Getting the chuck off a Vevor dividing head

[timdotdParticipant @timdotd]

I’ve just picked up a second-hand, unused Vevor dividing head (this is it listed on my local site, but afaik these things are available from all over the place from Amazon and so on)

This is the dumbest of dumb question, but: how on earth can I remove the chuck? As far as I can tell it’s screwed into the spindle nose, but if that’s the case it must have been torqued on by an elephant jumping up and down on a 10m bar. Is there a way of getting this off that isn’t going to destroy the entire thing in the process…?

[bernard towersParticipant @bernardtowers37738]

It might help if you pour boiling water over the chuck first then with a bar ACROSS the jaws give it a smart tap, best of luck!

[John HinkleyParticipant @johnhinkley26699]

From the pictures in the advertisement to which you linked, I would say that it is simply a matter of loosening the screws that secure the chuck to the backplate and freeing it from the register.  It might need al little gentle persuasion with a dead-blow hammer to free it off if it’s been standing for a while.  I would be surprised if it was screwed onto the spindle.  I have had a number of rotary tables/dividing heads over the years and I can’t recall any of them having a threaded spindle. (Myford owners will now round on me for suggesting that.)

John

 

[Tony Pratt 1Participant @tonypratt1]

Sorry John H my dividing head and indeed the one shown in the link have a threaded back plate [mine has a Myford 7 thread] so it’s just a matter of unscrewing said chuck/backplate assembly. Not an ideal method of attachment for milling! The black grooved collar shown below covers the thread.

Tony

[Tony Pratt 1]

On Tony Pratt 1 Said:

Sorry John H my dividing head and indeed the one shown in the link have a threaded back plate….

As does my 5″ Elliott universal dividing head. The nose thread is 2″-10 UNS.

Julie

[Michael GilliganParticipant @michaelgilligan61133]

These should help:

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MichaelG.

[John HinkleyParticipant @johnhinkley26699]

That’ll teach me to buy cheap, then. Should’ve kept quiet.  As it’s said, “better to stay silent and look a fool, than speak up and confirm it!”

In my defence, the OP did ask how to get the chuck off, not the backplate!

John

 

[Peter Cook 6Participant @petercook6]

This guy seems to have had the same problem with a similar head.

[timdotd]

On 5 April 2026 at 09:51 timdotd Said:

Is there a way of getting this off that isn’t going to destroy the entire thing in the process…?

What will destroy the head is if you use the worm and wheel or the spindle lock to resist the torque from your 10m bar.

Hence, apply as much torque as you like, just find a way to apply a corresponding amount of counter-torque in a non-damaging manner.

An expanding plug in the back of the spindle might be a good place to start. Heave on it with the worm and spindle lock disengaged and the worst that will happen is the plug will slip in the bore.

[BazyleParticipant @bazyle]

I is probably held by a combination of old oil having gummed up and possibly the common lathe problem of a hot chuck put onto a cold mandrel and forming a bit of a shrink fit.
Unbolt the chuck so you don’t have that mass to bother with, revealing the backplate and the end of the spindle. Decide on and make ready your method of applying the releasing forces.
Make a wooden or thick very thick cardboard disc to place over the spindle end and fill the hole with a big bolt or MT2 taper (but don’t get that stuck too) to add thermal mass. Now you can quickly heat the front of the backplate with a paint stripper blower hoping not to heat the spindle (and its bearings and their grease). When just too hot to touch (40C) unscrew it. A sharp tap method is the best if possible.
If it doesn’t cooperate the first time cool it in the freezer for a day and try again.

[DC31k]

On DC31k Said:

What will destroy the head is if you use the worm and wheel or the spindle lock to resist the torque…

I disengage the worm and use the direct indexing plate and plunger to resist any applied torque.

Julie

[timdotdParticipant @timdotd]

Thanks, all – there’s a short sequence in one of the linked videos where the chuck is “persuaded” to unscrew that was the source of inspiration.

The solution turned out to be warming the spindle nose area up with a propane torch to just-too-hot-to-touch, then cranking down as hard as possible on a right-angled piece of rebar in the jaws and walloping it until it finally gave way.

