# Locking Chuck Key Idea



## ih8beingold (Aug 23, 2015)

My lathe has a chuck guard that gets in the way when setting up a four jaw. The solution is low profile chuck keys. I discovered that socket wrench extensions (3/8" in my case) fit and the little retainer ball KEEPS THEM FROM FALLING OUT when rotating the chuck. Probably not news to some but I didn't know. Picked up some cheap 3/8 x 6" extensions for a dollar and change. I imagine 1/4 would fit 1/4" square chuck adjusters as well. Cut to length and weld on a T handle made from the leftovers or maybe just knurl the ends on short one. Just be VERY careful. They could be easy to forget before you fire up the lathe.  Hope this helps somebody out.


----------



## hman (Aug 24, 2015)

I just got through making a set of low profile chuck keys for the 4-jaw chuck on my Grizzly 12x24 lathe.  The original chuck key measured 10mm, so I bought some 10mm key stock.  I'll bet your idea would have been even easier, as 3/8" is just under 10mm!


PS - that's not rust on the chuck.  It's just old (oxidized?) Cosmolene.  There's bright metal underneath it, I promise!


----------



## jpfabricator (Aug 24, 2015)

The first rule in my shop is " If the chuck key is not in your hand its in the holder." Even if using a 4 jaw chuck, the key is never left in the chuck. 

Sent from somewhere in East Texas Jake Parker


----------



## ih8beingold (Aug 26, 2015)

jpfabricator said:


> The first rule in my shop is " If the chuck key is not in your hand its in the holder." Even if using a 4 jaw chuck, the key is never left in the chuck.
> 
> Sent from somewhere in East Texas Jake Parker


Excellent point but I want these to stay in the chuck when I rotate it. A necessary evil in this case. I promise to be careful. Perhaps a special holder to keep them in so one could quickly see if one was still in the chuck obscured from site. Like counting sponges after an operation.


----------



## ogberi (Aug 26, 2015)

My two chuck keys live in a pair of screwdriver holders on the wall mounted pegboard behind the lathe.  I have made myself get in the habit of looking to see they are both there before rotating the chuck by hand, and again before turning on the lathe.  If I don't see them, I stop everything and find the offendingitem. put it in it's home, then start over by rotating the chuck by hand.  

It's automatic habit now, I just drop the keys back into their holders.


----------



## RJSakowski (Aug 26, 2015)

Perhaps a useful mod would be to make a chuck key holder with an interlock switch so the lathe can't be powered up unless the chuck key is stowed.

Bob


----------



## chips&more (Aug 26, 2015)

The new chucks that I have bought recently came with a spring on the chuck key so you cannot leave it in the chuck. The spring makes sure of that. It’s also very annoying and the springs are now in my spring collection draw. Maybe they will serve some useful purpose somewhere else in the shop. As far as some shop rules that I can recall from back in the day. Wear your safety glasses and your steel toed shoes and never leave the chuck key in the chuck. Makes perfect sense when you think about the consequences of say getting hit in the mouth and losing a few teeth. The chuck key in my shop is in the storage hanger, in my hand or in the chuck with my hand on it and never left unattended in the chuck…Good Luck, Dave.


----------



## GarageGuy (Aug 28, 2015)

jpfabricator said:


> The first rule in my shop is " If the chuck key is not in your hand its in the holder." Even if using a 4 jaw chuck, the key is never left in the chuck.



:+1:  I agree 100%.  The chuck key never leaves my hand when it is in the chuck.  Not even for a moment.  

Learning safe procedures and habits is the most important thing when working with machines.  Then, don't deviate from those procedures.

GG


----------



## Terrywerm (Aug 28, 2015)

Years ago I had a machine shop instructor that taught me a simple trick: After mounting something in the chuck, rotate the chuck by hand at least one full revolution. This ensures that the chuck key is removed and also that the jaws and the work piece will not contact anything else on the machine. I've done it that way ever since and never had any surprises.


----------



## mike837go (Aug 28, 2015)

My new lathe's chuck key spring is in the drawer marked "Springs".

Leaving a key in lathe, mill or drill chuck is just WRONG in my mind. My hands come away from the chuck because the bit or workpiece is locked in. The key is in my hand. Period.

There was an article in Popular Mechanics back in the 1970's. How to build a chuck key holder with a switch so that the key had to be properly seated in the holder before the drill press could operate. Safe? YES. Annoying? You better believe it!

