just to settle an old argument

[Migmac]

None, keyless chuck!

 

[piman]

Hello all,

I've tightened one only on a drill or a lathe, done so for decades.

Chris "the jaws are operated by engaging with a thread individually so would definitely benefit from tightening all round.",
if you mean independant jaws as most four jaw chucks are, then yes.

Alec

 

[ukracer]

Hope fully a genious will come along and tell us the real scientific reason. @Maker

I use just one......... but if I think it might slip or its a big drill I use all three.

I do feel it works as it rarely spins after I use all 3....

 

[Maker]

I only use one, on a drill or a lathe. Whichever you use you will turn the same scroll which will tighten all three jaws evenly, wouldn't it?
I had always thought there were three holes for convenience but possibly also because it would also be better balanced with three holes rather than just one.

I had noticed Doubleboost do it in a few videos and had wondered why.

 

[rtbcomp]

I use all three progressively. Although they all turn the same ring if there's lateral play due to wear in the ring it could cause the jaws to tighten off-centre if you use one hole.

 

[xmetal]

I use all three progressively.

That's what I do.

 

[the snooper]

Always more then 1 and you always get a bit more on the hole which must be due to uneven forces between the collar and jaws even in a new chuck there is slight play

 

[mike os]

One for small drills or if the chuck is good... 2 or 3 for bigger bits or materials likely to snag or if it slips

 

[rtbcomp]

...
I had always thought there were three holes for convenience but possibly also because it would also be better balanced with three holes rather than just one.

...

Two holes would balance OK and be cheaper, I don't think it's coincidence that there's one hole per jaw.

 

[Newlands]

Which ever hole you use (erm), only turns the same toothed ring though.

Exactly. Even if the chuck is worn only one is necessary, for two reasons - the first is that the scroll or ring is operating on all three jaws together, and the second is that any one of the three jaws is exerting pressure on the other two. It is impossible for one jaw to exert more pressure than any of the others (opposing forces and all that). It might be possible on a worn chuck that the drill (or workpiece on a lathe) will not be exactly centred, but how many of you clock a drill after you've chucked it? And on a lathe, if you want to centre something accurately you use a 4 jaw.

 

[The_Yellow_Ardvark]

Way back in the mist of time, working for Noah and Sons.
It was drilled into me.
Lathes tighten up on all, it saves wear and tear. Plus on a 4 jaw chuck you are all ready in the habit.

Drills, if Jacob style use 2, again to save wear and tear.

Brace and Bits and wood working tools, hand tight only.

But to be honest on drills one hole for speed.
But last time on a lathe, after a few minutes old habits came back

 

[fixerupper]

Yep on a lathe or a drill press I go round all the holes, on my old big heavy hand drill I tend to as well 'cos the chuck has seen better days and it need s the extra to hold the bit ..... it just how I was taught .....jeff

 

[rtbcomp]

'
...Brace and Bits and wood working tools, hand tight only.

...

In a brace & bit the turning force is transmitted through the square end of the bit via a square hole in the chuck, so it just has to be tight enough to stop the bit falling out.

On my Progress No2 drill you have to turn the chuck in the opposite direction to rotation to take the backlash out of the clutch, so you might as well use all three holes at the same time.

 

[roofman]

3 for me on my lathe..puts an even load on the scroll and jaws.

 

[julianthegypsy]

I was taught to use all three in college, many aeons ago, and I still use at least two. It does tighten up on the second one too, even when I've got the first as tight as it will go.

 

[Mr shiney]

What's a chuck key? Mine are all keyless chucks......

 

[Bill Edwards]

Exactly. Even if the chuck is worn only one is necessary, for two reasons - the first is that the scroll or ring is operating on all three jaws together, and the second is that any one of the three jaws is exerting pressure on the other two. It is impossible for one jaw to exert more pressure than any of the others (opposing forces and all that). It might be possible on a worn chuck that the drill (or workpiece on a lathe) will not be exactly centred, but how many of you clock a drill after you've chucked it? And on a lathe, if you want to centre something accurately you use a 4 jaw.

No, it doesn't work like this on drill chucks.
I can't explain why but I can tell you that if you tighten the first hole as tight as you like then the second one will turn it a little further for the same amount of force.

So you can use one if the chuck grips well but if you need it tighter you do need to use two or three. They're not there for decoration.

 

[brightspark]

do we need to do a test on the tightening of drill chucks using a torque wrench on all 3 holes to prove the point

 

[Freddy0309]

do we need to do a test on the tightening of drill chucks using a torque wrench on all 3 holes to prove the point

Could be a job for doubleboost for the next Sunday night night cap

 

[the snooper]

Could be a job for doubleboost for the next Sunday night night cap

See how tight it can hold a spring onion