left hand drills

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BaronJ

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Hi Guys,

I've a number of left hand drills, only really useful if you can turn them anti clockwise. They are very much a hangover from the multi spindle drilling machines, where alternate drills ran the opposite way due to the chain drive to them. They could also be positioned in different places in the drill head.

It reminds me of my younger days, when the foreman gave me a drill to sharpen ! I couldn't sharpen it at all ! I remember the other lads laughing at my struggles. At least till one put me wise. The crafty bugger had given me a left hand drill to sharpen...
 
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The left hand bits are often used as an aid to removing broken fasteners, since a slightly stuck bolt or screw might come out just due to the action of the left hand drill as it is being used to drill a hole in the fastener so that a screw extractor could be used.
Thanks Jim, I was pretty sure the rotation would be counter clockwise. I had tried to find the info on the web, the only info was what I already knew about drilling out a broken screw . Must have tried for 2 hours before posting here.
This is apparently a brand new set of drills. Neighbor lady found them in her dads shop. He had passed two years ago and most of his wood shop equipment went to the sons. I have a few friends that may be interested in some of the accessories left behind. Mostly hand tools and a shop built band saw.
mike
 

SmithDoor

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I recently was given a set of left hand drills. Which is the correct rotation , clockwise or counterclockwise?
thanks mike
They were used on screw machines They only had 2 clutch so for high speed ran backward forward was for tapping.

Today the work great for broken bolt the left drill sometimes brings out the bolt.

Dave
 

bluejets

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I have a left-hand shifter, had it since my first tool allowance.
No one wanted to pinch it as it used to screw with their head when they went to use it.o_O
 
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They work pretty well for removing broke bolts. Drill a hole in your bolt, put a left handed drill a couple sizes bigger in, and push hard. Hopefully it catches and breaks the bolt loose.
 
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When I was in grade 7 (circa 1961), I bought my first set of drills from the army/navy surplus store in London, Ontario.
I used some of my savings from a newspaper route. I made some wooden boats out of 2x4 scraps to float on the river. Then, imagine my shock & grief when I tried to drill a 1/4" hole in a piece of steel. The drill jammed at the bottom of the hole and the flutes straightened right out and partly reversed. That was my last experience with left handed drills.
The set must have been an early chinese import.
 

larryg

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They work pretty well for removing broke bolts. Drill a hole in your bolt, put a left handed drill a couple sizes bigger in, and push hard. Hopefully it catches and breaks the bolt loose.

Are you saying to pre-drill with a right handed bit and then use a left handed one? I always start the process with a left handed bit.

lg
no neat sig line
 
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Are you saying to pre-drill with a right handed bit and then use a left handed one? I always start the process with a left handed bit.

lg
no neat sig line

Ideally you'd use a left handed to drill the through hole, but we use a lot of grade 8 bolts at work and you end up burning up hss bits if you try to drill a through hole with one. So If the bolt doesn't spin out with a left handed center drill I'll switch to a carbide drill to do the through hole and back to the hss left handed drill to try to spin it out.

Keep in mind that a work environment is different than home. When a piece of equipment is down it's cheaper for me to risk destroying a bit if my bolt spins than it is for me to run back to the shop to resharpen a bit multiple times.
 
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aka9950202

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Also known as a all 16th in some circles.

Cheers,

Andrew in Melbourne
 

goldstar31

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Oh come on, this left hand business goes back in Heraldry of 'Dexter' and 'Sinister' on the Shields.
The most ancient one of 'left handed' is the Patron Saint of Nortumblria who brought Christianity to our shores. There was and still is the Holy Island of Lindisfarne and his Farne Islands which are bird and seal sanctuaries - a chain off 3 miles from North Sunderland Seahouses.
Eider ducks breed there and are locally known as "Cuddy's Ducks'. His abbreviated name 'cuddy' is al;so attributed to expressions like Cuddy Handed for left handers and breeding between horses and asses( not as a mule.

In Shakespeare's play Richard the Third, the local joke is
A Horse, a horse, my Kingdom for a horse'
and the local wit from the gallery shouts
'Will a cuddy do?'
and the classic reply is

Come around to the stage door at the end of the play!
 
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larryg

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Ideally you'd use a left handed to drill the through hole, but we use a lot of grade 8 bolts at work and you end up burning up hss bits if you try to drill a through hole with one. So If the bolt doesn't spin out with a left handed center drill I'll switch to a carbide drill to do the through hole and back to the hss left handed drill to try to spin it out.

Keep in mind that a work environment is different than home. When a piece of equipment is down it's cheaper for me to risk destroying a bit if my bolt spins than it is for me to run back to the shop to resharpen a bit multiple times.

Ok then. I also come from a manufacturing environment and know when down time is calculated in $xx/second that sacrificing a tool bit is a cheap fix if it works.

lg
no neat sig line
 

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