If you could put an illustration on too I think it would help me!


OK, working on it. Nothing really suitable for it here at work...

daisychain
18-02-2010, 10:25 PM
Thanks for the tip! I tend to buy drill bits in packs of ten of the most common sizes I use as I either don't break one for weeks on end or break my last five within one afternoon, just when I've got something urgent to finish!

Green Beetle
19-02-2010, 12:50 PM
If you could put an illustration on too I think it would help me!
Cheers
Lorraine

Would help me too - sounds a great tip!

Thanks

ps_bond
19-02-2010, 01:06 PM
Haven't had a chance to draw something properly, so I've done a quick scribble -
http://www.cooksongold.com/forum/members/ps_bond-albums-peter-s-miscellanea-picture649-needle-drillbit.jpg

lorraineflee
19-02-2010, 01:29 PM
Thanks Peter, that does help - I was being thicker than usual!!
Lorraine

caroleallen
19-02-2010, 06:53 PM
Blimey, that sounds like hard work. I think I'd just wait till the shops were open!

Emerald
19-02-2010, 08:24 PM
lol or even sharpen the broken drill bit!