Tightening a keyed chuck...

[MR2FC]

Hi, I've been watching some pillar drill videos for purchase research purposes, and noticed some of them tighten a bit in the drill by using the chuck key in all three holes. One guy even said how important it was not to forget to do that...

It's been over 35yrs since I last used a pillar drill, but I don't remember my teachers telling me this, or my father (an engineer of sorts) when using keyed drills at home, I wondered what your thoughts were?

Thanks in advance

 

[Jack_K]

I read it recently too and have now done it a couple of times and there was a bit further I could tighten it using the other two holes. Whether it actually makes much difference I don't know but it does make sense.

 

[davethorik]

I was taught to use all 3 holes to tighten the chuck. Like Jack said, idk how much of a difference it makes in reality. Just how I do it.

 

[Fred W B]

I do all three holes all the time, i find it holds the drill tighter, particularly in larger sizes. But then my chuck might be a bit worn

 

[kmacht]

With the way a chuck is designed it mechanically doesn’t matter if you use one or three. Removing and reinserting the key to make take a second try at tightening the chuck will make more of a difference than using a different hole.

 

[captaindiode]

We were taught to use all three in my machine shop class back in college.

 

[RoninB4]

JMO from decades of machine shop work, never made a habit of tightening all 3 locations. If the drill spins in the chuck you're either:
1) Feeding it too fast and it's grabbing in the material
2) Don't have an edge break (if drilling brass) and is grabbing the material
3) Need flats on the shank for a more positive mechanical drive
4) Have a chuck that's been over-tightened and is "sprung" (need to rebuild/replace the chuck)
2) Are just using the wrong machine for what you're doing.

Tightening all 3 locations shouldn't create hole that's more true to size, whether by drill or reamer. There's several reasons for an over-size hole with a drill/reamer.

 

[RonnieC]

I just use one. I’ve met some people who thought that somehow each hole was magically attached to one jaw rather than just providing a fulcrum point to apply torque via the key.
Could it be that due to internal loose tolerances that by tightening via one spot you force the internals laterally and it’s a bit off center? Maybe in a loose or worn chuck I suppose.

 

[jack stand]

I do all three holes all the time, i find it holds the drill tighter, particularly in larger sizes. But then my chuck might be a bit worn

I do also.
But I remember that clothes pinning playing cards on to my bicycle so they'd slap the spokes added supernatural power to my bike.

 

[niget2002]

I don't and never would have thought to use all 3 until reading this.

 

[Viper98912]

I've only used 1 here...

I guess theoretically if your chuck was worn out, it could help (as previously stated above)

 

[Leaflessshadetree]

If the key slips move to another hole. It will get a better bite and a little more leverage.

 

[racecougar]

I have always tightened via one hole; never heard of anyone going around and tightening via all three. Do you loosen via all three, too?

 

[CraigStu]

To me that would be a colossal pain in the ****. The actual tightening of the chuck is done by the collar moving the three internal pieces. I don't see how turning that collar from one hole is any different from turning it from another hole. Now, if one hole is worn out, then going to another hole could be better but I suspect that all the holes are probably worn about equally. Maybe 2 years ago I came across an extra chuck key for my old drill press. That just slightly used key definitely did help reduce key slipping. I also make it a practice to orient the key so I am pulling it toward the collar to help w/ engagement.

 

[Walkers]

In the world of people who use keyed chucks there there are ‘One Holers’ and ’Three Holers’, which one are you?!?

 

[Grimpala]

In the world of people who use keyed chucks there there are ‘One Holers’ and ’Three Holers’, which one are you?!?

I guess I'm the odd man out, I'll tighten one hole well, then move to the next hole counter clockwise and give it a snug, then let 'er eat.

 

[Jarwop]

Why else would there be three holes?

 

[Lassen Forge]

I remember this... IDK if it was the teachers thing or what, but I was told (and have to this day, 40 years on) snugged all 3 (or 4) chuck holes... and everything has always stayed in place while machining.

 

[svhamelly]

In the world of people who use keyed chucks there there are ‘One Holers’ and ’Three Holers’, which one are you?!?

Two Holer!

 

[WillyBoy]

I guess I'm the odd man out, I'll tighten one hole well, then move to the next hole counter clockwise and give it a snug, then let 'er eat.

This is what I do. For years, actually decades, I would tighten only one hole because, after all, they're all geared together. Last year I decided to check the tightness after "one hole". I found that after tightening the first hole to where the key wouldn't move any further, putting the key in the next hole and twisting a little more, I could get another 5 - 8 degrees of movement. Now I know it's tight.
No, I'm not throwing the chuck away.

