Jacob's chuck movement

Re: Jacob's chuck movement

Gary Evans, Tallassee, TN

>Ruth,

The good ones have a threaded hole in the end of the morse taper so that you can run a threaded rod in from the back side of the spindle to hold it in place.

Gary

Re: Jacob's chuck movement

Pete in Holland, MI

>A Morse taper was not designed to be used with pressure that would tend to separate the tapers. Was designed for tools that would have pressure forcing the tapers together (drills, spur centers, etc).

Make sure that the stub and your lathe's spindle are clean and burr free. The only true way to keep it in place would be to drill and tap a hole in the tang, then thread a draw bolt thru the spindle and tighten it on the other end of the spindle. Haven't quite figured out why chucks are sold with that taper on them and not be provided with a draw bolt.

Also, making sure all your turing strokes head towards the head stock, and not away from the head stock, would help.

Good luck.

Re: Jacob's chuck movement *LINK*

Fred in NC

>Ruth, this assumes you are using a Jacobs chuck with a Morse taper.

Morse tapers don't like lubrication and dust. I wipe once in a while inside the spindle with a dry lintless cloth. Don't use any kinds of abrasives !!! Also wipe the Morse taper. I have not had much problem with the tapers coming off.

However, the real solution if you are going to use the Jacobs chuck for a while is to use a DRAW BAR. This means using a Morse taper that has internal threads in the narrow end. They are usually 3/8" - 16 TPI. You get a piece of threaded rod in the taper, and a washer and wing nut (I like Nylon ones) to hold it through the spindle. Don't overtighten!! To get the taper out take off the nut, and hit the end of the rod with a mallet.

Most Jacobs chucks have replaceable tapers, in other words, the Morse taper comes off. However, some have internal threads and some use a taper, which can be more than one kind.

See the link for a Morse taper for drawbar.


Morse taper with internal threads

Just in case

Fred in NC

>You want to get one, I would call the number in the main page. A matched taper and chuck is about $18 plus shipping. You have to get your own threaded rod, washer and nut locally.

Thanks

Ruth in So. Cal

>I do try and always turn towards the chuck but can't do that all the time. I know my cheepo Sears screw chuck mandrel has a threaded hole in the end, and only last night was wondering what it was for!!! I am not sure if the Jacob's does and will look tonight. I have had it so long I can't remember if it is one piece, should I assume it is two pieces, bang out the mandrel from the chuck side and get one of the adaptors in Fred's post?

Ruth . . .

Fred in NC

>That would be best. However, like I mentioned before, there are 3 kinds of Jacobs chucks (that means commonly in use). One connects to a thread on the end of the Morse taper, and then there are 2 that have an internal taper. They are not interchangeable. I would talk to Chris at LittleMachineShop, he will help you. They are very nice people, and I am a very satisfied customer. Prices are very good, and shipping reasonable.

Re: Ruth . . .

JamieDonaldson

>Just give it a whack on the nose with a 16 oz. alignment tool, but first place a block of wood over the jaws to protect them!!

Re: Ruth . . .

John Lucas

>Jamie

It still comes loose eventually. I use a deadblow hammer and I'll get about a dozen or so and then it will come loose.

Now I use a steel pin chuck that i put in the small jaws of my chuck. This reduces the vibration that I used to get when I put a wooden down in the stopper and turned it with this in place. I just insert the dowels in the wine stopper when I'm finished turning.