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smidsy
18th Nov 2004, 09:35 PM
Hei Guys,
I've just got these and I have never seen them used so I need to double check.
I am assuming that the steel tube spacers go inside the nylon stoppers and that the washers go at the head end of the allen head bolts - correct?

Also, I am thinking of putting adhesive felt on the stoppers to protect the work a little more - has anyone done this?
Cheers
Paul

Baz
18th Nov 2004, 09:39 PM
Paul, yes to your first question and no to the second. I have used the bowl jaws a fair bit and have not noticed any marks left by the rubber/nylon/plastic jaws.
Cheers
Barry

Cliff Rogers
18th Nov 2004, 10:44 PM
G'day.

What Baz says....

I'd steer clear of the sticky stuff, I find that the gummy glue from those peel &
stick things goes spewy with heat & leaks out to make a make a mess. :eek:

If you are doing something realy soft, here's a trick I use when I reverse a
small bowll into a large set of metal jaws, get a roll of paper towel, tear off
a couple of sheets & lay it over the top of the bowl.
Now carefully mount the bowl, towel & all into the jaws.
My 130mm Bonham winds out to take a bowl that's almost 7" across.
If you are careful, you won't get marks. :cool:

smidsy
19th Nov 2004, 02:31 AM
Hei Cliff,
These jaws are spec'd at 285mm with the chuck closed so it would take about a 320mm bowl with the jaws open.

On first impression they look a great piece of gear and reasonably priced at under $100. A t-bar allen key to match the ones that came with the chuck would have been nice but I spose I'm just being a fussy git.

These jaws have an added feature for those of you who need to smuggle new toys past the wife in that the box they come in looks a heck of a lot like a pizza box. :D

Thanks for the info guys.
Cheers
Paul

rsser
19th Nov 2004, 07:50 AM
Another option for finishing the base/foot of a bowl is to use a vacuum chuck. Vicmarc make one, or you can do your own using plans off the web and an old domestic vac.

I use both systems. The vac chuck is quicker to set up but it can be a bit fiddly to centre your bowl. On the other hand, you can make up a spacer out of pvc pipe in order to mount natural edge bowls.

Cheapest option is the tailstock used in conjunction with a jam chuck or rubber-covered 'driver', leaving a stub to saw off and clean up by hand.

gatiep
19th Nov 2004, 01:31 PM
Ern

If you use the following method when turning the bowl it's a piece of cake to center the bowl.

While you have the blank on the screw or whatever and finished turning the recess for the chuck, just bring the live center and tailstock up to the recess. Make a very small dimple in the wood with the center point. Turn as usual. When you want to set it up on the vacuum chuck put the live center in the dimple and screw up the tailstock. Now apply the vacuum, then remove the tailstock. There is always a difficult and an easy way to anything ................this is the easy way for me.

Enjoy the weekend

:)

rsser
19th Nov 2004, 05:11 PM
A beautifully simple solution - thanks Joe.

Would work with spigots even better, which is my preferred chucking option these days.

Baz
19th Nov 2004, 08:47 PM
Paul, to make it easier to change the stoppers I cut the leg off an allen key (the right size) and use it in a cordless drill, using a low setting on the clutch.
Cheers
Barry

smidsy
19th Nov 2004, 11:15 PM
Hei Barry,
That's what I usually do with cheap allen keys as I have good sets that I bought when in R/C - although when I was in R/C I actually bought a full set of t-bar allen keys as well and I only ever used the smaller sizes so I shall have to have a scrounge around and see what I can find.

When I was assembling my MC900 I cut an Allen key to put in a socket ratchet which made life a hell of a lot easier.
I don't think I've ever seen allen key drivers for the cordless drill which is suprising.

Thanks for the info guys, I'm planning on having a play tommorrow so hopefully I have a pic or two.

Cheers
Paul

rsser
20th Nov 2004, 06:45 AM
Clutch is essential when using a hex driver in a cordless drill, otherwise you chew up the driver or worse.

smidsy
20th Nov 2004, 02:44 PM
Hei Ern,
I would be loath to use a cordless driver at all on this since murphies law dictates that sooner or later I would forget to set the clutch to the lower setting (I generally don't use the clutch anyway) and with the plates being cast aluminium it would be all too easy to strip the threads - with the standard allen key it was easy anyway and with a T-bar allen key it will be a breaze.

I just had my first use of the jaws and they were very easy to use and set up and seem extremely well balanced as there wasn't any excess vibration.

One thing I noticed is that you have to tighten the chuck on the shaft (I usually just screw the chuck all the way on, it tightens as you work anyway so I've never seen the need for specifically tightening it) as the weight of the bowl jaws create enough momentum to spin the chuck off the shaft. On the MC900 you slow to minimum speed before you turn off the lathe, but on lathes where you change the speed via the belt and start/stop at high speed this could get interesting in a hurry.

I'll post a few pics this arvo.
Cheers
Paul

rsser
20th Nov 2004, 02:57 PM
Yes, better safe than sorry.

Now a simple locking cam and shaft on each button would speed things up; wonder what it would do to the price.

There's certainly a lot of flying metal and wood when you get one of these holding a big bowl and running at max. Like a windmill; think I might tape a few cardboard vanes on the outside edge come summer ;)

smidsy
20th Nov 2004, 03:11 PM
Hei Ern,
I don't think a locking cam is the answer since you would need the lathe shaft to match. You could prossibly put a lug in the chuck adapter to lock the chuck against the shaft but this could lead to thread damage.

Whether you're turning a pen or a 300mm bowl what we do is inherantlly dangerous because of the speeds we work at and the fact that wood is an imperfect medium. I think it is just a case of situational awareness and being aware of what problems may occur so those problems can be minimised.

Now that I know that run off is a possible problem all I need to do is hold a polishing rag or similiar against the work when I turn the lathe off.

Cheers
Paul

rsser
20th Nov 2004, 03:32 PM
Paul, I meant a shaft and locking cam on each of the red buttons on the Cole jaws, to replace the allen head screws.

smidsy
20th Nov 2004, 04:34 PM
Ok Ern I get you.
To be honest I this would be fiddly, and it would also add to the cost.
I think the allen key bolts work fine, and at less than $100 it really is a cost effective bit of kit.
Check out my new post, I've thrown up some pics.
Cheers
Paul