home made cole or button jaws

[treefella83]

i have been thinking about making a set of these for some time now and here is the result.

i am happy with the end result but the jaws were made from 18mm ply wood which is poor quality so i might try again with mdf.
next project is a new grinding jig some how adjustable to sharpen different tools

 

[Blister]

who's a clever boy the , looks good to me :lol:

Nice design

 

[PowerTool]

Nice job - any work-in-progress shots ? I've been thinking about making a set,so any advice/ideas welcome

Andrew

 

[Bodrighy]

O.K. At the risk of appearing completely stupid, how do they work?

Do you have to make the bowl or whatever to fit the jaws? they seem to be adjusted in specific sizes.

 

[paulm]

Pete,

You adjust the fit of the jaws using two variables, one is the position of the buttons on the jaw plates, the second is that the jaw plates themselves have a range of movement in and out using the range of adjustment on the scroll chuck itself, usually around 20mm or so I would guess.

Using the two variables in combination you should be able to fit any size bowl up to the max settings.

Very useful, but not essential, you can do a lot by reversing a bowl onto a foam friction drive supported lightly by the tailstock and finish off by hand the last bit of the base off the lathe, probably quicker than fiddling around swapping jaws over etc unless you keep them mounted permanently on a spare chuck.

Cheers, Paul.

 

[Russell]

I have exstended the vicmarc/rp4000 cole jaws by using MDF plates they now have a diameter or 65cm

 

[SVB]

Try a search on the Longworth Chuck. A similar item but another option.

 

[bwlossie]

Chisel,
Can you please explain for a novice "foam friction drive".
Photos would be helpful.

Barry.

 

[Bodrighy]

Chisel,
Can you please explain for a novice "foam friction drive".
Photos would be helpful.

Barry.

Oh good, glad someone else has to ask the silly questions :lol: [/b]

 

[paulm]

For the friction drive, turn a piece of timber to fit your chuck jaws and protrude say 6" in front of the jaws. Can leave the end furtherst from the chuck a wider diameter than the chuck end if you like. Pad the far end with some washingup sponge or similar, I also stuck on some router mat to give extra grip.

That's all their is to this hi-tech device ! To use, once you have turned your bowl as normal and are ready to finish off the bottom, just grip the friction drive in the chuck jaws, hold the inside of the bowl against the friction drive and gently bring up the tailstock to gently but firmly apply some pressure to the bottom of the bowl and seat it against the friction drive.

You have to take care to apply enough pressure to keep the bowl safely in position, but not to tighten so much that you damage the bottom of the bowl with the tailstock. Also take care to ensure the tailstock is central, might take a few attempts.

Use only with low speeds and very light cuts from your gouge, preferably with a face mask also in case the bowl comes loose.

Doing it this way allows you to tidy up and/or remove the chucking recess or spigot from the bowl bottom, leaving only a small area where the tailstock supports to tidy up by hand off the lathe ( power drill and sanding pads good for that).

Sounds complicated, but with a bit of care can be done and finished before you have even got your cole jaws out of their box !

Let me know if difficult to understand and I'll try a couple of pictures later.

No such thing as silly questions, only unintelligble answers !!!

Cheers, Paul.

 

[bwlossie]

Thanks Chisel,
I understand what you are saying, but.............do you still use a live centre in the tailstock or perhaps turn a small cover which goes over the point and possibly covered in foam too?
Barry.

 

[paulm]

Meant to mention that Barry but got interrupted mid post !

Yes, I still use the live centre in the tailstock and often use a small ply button sized piece or similar to cover the point of the centre. Haven't needed to pad that bit so far but would work also I think.

Cheers, Paul.

 

[bwlossie]

Thanks Chisel, Very interesting.
Would this need a new, shaped, former every time or will one "basic" shape be enough to cover all patterns?

Barry.

 

[paulm]

One pretty much fit's all I find.

Useful to have the end furthest from the chuck a bit larger diameter than the rest though, as if it's too narrow a diameter there may be insufficient surface area in contact with the inside of the bowl to support it and/or provide sufficient friction to drive it.

Max of a couple of sizes would cover most eventuallities, one for small bowls and one for larger say, or just the one to start with and see how you go !

Cheers, Paul.