A new ball/sphere cutter design - no mill required

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kquiggle

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As I am just getting into home machining, I don't (yet) have a mill. I wanted to build a ball/sphere cutting tool for my mini-lathe, but when I searched for existing plans, they all required a mill to build. Consequently, I created my own design for tool which could be built using the tools I had available. No doubt there is room for improvement in the design - however, it does work, and I'd like to share it with others who may be similarly situated. Also, I'm sure the many experienced people on this site can make useful suggestions.

FYI: The tool locks onto the compound rest with two cam locks. The large brass adjustment screw is used to adjust the cutting radius. The ball end on the handle was cut using the tool.

IMG_20120714_155701.jpg
 
Interesting design, it gave me some ideas for mine. There is no screw or something else to hold the toolpost firmly after setting the radius?

Thanks for posting

Roberto
 
Interesting design, it gave me some ideas for mine. There is no screw or something else to hold the toolpost firmly after setting the radius?

Thanks for posting

Roberto

The toolpost is machined "long" below the screw; I tighten down the brackets holding the adjustment screw and this pulls the tool down firmly against the plate. See my blog for a lot more detail and build plans:

http://academy-of-lagado.blogspot.com/2012/07/radiusball-turning-tool-no-mill-required.html

http://academy-of-lagado.blogspot.com/2012/07/radiusball-turning-tool-building-tool.html

I have some ideas for an improved design, so I may build a new version one of these days.
 
Nice work, Kquiggle! I like the way you think.

Chuck
 
Great little gadget I might build one myself. Has Smokey approved the plans yet

Regards Mark
 
The toolpost is machined "long" below the screw; I tighten down the brackets holding the adjustment screw and this pulls the tool down firmly against the plate.

thanks kquiggle
 
Recess the screw into a dovetail slot and add a brass gibb and you have one of these: http://lepton.com/metal/ball_turner.html

You need a mill a make the dovetail slot, and I don't have a mill yet (need to get a few more quarters in the piggy-bank). A critical design criteria for me was "no mill required."

An additional benefit of not having a slotted tool holder is that the base sits lower on the cross slide which makes for better clearance under the chuck. This might be improved still further by moving the point of rotation forward (instead of centered) on the top plate.
 
As I am just getting into home machining, I don't (yet) have a mill. I wanted to build a ball/sphere cutting tool for my mini-lathe, but when I searched for existing plans, they all required a mill to build. Consequently, I created my own design for tool which could be built using the tools I had available. No doubt there is room for improvement in the design - however, it does work, and I'd like to share it with others who may be similarly situated. Also, I'm sure the many experienced people on this site can make useful suggestions.

FYI: The tool locks onto the compound rest with two cam locks. The large brass adjustment screw is used to adjust the cutting radius. The ball end on the handle was cut eusing the tool.

There was also an excellent internal and external ball turning attachment that was published in the home shop machinist, which fits to the lathe bed and is positioned lengthwise by a link rod which is attached to the saddle. The work head spindle mounted on a double ball race one of which is a tapered roller race. It has a worm and wheel drive to wind the tool holder around to the required position. The tool holder is attached to a double slide (x and Y) so that the tool can be positioned to machine an internal or an external spherical radius. I made one of these units and have used it extensively with excellent results. I will look through my set of magazines and post the exact copies later.
Rob
 
Not sure why but the web page is down.

Curious story behind that. In the meanwhile, the same information is on my old blog:

http://academy-of-lagado.blogspot.com/2012/07/radiusball-turning-tool-building-tool.html

Here's the curious story (this is not about machining, but I think it's relevant to members who want to publish on the web about their efforts): I moved the information from google Blogger to google Sites because I wanted the flexibility of a web page. The new website was working fine for a while, and then google suspended it for "violation of terms of Service". . .! I note emphatically that I did not violate terms of service in any way that I can see (but google won't tell you why you got suspended, so who knows?). I think a google web-bot just flagged something erroneously. I have appealed the suspension so hopefully it will be back up in a few days - if not, I'll move to an alternative. I may move anyway, because I don't want to be subject to the whims of a google-bot.

Now here is the really funny part: I was in the process of adding a new article about a nut driver - you know - for starting nuts on lathe chuck studs. What do you suppose the google bot found offensive about that?
 
Now here is the really funny part: I was in the process of adding a new article about a nut driver - you know - for starting nuts on lathe chuck studs. What do you suppose the google bot found offensive about that?
Hi Kquiggle

To us Nuts are an essential part of our hobby a removable fixing we would find hard to do without.

To a squirrel they are, well, lunch.

