Vacuum chuck

[alex robinson]

Recently got myself an old vacuum pump for some resin stabilisation. Worked great for that, so I decided to have a go at a vacuum chuck.

I bought a rotary adapter (holdfast) for £50. I looked at vacuum chucks. They seemed excessively expensive, so decided to make one. Took a small faceplate, some MDF and a drainpipe connector. Topped with a piece of neoprene to give it a soft face for holding

 

[alex robinson]

A simple T valve controls vacuum level. So far tried several bowls with it. Hold big things really firmly and not blown through the bottom of one yet!

Not a huge amount of point to this post, other than to say if you have wondered about making one, go for it. I don't know why they aren't more common in the UK. Finishing the base of bowls is always so tedious and this makes it dead easy.

Compared with alternatives, cole jaws are very expensive and don't work with natural edges. Jam chucks always feel risky and only work with bowls than can be turned over the bed - the vacuum is great with the head swiveled. Really wish I had taken the plunge earlier!

 

[Robbo3]

Brilliant.
I had something similar but found it too long winded to set up & take down just to finish one bowl & as I'm not a production turner I would only ever have a maximum of three unfinished bowls at any time. Much quicker & easier to use a wooden friction drive, held in the chuck with a bit of foam &/or cloth for protection against marking, then bringing up the tail stock for support. That is provided you abide by the rule of always leaving the centre divot so that it is the last thing to be turned away. This method does mean that you need to clean up & finish the last little bit by hand.
This is not a dig at you, just an alternative method.

 

[Paul Hannaby]

I have a vacuum chuck and use it for a variety of things, not just reverse turning bowls. I often reverse turn bowls using a mandrel between centres and the limit of turning over the bed isn't usually an issue as my biggest lathe will do 24" over the bed.
The decent vacuum chucks (airpress, Oneway etc.) are eye wateringly expensive but should last a lifetime. I know of several people who have made their own chucks, either from wood or plastic pipes and they seem to be happy with them.
There's an article on my website you might find of interest.

There are times when a vacuum chuck won't work. Some woods are so porous the pump can't create an adequate vacuum and bowls with holes/cracks don't work too well either! However, I have managed to keep a leaky piece of wood on the vacuum chuck by putting a layer of clingfilm over the area above the chuck. This only works if you aren't cutting in the same area as the film...

 

[alex robinson]

Brilliant.
I had something similar but found it too long winded to set up & take down just to finish one bowl & as I'm not a production turner I would only ever have a maximum of three unfinished bowls at any time. Much quicker & easier to use a wooden friction drive, held in the chuck with a bit of foam &/or cloth for protection against marking, then bringing up the tail stock for support. That is provided you abide by the rule of always leaving the centre divot so that it is the last thing to be turned away. This method does mean that you need to clean up & finish the last little bit by hand.
This is not a dig at you, just an alternative method.

Pretty much everything I make is twice turned from green wood, so leaving a neat centre pin is difficult. I can also only manage a 16" bowl over the bed, so it is nice to be able to make full use of the rotating head now. Will see how annoying it is to leave on. Worst case it will just need the tube attaching each time.

I am not a professional either, but there was a craft fair at work recently so I had quite a few bowls to finish. Always good to have a deadline to focus the mind - have been meaning to try this for ages!

 

[alex robinson]

I have a vacuum chuck and use it for a variety of things, not just reverse turning bowls. I often reverse turn bowls using a mandrel between centres and the limit of turning over the bed isn't usually an issue as my biggest lathe will do 24" over the bed.
The decent vacuum chucks (airpress, Oneway etc.) are eye wateringly expensive but should last a lifetime. I know of several people who have made their own chucks, either from wood or plastic pipes and they seem to be happy with them.
There's an article on my website you might find of interest.

There are times when a vacuum chuck won't work. Some woods are so porous the pump can't create an adequate vacuum and bowls with holes/cracks don't work too well either! However, I have managed to keep a leaky piece of wood on the vacuum chuck by putting a layer of clingfilm over the area above the chuck. This only works if you aren't cutting in the same area as the film...

Your website was one of the accounts I read before making it. Many thanks - very helpful.

Not trying to claim this is anything novel, just a nudge to anyone out there like me that has been thinking about trying one. Far easier than I expected and more versatile.

Trueing up chuck recesses for green turned bowls probably going to be just as useful for me as final finishing.

It is interesting how fashions for tools vary across countries. Swivel head lathes seem more popular in Europe than the US (they all seem to have vast capacity machines), yet vacuum chucking more common there. It would make more sense for the two to go together as otherwise that maximum capacity bowl is a right pain to finish!