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johnstda
17th March 2011, 11:42 PM
Does anyone know where I can find a 3-jaw self-centring chuck for a wood-lathe? I have a 1" x 10TPI thread on the spindle, so I figure I can buy a thread adapter if the chuck thread is different, but most 3-jaw chucks are for the metalwork industry. I want to modify dowel rod, so a normal drive centre, well, never ends up in the centre.

RETIRED
18th March 2011, 07:54 AM
You would be better off getting a 4 jaw chuck with the appropriate jaws.

An engineers 3 jaw tends to crush the wood and quite often because of this the wood does not run true.

Have you thought of using cone centres instead of a chuck?

brendan stemp
18th March 2011, 08:56 AM
Have you investigated adapting a engineers 3 jaw chuck? I would've thought you could get an adaptor made for it. The other option for what you are doing is a collet chuck similar to this Vicmarc - Woodturning Lathes, Chucks, Jaws and Accessories - (http://www.vicmarc.com/default.asp?contentID=729)
I use my collet chuck regularly, particularly when I want accuracy.

johnstda
18th March 2011, 10:41 AM
You would be better off getting a 4 jaw chuck with the appropriate jaws.

An engineers 3 jaw tends to crush the wood and quite often because of this the wood does not run true.

Have you thought of using cone centres instead of a chuck?

I can find a 4-jaw scroll chuck but not jaws which grip down to the size of typical dowel; they tend to be more for bowls. The chuck I'm looking at is found at :

Leda Machinery Catalogue (http://ledamachinery.com.au/catalogue/product_info.php?cPath=31&products_id=351&osCsid=4997392b2ff24511fff467604c131691)

but the jaws only grip down to 40mm. I want to be able to hold dowel such as 16, 19, 25mm, etc. dowel. So maybe I just need to find a suitable set of jaws. Are they interchangeable beetween different makes of chuck?

hughie
18th March 2011, 10:50 AM
You would be better off getting a 4 jaw chuck with the appropriate jaws.
An engineers 3 jaw tends to crush the wood and quite often because of this the wood does not run true.



...And I would think that a off the shelf adapter for a 3jaw eng. chuck to fit a wood lathe might be a tall order.

Go with the four jaw wood chuck.

RETIRED
18th March 2011, 12:03 PM
This would do the job.

CWS Store - Vicmarc VM100 Scroll Chuck | Carroll's Woodcraft Supplies (http://www.cws.au.com/shop/item/vicmarc-vm100-scroll-chuck)164486

CWS Store - Vicmarc 35mm Pin Jaws | Carroll's Woodcraft Supplies (http://www.cws.au.com/shop/item/vicmarc-35mm-pin-jaws)164487

RETIRED
18th March 2011, 12:05 PM
Or as Brendan said, collet jaws.

What are you doing with it?

johnstda
18th March 2011, 02:07 PM
Or as Brendan said, collet jaws.

What are you doing with it?

I'm drilling holes through the middle of the dowel rod for use in making bobbins (in spinning, knitting, see Wooden Designs (http://www.woodendesigns.com.au) , then ->Products->Yarn) I've got a Jacobs chuck which opens up to 16mm, but for anything bigger, say 19mm dowel, I have no way of centreing the dowel on the chuck properly.

johnstda
18th March 2011, 02:11 PM
This would do the job.

CWS Store - Vicmarc VM100 Scroll Chuck | Carroll's Woodcraft Supplies (http://www.cws.au.com/shop/item/vicmarc-vm100-scroll-chuck)164486

CWS Store - Vicmarc 35mm Pin Jaws | Carroll's Woodcraft Supplies (http://www.cws.au.com/shop/item/vicmarc-35mm-pin-jaws)164487

That may be what I'm after. What's their clamping capacity? Could they clamp the dowel rods I'm using (16, 19, 25mm etc.)

joe greiner
18th March 2011, 11:31 PM
The 35mm refers to the inside diameter of a hole it fits. It will grip as small as 1/4" (6.35mm) dowel. On larger dowels, it will pinch at 8 locations (the corners of the jaws). Much better than pinching at 3 locations by a metal-working chuck. I use similar jaws on my Grizzly clone of Vicmarc, with a strip of masking tape on each jaw for cushioning 1/2" dowels (12.7mm). Leaves no evidence whatever of clamping.

Cheers,
Joe

johnstda
18th March 2011, 11:38 PM
The 35mm refers to the inside diameter of a hole it fits. It will grip as small as 1/4" (6.35mm) dowel. On larger dowels, it will pinch at 8 locations (the corners of the jaws). Much better than pinching at 3 locations by a metal-working chuck. I use similar jaws on my Grizzly clone of Vicmarc, with a strip of masking tape on each jaw for cushioning 1/2" dowels (12.7mm). Leaves no evidence whatever of clamping.

Cheers,
Joe

Thanks Joe, this clarifies things. I think this is what I need.

issatree
19th March 2011, 01:35 AM
Hi Johnstda,
I use Black Nova Chucks, 3 off, & my Long Pinocchio Jaws have 2 holes for 2 screws, Instead of 1 in that Photo. They are a lot more stable, & the Jaws go down to 1/4in.
If you are struggling with the bigger dowel, whack it up the Morse Taper in the head.
In drilling holes up the dowel, do you use a Rifle Drill, as they are the most accurate.
Are you making Knitting Needles as well.

johnstda
21st March 2011, 04:10 PM
No I use a standard twist drill, coming through from each end. It's not always in the centre and burns the wood a bit, but it should do for the meantime. No just bobbins at the moment (see www.wooden.designs.com.au ->Products->Yarn->Bobbin).

It sounds like the pin jaws are definitely the way to go. Thanks for all your advice.