DIY Custom Lathe Chuck adapter?

[Massis]

So I finally got round to ordering my new lathe. Now I'm looking for the easiest way to chuck my briar with the materials I already own.

At the moment I use a OneWay Chuck with #2 tower jaws. In the future I might have custom jaws made, but for now it's sufficient.
This mounts to my old lathe with an adaptor like this:


This threads on the - obviously threaded - spindle of my super7.
However, the new lathe has a taper spindle, not a threaded one if I'm correct, and I plan on keeping the factory provided 3-jaw chuck mounted to it.

Seeing as Ken Lamb makes a briar chuck made of aluminium which mounts to your 3-jaw with a tenon, I am thinking of making my own adaptor like the above one out of aluminium.
So instead of making a hollow adaptor with threads, I would make it solid with a tenon protruding from the back, so I can mount the OneWay chuck in the 3jaw.

The question is: Would that be safe? Will aluminium do the job, or would it require steel?

[RDPowell]

Personally, I would not want a aluminum spindle adapter on my lathe with the stress that's exerted at that point,
I think steel is the way to go here but, that's just my personal opinion.

[W.Pastuch]

Steel.

Regardless of the material choice, I understand you were planning to make the adapter yourself? That might be a bit of a problem, unless you have access to a very serious lathe. You say the spindle in your new lathe has a Morse taper- machining a morse taper is not easy and it's not something I would try to do myself (unless we're talking about an ebonite army mount). It takes a lot of precision to machine a morse taper and any error might result in the taper unlocking and flying loose off of your lathe. Make sure your setup is safe, saving a couple hundred bucks isn't worth risking your safety.

[Massis]

It is not a morse taper, the hole in the chuck is tapered and the adaptor has screws going through which pull the chuck onto the taper and lock it. So coming loose is less of a risk.
This would lead lead me to assume precision would be slightly less crucial then a friction locked morse taper?
I am not going to mount this chuck on the spindle of my new lathe, but in the 3-jaw chuck of my new lathe, like Nate King does/did for example (saw it on the forum here)
the lathe I would be making this on would be the new 10x22" Tu2506 from optimum. Maybe I'm better off having it made as this will take a beating when turning unbalanced briar...

An alternative would be to buy a new adaptor for M30 thread for €25, and just thread a steel rod for a tenon. Downside is that it'll only spin one way because of the thread, but it'll be safe in the other direction and alot easier to make.

[caskwith]

Nice big chunk of steel, turn it perfectly round then chuck up on the 3 jaw, make indexing marks on the adaptor and the chuck then turn and thread the other end to fit the chuck for the briar. Pretty straightforward assuming your new lathe can cut a 12 tpi thread. Remember the thread form is whitworth so your threading tool needs to be ground to 55deg.

[Tyler]

I'd just grab the outside of that adapter in my three-jaw. Done.

[Massis]

really!? That would give you less than 1/2" to grip onto with at least 6" sticking out. Sounds like a really bad idea imo...

@Chris: should be doable, new lathe comes with a double set of change gears, that will in fact be the cheapest

[W.Pastuch]

Sorry, it looks like I misunderstood your explanation.
Good luck with the job, threading on the lathe is a skill I lack for now- haven't had a good reason to learn yet.

[caskwith]

Best of luck with the project, make sure you get extra material to take off the pressure of getting it right first, time.

[Tyler]

really!? That would give you less than 1/2" to grip onto with at least 6" sticking out. Sounds like a really bad idea imo...

@Chris: should be doable, new lathe comes with a double set of change gears, that will in fact be the cheapest

I take it the long thread part goes through the chuck then, and doesn't stick out the back?

[Massis]

normally the long smooth part goes into the chuck, and threads over the spindle, while the widest but short part sticks out the back. So not much to grab on to.

[Tyler]

normally the long smooth part goes into the chuck, and threads over the spindle, while the widest but short part sticks out the back. So not much to grab on to.

I actually have the same chuck, but mine came with the the adapter installed. I didn't realize it looked like that, so I thought your was different.

