BALLS

[wizer]

Hi Guys

I'd like to turn some large balls. Do any of you know of a jig to do the job? I'd like to turn quite a few so I'm not keen on doing them by hand.

Any ideas?

 

[bobham]

How large is large? David Springett uses a pivoting jig in this video: http://www.youtube.com/watch?v=9scH5rMySig

I would think it could be modified to suit.

Good Luck!
Bob

 

[wizer]

cheers Bob. The sizes I was thinking would be 6" minimum, up to 12". I have been doing some research. It appears no one makes a jig like this commercially. Which I find odd.

I may make the 'simple' version David referred to in that video. Bob Chapman has plans on his website.

http://www.bobchapman.co.uk/_6__ball_jig.pdf

 

[TobyB]

Why so large, out of interest? I have used the Wivamac one which does up to 250 mm - it seems large enough to make balls for skittles games I've made, and would easily do most staircase finials, etc. What are you planning that'll need multiple 12" balls? (Pictures)

 

[Mike Wingate]

I copied a Craft Supplies jig that fitted and pivoted in the toolpost. The cosen lathe tool was bolted into the device, this was adjusted to give the diameter of the ball. It worked but I bought a Lathe copier and make balls from an MDF template.

 

[wizer]

Thanks Chaps.

Toby, no practical reason\use. Purely ornamental\artistic.

Mike, I've just had a look at the jig that Craft Supplies sell. I'm a bit confused to how it works? Surely the tool post moves in and out, as well as rotates when unlocked? Seems expensive for half a tool. I was looking at Bob Chapman's instructions where he used a top slide from a metal lathe. Might be the way to go.

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[wizer]

This one looks simple-ish

http://www.youtube.com/watch?v=oHYp353gaFA

Although my metalworking skills are Zero. I wonder if I could make it out of ply and wood? I guess the main problem with working on large balls will be the distance away from the bed bars, hence causing chatter\vibration.

 

[laird]

I presume you've seen this
http://cgi.ebay.co.uk/WOODTURNING-LATHE ... 439d975b9e
It only goes to 4", but I get the impression the seller makes them, so he might be able to extend it to 6".

 

[dannykaye]

one of these might give you ideas


http://cgi.ebay.co.uk/WOODTURNING-L...UK_Crafts_Other_Crafts_EH?hash=item439d975b9e

http://cgi.ebay.co.uk/MODEL-ENGINEE...Home_Garden_PowerTools_SM?hash=item439d91471b

http://cgi.ebay.co.uk/LATHE-BALL-TU...Home_Garden_PowerTools_SM?hash=item1c1052eb5c

I have made the first style and the important thing is to get it vertically centered at the size you want. It should be easy to make something similar that fits in the toolpost. the second one relies in a very rigid mount which might be harder, possibly plywood with steel angle reinfrcing?

 

[frugal]

There is a detailed section on making a ball turning jig in Woodturning Wizardry by David Springett. He uses his jig for cutting spheres at about 60mm diameter, but I see no reason why the design can not be scaled up.

 

[Paul.J]

Tom.
There is an article in issue No177 of Woodturning mag on making largeish balls,10"dia, for the garden,if you have it :?:

 

[wizer]

Thanks guys. I will look at all the links provided, especially laird's. Time is short atm so I'd be happy to pay a reasonable amount for an off the shelf solution.

Paul, I don't have that issue. Would you put it aside for me. If I don't get anywhere before the bash, I can have a little look when I get there.

Cheers.

 

[wizer]

So I spoke to the guy on eBay. He does make them but won't go bigger than 5" due to "cutting forces".

I found another example on Laymar Crafts. His one does 7" and he suggests going higher.

I might give making one a go and if it doesn't work out then I'll go with the eBay guy.

 

[laird]

Thanks for the feedback.

 

[TobyB]

I'd be surprised if a plywood etc solution would be strong enough - the one I've used was pretty solidly engineered (eg cutter mounted on a 30 mm diameter bit of steel) for making up to 250 mm diameter balls ...
http://www.willyvanhoutte.be/en/catalog/show_cat/447
It worked well, but I imagine you'll have a lot of distorting forces when going bigger than that, just like working a long way off the toolrest when deep hollowing, etc.

 

[wizer]

Thanks Toby. I wonder if I could have the main parts of that jig made for me.

It looks relatively simple for someone with metalworking facilities.

 

[TheTiddles]

I copied a Craft Supplies jig that fitted and pivoted in the toolpost. The cosen lathe tool was bolted into the device, this was adjusted to give the diameter of the ball. It worked but I bought a Lathe copier and make balls from an MDF template.

Hi Mike

What copier do you have and where did you get it from? There seems to be a cronic shortage of suppliers of them in Europe

Aidan

 

[jurriaan]

Ball turning jigs are well known in the German woodturning world, and since I live in between, let me give you a link for a Kugeldrehvorrichtung:

http://www.hobbyholz.de/catalog/product_info.php?cPath=357&products_id=1032

works with a center height of 12" (as I have myself, with this tool).

The tool, with a custom-made cutter, in action on my lathe:

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The product description page mentions a 440 mm ball could be turned when you have 300 mm center height. Hardcore German woodturners say that youngsters using such a tool are not real woodturners, by the way :wink: - real woodturners know how to turn a ball by hand.

 

[TobyB]

That's a serious bit of engineering isn't it! Hardcore UK turners would say you should turn balls by hand too ... and I've read how to do it, tried it, and not been very good at it. I used a jig and nieces and friends children have been very happy with the skittle sets I made them (parents seemed pleased too!) - wondering about a croquet set with turned mallets and balls ... maybe this summer?

So - whilst I know, with practice, I should be able to learn to turn a ball - I'm pleased with using a jig ...

 

[wizer]

Wow Jurriaan, That's an impressive bit of kit. 300 Euros before shipping. So it's going to end up £300+ after shipping. I'd like to investigate having it made for me in the UK. Even if I can save £100 it'd be worth it. But hopefully it can be made for much less. The raw materials shouldn't cost too much. It's just the tooling which is specialist.

Can the owners of these jigs let me know what is so specialist about those tips. Would a standard scraper not suffice?