Bowl foot sizing

[Maurice D]

When Richard was commenting on the delightful bowl by Tanzaro he said that the chuck size should not dictate the size of the foot on a bowl. This raises point I have been concerned about. I would like to turn a raised foot on a 12" bowl but only have a Nova G3 chuck with 50mm jaws. This would therefore mean the foot would not conform to the usually accepted 1/3 rule. I would appreciate some advice please.

 

[CHJ]

Maurice, you use a dovetail socket and blend the base in when you reverse the item. (or Hot Glue mount on scrap wood in the first place if you don't have depth for socket.)



Don't be too fixed about rules, appearance depends on overall shape of the bowl, depth/height of foot has as much bearing on form as diameter IMO. The Bowl that triggered the comments would have looked totaly different in profile if the small foot had been just 1 mm high.

 

[Russell]

Maurice, you could do this in 3 ways 1st is to buy bigger jaws maybe 100mm or 130mm. The 2nd is to turn your foot and then the chuck spigot which you turn off or 3rd put a recess inside the foot to hold with the jaws in expansion. Either way when you have finished the front of the bowl you can then reverse the bowl buy using a jam chuck and remove the spigot or disguise the recess to make the foot look more decorative on the underside.

 

[duncanh]

I pretty much always do the 2nd of Russell's suggestions - turn the outer shape to give the bowl shape complete with foot and add the spigot/dovetail as an extra element connected to the bottom of the foot.
You waste a little of the depth of the wood but it's usually worth it.

 

[Richard Findley]

Hi Maurice,

I usually turn a spigot, which only needs to be a few mm, then the foot of the bowl (if I want the foot bigger than the spigot, if not then you can re-turn the spigot into the foot) then shape the bowl. Right at the end of the turning I re-mount the bowl like this:

This is a disc of MDF mounted on a faceplate with a disc of router mat, the bowl is then held to it by the live centre. You only then have a tiny nib to remove by hand at the end.

I feel that this method gives you full control of the design of the bowl rather than relying on the size of your equipment. It is also cheap to do so no excusses !!! :wink:

Cheers

Richard

 

[johnny.t.]

I do them like Richard but would just like to add that you need to mark the centre of the spiggot when you first turn the back to allow you to centre it properly when you reverse it as in Richards picture. I also sometimes hold it the same way and then use gaffer tape to hold it on which allows you to finish the bottom unimpeded by the tailstock(if you do this you must take very light cuts)

JT

 

[Maurice D]

Many thanks for the advice. I will have to try using a spigot. I normally turn the base complete with foot and then re chuck to do the inside which does not require any further work on the base, but it does limit what I can do. Thanks again.