On my handheld electric drills, I used to tape the chuck keys to the cord near the plug, so I had to unplug the drill to change bits. Again safe (unless using an extension cord) and very annoying. My newest drill has the key in a holder just below the grip and keeps getting 'lost' during projects. My favorite is on a 6" rubber lanyard in the middle of the cord. Inherently, the least safe.


----------



## RJSakowski (Aug 28, 2015)

I see little difference in having a designated location for a chuck key and having a holder with an interlock switch to prevent operation of the lathe with a key in the chuck.  One additional feature is if you are working around the chuck, having the interlock provides extra security.  My Grizzly lathe is fairly safe with its switches up high on the headstock and having to rotate the switch to the forward or reverse position but my Atlas/Craftsman 6" has a lever on the reversing drum switch that is mounted at hip height and could easily be activated accidentally.

I try to make it a practice to never leave the key in the chuck but I have to confess that I have done so.  It usually happens when I am removing something from the chuck and am engrossed in thought and forget to remove it.  When I look over and see it there, I pull it out and stow it but for the time it is there , a dangerous condition exists.  Requiring the proper storage of the key to prevent activation would eliminate that danger.

With growing concern over industrial safety, LOTO (lock out tag out) procedures have become common.  I have had to write a few procedures myself.  They are intentionally redundant and many times a pain to use.  Their purpose is clear, however.  Just putting a warning in a user manual to disconnect a machine from power or training personnel in safety procedures is not sufficient to ensure accident prevention.  People get distracted and accidents can happen.  

Just my 2 cents.

Bob


----------



## Fabrickator (Aug 28, 2015)

terrywerm said:


> Years ago I had a machine shop instructor that taught me a simple trick: After mounting something in the chuck, rotate the chuck by hand at least one full revolution. This ensures that the chuck key is removed and also that the jaws and the work piece will not contact anything else on the machine. I've done it that way ever since and never had any surprises.



This is what I do too.  Old School trick I also learned from a master machinist with two eyes and all of his teeth and fingers...


----------



## atunguyd (Aug 29, 2015)

Question :

Is leaving the key in the chuck add dangerous on new lathes add it is on the older ones? Most new lathes have done sorry if electronic speed control which normally has a soft start. So the slower spin up of a chuck means that the key will be thrown but probably a lot softer then on a lath with a hard start. 

Sent from my GT-I9505 using Tapatalk


----------



## jpfabricator (Aug 29, 2015)

atunguyd said:


> Question :
> 
> Is leaving the key in the chuck add dangerous on new lathes add it is on the older ones? Most new lathes have done sorry if electronic speed control which normally has a soft start. So the slower spin up of a chuck means that the key will be thrown but probably a lot softer then on a lath with a hard start.
> 
> Sent from my GT-I9505 using Tapatalk


Russian roulette is dangerous, more so with a new semi-auto, than a revolver. Still dangerous. 

Sent from somewhere in east Texas!


----------



## ogberi (Aug 29, 2015)

Chuck key left in the check equals "Hold my beer and watch this!"

Really, it is simple.  Take the dang key out.  Takes two seconds to put it in a safe, dedicated place.  With over a hundred years of apprentices getting a smack in the back of the head for leaving the key in, there is a definite, obvious, safety related reason for it. 

Leaving the key in the chuck is bad, bad, bad to do.   Even if you don't loose a finger, you'll ding the ways, maybe bust the lathe, and definitely make an idiot of yourself.  

Take the two seconds, put the key back where it lives, and rotate by hand.  

<-- Remember, if the guy on a riding mower, chugging whiskey, while shooting a revolver says, "that ain't safe", it most likely isn't safe.


----------



## Line_Bore (Oct 31, 2015)

ogberi said:


> With over a hundred years of apprentices getting a smack in the back of the head for leaving the key in, there is a definite, obvious, safety related reason for it.



Ahhh, memories...
The first time I ran a lathe, I was a freshman in high school.  Old South Bend with the underhead belt drive. I left the key in the chuck to get a drink of water. When I came back, I couldn't find the key. As I was looking in the chip pan, I put my left hand on the spindle housing. Suddenly, things hurt! There was a junior holding my key and watching me cradle 2 new broken fingers and a cracked knuckle. All he said, "Don't ever leave a key in the chuck." After 25 years, I've never forgotten that lesson. 
Can't do that any more, of course. But I digress...

OP, that's a clever setup. Definitely want to do a slow roll by hand before hitting the switch.

Sent from my LG-H345 using Tapatalk


----------

