Chuck Key

S

scottjhicks

Registered
Registered
Joined
Feb 23, 2014
Messages
7
Hello group! I am noob at machining and I want to make another chuck key for my 4-jaw chuck. I know I have one to base it off of, but I have a few questions. If I were deciding what kind of stock to start with, square or round, which would be the best option? I have both a mini mill and lathe.

There is three basic parts of the main shaft. The square that fits the chuck, the remainder of the shaft that is round, and the hole in the other end that holds the other round rod. Is it best to start by turning the entire length? If you chose round stock then I would say this is the way to start. If you started with square stock, then I would think it would be easier to drill the hole in the end first, being it's easier to drill from a flat surface. Then mill down the square end since would be easier to indicate from a square stock. But all of those are based on starting with a square stock. I think if you started with round stock, then it wouldn't matter as much, so i would start with turning the entire length to size followed my either end.

Any advice or suggestions?

Scott
 
In the lathe:

Start with round stock.

Turn the body to size first

Turn the square end to the OD of the square, as measured diagonally across the points of the square.

Cut off, and face the cut end to length. Drill and tap for a set screw to hold the T-handle in place.

In the mill:

Put the piece in the mill vice

Locate the edge and move over to the center, the fixed vice jaw makes a good place to measure from

Center drill and drill the hole for the T-handle.

Mill the first flat for the square in the same set up

Rotate 180 degrees, and align on the T-handle hole using the same drill bit that you used to drill with. You already know where that hole is. Leave the vice a bit loose, and insert the drill through the hole. (the drill is already in the chuck). Tighten the vice.

Mill the second flat. Now you have 2 opposing flats.

Now rotate the piece 90 degrees in the vice, holding it only by the flats. Support the free end of the piece with a jack screw or by shimming. I use my hold down bolts and nuts for this many times. Make sure it is up high enough to that your cut will clear the vice jaws.

Once that cut is made, then rotate 180 degrees again and make the final cut.

Deburr and use.
 
Jim, thanks for the replay. I think what I have lying around is mostly round stock anyways and that was what I was planning on using, but wanted to see what others thought. Thanks for the thoughts and I'll give it go as soon as the bearings for my lathe show up so I can put it back together.

Scott
 
I made the cross-rod a press fit and bent one end 90 degrees, so I have a nice crank handle - good for making bigger adjustments without wearing out your wrist.
 
burgermeister,

That's a pretty neat idea. Do you have a picture I could see? I get the idea, I'm just curious what your's looks like.

thanks,

Scott
 
Chuck,

Thanks! I have found a few of the sites you sent me suit me fairly well.

Scott
 
On this subject, has anyone made a spring loaded chuck key? I didn't get a chuck key with my used lathe, so I use an old tap wrench with a square key in it. I would like to make a spring loaded as they are pretty pricey to buy.
 
hardware1170 said:
On this subject, has anyone made a spring loaded chuck key? I didn't get a chuck key with my used lathe, so I use an old tap wrench with a square key in it. I would like to make a spring loaded as they are pretty pricey to buy.
Click to expand...

I normally remove the spring from my chuck keys, IMHO they are a pain to use. On the other hand, if my hand is not on the chuck key, then it is not in the chuck.
 
Chuck key with bent handle - no mill at the time, so I just made the square end on a bench grinder. It's A2, and my first attempt at heat treating, so it isn't very hard - but it is functional.

IMG_1710.jpg
 
You must log in or register to reply here.
Back
Top