Chuck thread

[Brian Chandley]

I'm returning to my lathe (see my intro today) and am having misgivings about using my 4" chuck. I want to turn a baseball bat with my son-in-law and tried it using the spur and live center and the blank blew apart. So i decided to use my Delta 4" chuck that I have had for 10+ years and probably haven't used it (or the lathe) for close to that. When I went to use the chuck, I was not able to get it to mount all the way on the 1" 8 tpi spindle - or so I thought. The face plate screws on 100% of the threads. A pic is below.



My question is - is this the proper way for this to sit? It won't turn any further onto the threads. I bought new chuck (Deefiine 4" with a 1" 8 tpi thread) and got the same result. Appreciate any feedback you can offer.

 

[John K Jordan]

It doesn’t look right to me. Be nice for someone to examine it in person.
I’m not familiar with that chuck. I suspect someone here is. Do you have the chuck model number?
Have you used that chuck on that lathe before? If so, do you remember if it fit better then?

I’d do two things: measure and count the threads on both chuck and lathe to make sure they match. (Harder for internal threads but possible.)
Check the threads on both for damage.


I’d also prefer to use a chuck but the centers should work. Maybe describe the steps you used to mount the blank. There are a few ways. Is the drive center a 4-spur type?

Is the blank square or round? What kind of wood?
How did the wood blow apart? Chunk came off, grain at an angle? Split down the length? Fly off the lathe?

What tool - spindle roughing gouge, sharp, large? Did you get s big catch?

JKJ

 

[Rick Moreton]

Does the chuck have a set screw to keep it from coming off the lathe accidentally? If so, it might be poking out and stopping the chuck from seating.

 

[Dean Center]

The Delta chucks were the same as Nova G3 chucks, as far as I recall. They were decent chucks, but may have been made specifically to fit Delta lathes of the era, and it's conceivable they won't screw fully onto a Jet lathe. The base of the chuck really needs to fit solidly flush against the face of the spindle shoulder. Rick's idea is a good one, but I don't see anything sticking out far enough for a set screw to go into.

BTW, you need to step back and consider why the bat blank blew up. Between centers is a very feasible way to make a bat. Putting one end in a chuck will not address whatever the issue was with your first attempt. I strongly urge you to figure it out before you try again. Your safety depends on it.

 

[hockenbery]

want to turn a baseball bat with my son-in-law and tried it using the spur and live center and the blank blew apart

What @Dean Center said. Check the thread depth of both. A thumb on a pencil will be close enough to. Tell you if the spindle threads are bottoming out. If it isn’t bottoming out, check the threads for burs or deformities.

Between centers would be my choice for mounting a bat blank. Unless you had turned it quite thin- “blew apart” would lead me to think you had a defective blank, cracks in a solid wood blank, or poor glue joints in a glue up.
If the tailstock moved or the hand wheel opened up the blank could come free on the tailstock end and beat itself against something possibly splitting the blank. Turning between centers needs a tailstock that locks in place and locking the quill so the handwheel dosen’t open

Consider turning a few mini bats for practice. Use a 2x2x12.
Tool handles
Gavels

I would do some small stuff before turning a Roy Hobbs wonder boy.

 

[Brian Chandley]

Thanks everyone. The practice wood was a 4' long, round bass blank. The real bat will be hard maple. The tool was a roughing gouge. As we got to the handle (the thin end) the pressure caused the piece to break or snap. I feel that the gouge was not sufficiently sharpened. I have since bought a CNB wheel and will try to improve the sharpening. I use a Wen variable speed grinder. I have a 1" skew but I am not 100% comfortable using it. I have since bought some 12" square maple blanks from Bell Forest and will practice on those.

I have backed off the set screws.

I don't understand why the face plate installs fully, but the chuck won't. Both are 1" 8 TPI.

I don't believe these were glued up. They were sold as billets for bats. The billet was warped and was a challenge for the Jet-Mini at medium speed. We use a centering jig to mark up the blank for mounting. I didn't use a punch to assist in setting the spurs.

The spur is a four-spur type.

Thanks for the feedback. I'll return the new chuck and try to figure this out.

 

[John K Jordan]

d

The spur is a four-spur type.

Some people using a drive center with spurs will make shallow saw cuts into the wood for the spurs to fit into. A band saw or hand saw will work. Can drive that way without using as much pressure from the tailstodck.

The practice wood was a 4' long, round bass blank

Is “bass” basswood? That can be really soft and not strong. Might need to back off on the tailstock pressure whether using a drive center or a chuck. (after you get your chuck issue resolved)

How did you mount a 4’ long wood blank on a Jet mini lathe?

Sometimes to see where mating surfaces (like morse tapers and threads) are warped or binding we will color the surface of one and see where the color rubs off. I brush on Dykem Blue for this, but even a magic marker might work. Threads can be distorted and still look ok.

If you know another turner in your area with a 1”x8 lathe (or a Woodcraft or other store) maybe you could take your chuck and faceplate and try them on the other lathe and vice versa, ask them to come to your place and bring a chuck.

Tools MUST be sharp. If learning to sharpen, an experience person could be a great help. Are you a member of a woodturning club? There are always people at clubs ready to assist.

JKJ

 

[hockenbery]

I'll return the new chuck and try to figure this out.

How did the depth of threads on the new chuck compare to the length to the threads on the spindle?

On thing that I do occasionally is run the lathe backwards ( by hand or at show speed) with a pencil lead in the threads. A couple of passes cleans out dirt in the thread grooves and may add a bit of lubrication.

 

[Jim Holcombe]

Brian, is there an internal shoulder on the chuck that stops it from threading further onto the spindle? Do some measuring on both the chuck and faceplate to see if there’s a difference in how far they can thread on.

 

[Jon Rista]

I feel like a piece of the chuck is missing... Is this a chuck that supports interchangable inserts? If so, it is possible you are missing the insert? Also, is there any chance that there is a missing collet for the lathe? Something that would take up that space there between the shoulder of the spindle and the chuck? In any case it does look odd. "Wrong" as John said. I have a Record Power chuck that supports many different inserts for different size spindles/threads. Its easy enough to leave that off and forget it, if its been removed...