Maybe it's just me but I think there are three holes so the spindle doesn't have to be rotated so far to find a place to insert the key. About one time in ten, the spindle doesn't have to be rotated at all.

 

[Grimpala]

On a lathe chuck I would always tighten all the key holes, regardless of number. I've carried that over the to the drill press to some extent.

 

[Garcky]

Whichever method you use, do NOT leave the key in the chuck, or the shop teacher, Mr. Hardassy, will whack you with something.

 

[svhamelly]

Whichever method you use, do NOT leave the key in the chuck, or the shop teacher, Mr. Hardassy, will whack you with something.

Shop teachers... Mr. Sherry and Mr. Bollard would also give you a good whack with whatever was in their hand or nearby for this type behavior

 

[Grimpala]

Whichever method you use, do NOT leave the key in the chuck, or the shop teacher, Mr. Hardassy, will whack you with something.

Saw a guy take a three jaw chuck key to the family jewels in HS shop one time. He was not well afterwards.

 

[Zeke]

Why else would there be three holes?

So you can locate a hole more quickly. I have a couple of 3-jaw one hole lathe chucks and it's a PITA to find the hole. Of course I could mark the face but I didn't think about that until this moment. That's my reasoning.

 

[4xdog]

Single-spot tightening here.

 

[P51Mustang]

Way, way back in high school my shop teacher said to always use all three holes when tightening the chuck. He said that it was to even the wear out on the chuck. I have no idea if this does help but even after a lot of years I still tend to do that.

 

[niget2002]

Why else would there be three holes?

So you can hit whichever one is closest without having to spin the darn chuck for 15 minutes looking for the hole. I guess if the room is well lit, the hole might be easier to find, but some of our workspaces are like a small dungeon with poor lighting.

 

[kmacht]

So you can hit whichever one is closest without having to spin the darn chuck for 15 minutes looking for the hole. I guess if the room is well lit, the hole might be easier to find, but some of our workspaces are like a small dungeon with poor lighting.

On some machines like a lathe the chuck stays fixed and the part turns. Having 3 holes makes it more likely to have one of the holes pointing in a direction that is reachable by the key without having to remove and reposition the chuck.

 

[58Yeoman]

Wow! Earth shattering first world problem. Use one, two or all three. Geez. I've got a real problem here for you all to figure out: Do you walk to work or carry your lunch?




No wrong answer here.

 

[dfiler2]

I was always told to use all three and I still commonly use two because you can always tighten it a little more on the second hole.

 

[alfadan]

Why else would there be three holes?

So you can locate a hole more quickly

<SNORT!>

 

[Barnabas]

I was a high school shop teacher starting in the 1980’s, and this is the first time I ever heard of this. None of my shop teachers ever mentioned tightening three holes, and I never taught that.

It is important for the Chuck to be tight, so figure out what that means for your Chuck.

I like the modern Chuck keys that are spring loaded, so you don’t accidentally leave the key in the Chuck.

 

[no704]

I was a high school shop teacher starting in the 1980’s, and this is the first time I ever heard of this. None of my shop teachers ever mentioned tightening three holes, and I never taught that.

It is important for the Chuck to be tight, so figure out what that means for your Chuck.

I like the modern Chuck keys that are spring loaded, so you don’t accidentally leave the key in the Chuck.

I hate you and anyone else that puts springs on chucks! Lol. Not really, but they ****!

 

[The Cobbler]

I've seen people do it, never really tried it myself.
There was a you tube video on 3 jaw lathe chucks, and the guy gave a reason for doing it on them. it made sense at the time

 

[Zeke]

I hate you and anyone else that puts springs on chucks! Lol. Not really, but they ****!

They **** so bad that I classify them the same as the new gas cans. Nanny state ****.

 

[MR2FC]

Thank you for all the replies

 

[MR2FC]

<SNORT!>

...especially this one!

 

[P51Mustang]

I was a high school shop teacher starting in the 1980’s, and this is the first time I ever heard of this. None of my shop teachers ever mentioned tightening three holes, and I never taught that.

It is important for the Chuck to be tight, so figure out what that means for your Chuck.

I like the modern Chuck keys that are spring loaded, so you don’t accidentally leave the key in the Chuck.

I have no idea where my high shop teacher came up with this but that is what he told us. This was auto shop and my teacher had worked for several years as a mechanic before becoming a teacher, so maybe this came keeping his tools in the best shape when he was making his living with them. He was a great auto shop teacher. He was one of the reasons that I went into engineering. I do not think this would have made any difference but this was in the early 70's.

 

[nadogail]

Usually it only takes one time for a new guy to learn to remove the key from a chuck before starting a Drill Press.