sphere turning jig

[marcros]

I am interested in asking for a sphere turning jig for christmas. They are so tactile and make you want to touch them/pick them up

There seem to be numerous jigs available, from http://www.ebay.co.uk/itm/EASY-PRO-WOOD ... SwiCRUcKin which I believe is used by Carl Jacobson (certainly looks similar on youtube), to the one that I saw on the Simon Hope stand at Harrogate.

Has anybody any thoughts on them. I know that the hope one has a carbide cutter on it, but I am sure that the eBay one could be adapted.

Ultimately, I would like to turn huge spheres- i really like them. For now, I am using a jet mini, and have limited sized timber supply. I suspect that my limit for a sphere at the moment will be 6" at most, and more likely 4".

My priority would be setup time- to get started on turning a cylinder to a sphere as quickly as possible and assume a batch quantity of one.

 

[Dalboy]

Spheres are not hard to turn free hand and once you have done a few they become easier to do, use a cardboard template helps. This is one I did free hand a while ago and the ball is 4"

 

[marcros]

very nice!

I still fancy the lazy approach though!

 

[monkeybiter]

It's easy to build yourself one, I made one out of ply for a plate to clamp down to the lathe bed and a block of 2x3 with a groove and a top clamp to hold one of my turning gouges.
It's just about holding a cutting edge at centre height and allowing it to rotate about a vertical axis in line with the spindle axis; all of which you know. Just saying, it's easy to make one.

 

[Sheptonphil]

I purchased the easy pro jig last week (the exact one you linked).

It arrived next day, perfect service

Setting the jig to your lathe takes 10 minutes, and only needs doing once.

As a first test I had a length of 4" fence post. I cut it to approx 7" long, put it between centres, and turned a chuck tenon on one end.

Mounted then in the chuck with tail stock support, a line was marked a fraction over 2" and 4" from the tail end

Using a spindle gouge take the corners off the tail end rounding slightly to the live centre. Make a grove cut at the head end. Change over to the jig and taking light cuts shape only the tail end, removing tail support to complete the end cut. Allow sufficient when markin up to remove the dented end of the live centre. Replace live point with a cushioned cone centre to prevent marking.

Cut the head end down to 8mm or so, sand and finish the sphere at this point. Take the head end down to 3-4mm and with hand support, part off on a curve with a thin parting tool.

Final finishing between a pair of cone centres (home made)

A pretty near perfect sphere in 10 to 15 minutes of jig work. Second and third spheres were in sizes 2-4 inch and still 10 mins or so.

I've also made Christmas angels now with spherical head and tapered body, wings cut on the bandsaw. Look far better than my freehand heads.

Yes, I have made a sphere freehand, but it took almost an hour and a quarter of constantly rotating it between cups to get it right.

This makes life so much easier, and more enjoyable making other projects. I have been asked to turn a 5" Oak sphere (wood supplied) with a 3/4" dia spigot left attached to replace a split sphere top on a large staircase newel post. I wouldn't have been confident without the jig as it has to be cut in one plane and can't be rotated between cup centres (because of the spigot left on) to get the sphere perfect. The size can be controlled within a mm or two. Getting £20 for it, so jig a third paid for. \/

Loving this jig. Although states 150mm capacity, I don't think it will turn more than 140mm

Phil

 

[marcros]

thanks phil.

 

[Rhossydd]

My priority would be setup time- to get started on turning a cylinder to a sphere as quickly as possible and assume a batch quantity of one.

Why the rush if you're only working on 'one offs' ?

From what I can see the jig makes sense if you're making lots of spheres, but might prove an expensive indulgence for single projects.

It wouldn't be difficult to make a jig for final finishing of spheres, with some thought it could be expandable to cope with a wider range of sizes than the jig you mention which sounds like it won't cope with your ambitions for future work.

 

[YewTube]

I am interested in asking for a sphere turning jig for christmas. They are so tactile and make you want to touch them/pick them up

Well you are easy to buy for and not going to break the bank.

http://www.davidreedsmith.com/Articles/ShadowSphereJig/ShadowSphereJig.htm

Merry Christmas

Bill

 

[Wildman]

I am interested in asking for a sphere turning jig for christmas. They are so tactile and make you want to touch them/pick them up

Well you are easy to buy for and not going to break the bank.

http://www.davidreedsmith.com/Articles/ShadowSphereJig/ShadowSphereJig.htm

Merry Christmas

Bill

clever idea