4 jaw Self centering chuck recommendations please

Hi, I'm in the market for a 4 jaw self centering chuck for my Boxford C lathe. I'm considering the following

ARC Euro Chinese origin 125mm - £97 Link

Sanou (Ebay) Link

Are there any other better alternatives in this price range?  My preference at the minute is the ARC one due to reliable customer support should I have any isses.

Both will need a back plate - ARC Euro - £22 Link

Thanks

Aled

Edited By Aled Dafis on 02/09/2019 23:33:02

Hi Aled

I do have a couple of Sanou 6 jaw chucks but have not yet put them into service so cannot comment on their accuracy. They do however appear to be fairly well finished and the jaws to meet correctly. Incidentally the largest is a 250 mm chuck so they do get up to the "industrial" sizes.

Before buying I did find a video on the internet ( sorry I don't have a link ) that covers the dismantling and cleaning of one of these chucks ( a self-centering four jaw if I remember correctly ) which the author recommended doing before using.

This would also include removal of any small burrs.

Overall the reviews would indicate that they are fit for general purpose work.

Cheers

Pero

I have an Emco 4 jaw self centering chuck that is a really good and has great repeatability as well. No idea if they are still made or their price now days.

Neil

Emco are over budget at £330

Aled,

My comment would be: why self centring?

Self-centring chucks are not generally the most accurate as far as centring is concerned.

Only one pair of jaws will grip tightly on anything that is not precisely circular or square. That cannot be accepted as good, either for work-holding or for loadings on the chuck scroll (being concentrated on only two points on the spiral) for anything even only a little out of perfect shape.

I have a couple - one good quality 160mm chuck arrived with my lathe and does get used, but no more than a 100mm 3-jaw (much lighter!) or 4-jaw independent. I bought the other (a 125mm HBM - so not exactly of poor quality!) for a rotary table but am replacing it with a higher quality 3 (or a 4 jaw independent) so it can be used on ‘odd’ shaped items. The 4 jaw independent alternative is the current favoured choice.

Further, a 4 jaw independent can be used on rectangular workpieces and for off-setting from the lathe centre line, so far more useful IMO.

Lastly, you don't have to worry about losing the ‘other set’ of jaws with an independent 4 jaw.

Aled,

I have two TOS 4 jaw self cantering chucks; one on a small lathe and the other on a Myford S7. Both are of excellent quality and dead accurate.

Eric

Again the Tos are well out of the OP's price range at about £300 for a 125mm

"Are there any other better alternatives in this price range" which is £50-100

It might be worth considering the extra few quid for a sanou 6-jaw chuck for flexibility and still circa £100

I have an Arc one on my SC4, it doesn't see the same amount of use as the 3-jaw but I'm very happy with it. Not essential but when you have a job that suits it, it's really convenient.

Some people prefer them to a 3-jaw for general work.

Neil

Not a 4 jaw, but I am not happy with my Sanou 3 jaw - the jaws are very loose in the body. in axis of the chuck.

Dial set to zero, with the jaw press up against the scroll in the direction of the dial ( finger pressing is out of image on the right)

Then lifting the front of the jaw up, away from the body, while keeping the jaw pressed against the scroll in the dial direction...

There is a similar amount of movement from side to side...

Holding any part that is shorter than the length of the jaws is a mess - the jaws simply bell-mouth, and not to the same amount...

I honestly believe that skimping on the chuck is a big waste of money. You pay big bucks for your lathe, and assuming its good, with good bearings, a good spindle and register, then spoil it with a mediocre chuck...which you have to argue with every time you use the lathe. Maybe a good chuck has a price to balk at, but treated well it will last your lifetime.

This Sanou is now used in a jig I made for stamping numbers of handwheel peripheries - it's only good when hammered..

Edited By Joseph Noci 1 on 03/09/2019 10:53:49

Has anyone seen a vendor offering these with a set of outside jaws included (or even available?)

Thanks

Bill

If you don't mind only two of the jaws being really tight at a time, then go for it. The only self centring chuck which is guaranteed to grip on all its jaws at once is a three jaw. So many people are scared to use a four jaw independent, which needs truing up each time, but is the only way to go if positive clamping and true running are of any interest at all. Soft jaws are great for special jobs, but take up much more time to set up.

A quick search shows Bison chucks can have both sets - if you have the spare grand one of those costs..

link

pgk

They only show stepped or tapered on their website.

I use a 125mm four jaw from ARC, it was one of the narrow ones a little lighter than the full chuck. It works great on my SC3 when I need to hold bigger diameters than the standard 80mm three jaw.

Have another look at ARC, I've just had a notification that they've slashed the price of some of their 4Jaw SC chucks - almost in half

Rod

The only off-brand one I have seen with both sets of jaws is by a seller called niuniucme on eBay. Unfortunately, they are in US but if you have a contact there, it may be of some use.

For brand name ones in UK, Rotagrip are competitive.

Thanks Jason, yes I've seen that, but several ebay vendors, both UK and Chinese, show a table/spreadsheet which shows the dimensions for the external jaws, but no-one I've spotted actually seems to be able to supply them. I've seen photos of them, but only for the K13-250, which is a bit on the big side.

Maybe Sanou used to make them, and once displayed this table of sizes on their website, but now discontinued.

Bill

Thanks for all your replies, you've both answered some of my concerns/thoughts and asked more questions.

My intention from the outset was to purchase both a 4 jaw self centering chuck and a 4 jaw independent at some point. The self centring is just so convenient when turning square bar, I've always had access to one at both my school workshops.

I think that I've now sourced a 4 jaw self centring chuck, so onwards to looking for an independent one. Any reccomendations...?

For a four jaw independent, you might look at Arceurotrade, click on their advert at the top. They sell Chinese and Indian chucks. You would also find that getting a lever type of indicator would be easier than the plunger dti for use with this type of chuck.