To some they are a slang term for for an intimate part of male anatomy. (as politely as I can put it, please don't take offence, none was meant)
it may be this interpretation, whilst totally incorrect, that it didn't like. I am surprised it didn't object to the word "balls" though, on the same grounds.

I am right with you on this one, some of these filter bots can be a real nuisance and being automated you can't argue with them. Their decision is final even if its completely wrong.

We have reached the stage now where bots are fighting each other Spam bots generating unwanted rubbish and filter bots removing it. Net end result vast amounts of internet traffic but no actual information being transferred, wanted or unwanted.

It's a crazy situation, but I agree with you it's pretty funny, It's the only way to look at it without driving yourself, well, nuts!

Regards Mark
 
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I'm having a similar problem with a net nanny that rejects the word "crack" and since we are in the welding game its a topic that comes up in such things as welding cracks etc.

The server has requested we use another word. AAAARRRGGGHHH

My bank also has an overly prissy net nanny that in its wisdom bins any "dirty" communications without notifying either the server or the recipient.

I have now put the cat among the pigeons by filing a freedom of information request (on the grounds that this is used to censor my communications with the bank) for the bank to issue me with a complete list of all the rude and smutty words it deems offensive - can you imagine a bank letterhead with a list of such words - WHHHEEEEEE - fun..fun...fun.

I would encourage you to do the same.....

Regards,
Ken
 
It appears that my website has been "un-banned." I removed the page about the nut starter - so maybe that was the trigger; I'll never know because google never explains, and the site went back up with no notice of any kind.

Because all of us here are so dependent on the Internet to share information and carry on a discussion, I think it is important to this site to be aware of this issue, although it is not directly about machining.

Ken - I wish you luck with your bank, but you might better consider moving to another bank or credit union (do they have those in SA?). It would be pointless for me to battle google - the law (and money) is all on their side on this. I knew this when I went with google Sites, but I foolishly though that because I was completely on the up and up and not controversial, it would not matter. But I didn't bargain on a badly coded google-bot, or rather, I failed to consider that google would prefer to kill the innocent rather than run a risk to their business. This is the point we all need to keep in mind with respect to "free" services - sometimes the price is too high.

For this reason, I have decided to move away from google Sites. I'm going to take my time looking at some alternatives, but I think I will move in the next six months or so. I urge others contemplating a web site to keep these concerns in mind.
 
There was also an excellent internal and external ball turning attachment that was published in the home shop machinist, which fits to the lathe bed and is positioned lengthwise by a link rod which is attached to the saddle. The work head spindle mounted on a double ball race one of which is a tapered roller race. It has a worm and wheel drive to wind the tool holder around to the required position. The tool holder is attached to a double slide (x and Y) so that the tool can be positioned to machine an internal or an external spherical radius. I made one of these units and have used it extensively with excellent results. I will look through my set of magazines and post the exact copies later.
Rob

I am wondering if your ball turning attachment is from the plans by Glenn Wilson? I gave away years of Home Shop Machinist magazines. So can't go back and reference it. At my age I'm starting to reduce the things I no longer need. Glen Wilson contributed many articles to HSM over the years. He was a good friend of mine. He had the inventive mind of a genius. Unfortunately Glenn passed away about a year ago. He was also the originator of the Colorado Model Engineering Club. I had been in his shop many times and was always fascinated. I may be mistaken but your description sounds like his plan.
 
Kquiggle

Your website is indeed back up and very interesting. I like your postbox It would sure give the postie a fright on a dark winter morning.

I, like you, and I suspect many others, have been very wary of Google of late but mainly over their data gathering activities, perfectly legal, but not very morally responsible in my view. Google has changed much over the years and for the worse, it is now just a huge money making machine and I for one don't trust them.

Because all of us here are so dependent on the Internet to share information and carry on a discussion, I think it is important to this site to be aware of this issue, although it is not directly about machining.

Quite so

Ken

F.O.I. request, should make some interesting reading at least, but whether it actually does any good is doubtful. We all know what dinosaurs banks can be. Such censorship (as you rightly call it) in bank communications could potentially be very dangerous.

I have seen some dye pen N.D.T. spray whose trade name was "Crack Sniffer" wonder what your bot would make of that. It caused some amusement amongst us young apprentices at the time.

Regards Mark
 
G'day Mark
Yes the ball turning attachment was designed by Glenn L Wilson.
It was in Volume 11 number 4 and 5.
I have used it many times making hobby work as well medical equipment including an eye vice and every time it worked perfectly.
Rob.
 
Back to G**gle. When I was in college I got interested in rockets. So I giggled "Rocket models" among other things. You Would be amazed what they let show up. And I was a lot younger then. I think they may have blocked that site.
 

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