It probably took less violence than it felt like, but was worth doing – the interior gearing appeared to be greased with grinding paste rather than anything approximating lubrication, and the mating surfaces looked like raw sand castings. It took an entire afternoon to clean up, but it’s a completely different device now…

[Michael GilliganParticipant @michaelgilligan61133]

Well done, Sir

MichaelG.

[old martParticipant @oldmart]

The Vevor 160mm six jawed scroll chuck that I bought had had the inside jaws ground after assembly without being cleaned afterwards.The chuck was dismantled and washed before use and has prooved to be outstandingly good at all diameters whichever the jaw tops are facing, I was very lucky as the name has very mixed reviews.

[timdotd]

On timdotd Said:

the interior gearing appeared to be greased with grinding paste rather than anything approximating lubrication, and the mating surfaces looked like raw sand castings. It took an entire afternoon to clean up, but it’s a completely different device now…

And there are some that think the light shines from vevor products.🙂  Tim is just another customer who has likely avoided a short-lived purchase.  Well done, Tim.  Now to check if the head mis giving good accurate readings during operation….

[timdotdParticipant @timdotd]

I’ve no complaints about Vevor quality now I’ve cleaned it up.

For the price point I don’t have a problem with stripping it down and giving it a clean before use. We can’t have it both ways; EITHER we have access to tools at a price point which allows us “normals” to use them AND have to put a bit of time into setup and maintenance; OR we have to accept that we’ve not going to be able to afford the tools in the first place (or we’re restricted to cast-off industrial tools that have been beaten to bits during their lifetime and are probably in worse state than the China imports).

Sometimes I wonder if there’s isn’t an element of gatekeeping going when the moans about import tooling quality get TOO strident – squint a bit, and sometimes it starts sounds a bit like “these wobbly cheap tools that anyone can buy off eBay and start making chips the next day, now when **I** was a lad, you couldn’t buy off eBay, I had to file my own mill out of a square block of tool steel etc etc etc”…”

[not done it yetParticipant @notdoneityet]

I don’t wonder, but I know that a lot out there buy things, like your purchase, and haven’t a clue as to why it will wear out quickly until it is too late.  They just trust the cheap items as good value for money.  I always say ‘buy cheap, buy twice’.

You have clearly avoided that trap – this time.  Bought cheaply (before it was worn out) and repaired it at some cost (especially if you would need a professional to fix it for you).

[PeteParticipant @pete41194]

I don’t believe in subjecting any chuck to hard shock loads and heavy stress directions there not designed to take. Chuck bodies and the jaw slots are easier to spring into permanent deformation by heavy side loading the jaws or even over tightening than some think. Better I think would be to remove the chuck from the back plate, use a couple of well fitting bolts and nuts through the back plate bolt holes, and use those with a bar to remove the back plate off the dividing head spindle.

However you did get it off. There’s an old machinist trick for mostly preventing the same from happening again on any threaded spindle including lathes. Unless there’s contamination or corrosion also involved, threaded chucks get hard to remove because of how the spindle and back plates are designed to work. As the chuck gets tightened on the thread, there’s a slight amount of elastic thread stretching involved and no different than any threaded connection. But the majority of the issue is caused by the metal to metal frictional contact between the spindle chuck register face and the internal face in the back plate recess. With very well finished surfaces and heavy tightening, I’m not so sure there isn’t a bit of Van Der Waals forces being at least part of the cause for seized or very hard to remove chucks as well. Cold welding between close fitting parts is a real effect, and even more so for anything tightened and joined face to face over long periods of time.

Cut a thin (.010″-.020″) cardboard washer shape slightly larger for the hole diameter than the plain un-threaded portion of the spindle nose behind the thread. And its outside diameter slightly smaller than the back plates recess. Single thickness paper and cardboard is extremely consistent for thickness and parallelism because of how its manufactured. Soak that cardboard washer in some light oil for a minute or two, blot off any excess and use it between the back plates face and the spindle registers face. It will compress slightly as the back plate face tightens up against the spindle face.

The oil helps a bit with chuck removal, but also prevents the cardboard from absorbing any humidity and possibly causing rust. There’s also just enough give in the cardboard to prevent a seized chuck, and it will be much easier to remove the next time. Those cardboard washers are also not that durable, so make a few spares. It was the very first thing I did after getting the chuck off my own dividing head. Frankly I think threaded spindles and especially on any milling accessory should have been changed to something better, and at least 80 years ago.

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