I grab mine on the 1/2". My three-jaw is good, and it's solid as a rock on the 1/2". I don't love the arrangement, and would like a dedicated chuck, but until then I works for the pipes I occassionally turn.

[Massis]

Thanks for the info! At least now I know I won't be stuck without a briargrabbing chuck until I can get a decent one

New lathe should arrive today or at least this week :exited:!

[2combs]

Another option would be to buy a lathe spindle adapter for going from another spindle size to what your wood chuck is. They're cheap and it'll give you more area to grab if you're concerned with that. That's what I did here. I cut the part with the flats off so my small 3 jaw chuck would grab it well. This adapter was $15 shipped to my door.

[caskwith]

If you are going to use a method like this I would really recommend adding a draw bar through the headstock for added security.

Another option would be to buy a lathe spindle adapter for going from another spindle size to what your wood chuck is. They're cheap and it'll give you more area to grab if you're concerned with that. That's what I did here. I cut the part with the flats off so my small 3 jaw chuck would grab it well. This adapter was $15 shipped to my door.

[2combs]

If you are going to use a method like this I would really recommend adding a draw bar through the headstock for added security.

What would be the need for a drawbar? I'm not dealing with a taper of any kind.

[caskwith]

If you are going to use a method like this I would really recommend adding a draw bar through the headstock for added security.

What would be the need for a drawbar? I'm not dealing with a taper of any kind.

3 jaw chucks don't hold perfectly concentric and over the years get a bell mount from the scroll closing method. This decreases the already small gripping area. You are spinning a large, heavy, unbalance load and carrying out interrupted cuts and heavy drilling operations. For me the chances of it coming loose, especially if drilling and turning a large batch of pipes at the same time, would worry me so the simple addition of a drawbar would keep it firmly pulled back into the 3 jaw and make coming loose almost an impossibility.

[2combs]

3 jaw chucks don't hold perfectly concentric and over the years get a bell mount from the scroll closing method. This decreases the already small gripping area. You are spinning a large, heavy, unbalance load and carrying out interrupted cuts and heavy drilling operations. For me the chances of it coming loose, especially if drilling and turning a large batch of pipes at the same time, would worry me so the simple addition of a drawbar would keep it firmly pulled back into the 3 jaw and make coming loose almost an impossibility.

Yeah, I can see that. I prefer to drill and turn my stummels on the wood lathe, so I just did it to be able to move the chuck from the wood lathe to the metal lathe while the stummel is still in it for certain cuts that I might want to make. Shank caps, inlays, calabash work, etc. So I had light, slow, precise cuts in mind. Thanks for the heads up.

[caskwith]

3 jaw chucks don't hold perfectly concentric and over the years get a bell mount from the scroll closing method. This decreases the already small gripping area. You are spinning a large, heavy, unbalance load and carrying out interrupted cuts and heavy drilling operations. For me the chances of it coming loose, especially if drilling and turning a large batch of pipes at the same time, would worry me so the simple addition of a drawbar would keep it firmly pulled back into the 3 jaw and make coming loose almost an impossibility.

Yeah, I can see that. I prefer to drill and turn my stummels on the wood lathe, so I just did it to be able to move the chuck from the wood lathe to the metal lathe while the stummel is still in it for certain cuts that I might want to make. Shank caps, inlays, calabash work, etc. So I had light, slow, precise cuts in mind. Thanks for the heads up.

That'll be fine, whenever possible try and use a tailstock centre, not only is it safer in terms of holding the work but you can also take a heavier cut and are less likely to snap a shank or something.

[Sasquatch]

I chuck my oneway into the 3-jaw just as Tyler is suggesting.

One thing of import is that on all these chucks you must tighten each jaw or at least tighten at every port before the chuck is locked. Many people wonder why they have disasters and unless you have a certain type of chuck, you need to put the chuck key in every position to tighten it.

Anyway I'm still alive so Tyler's not totally full of shit on this issue.