"Hannums" ball turner

[Dan_the_Chemist]

I'm calling it Hannums ball turner because I bought it from his estate. He may or may not have made it.

Somebody asked me to take it apart, so I did. If you want pictures I can post them, but I got carried away and did a CAD design in Fusion 360. The picture is the exploded version, minus a few grub screws and the turning tool. If anybody wants the Fusion project I'll figure out how to make it publically available and you can have it.

[BCRider]

Well, that's certainly a nice simple and straight forward ball turner. Thanks for the time to make up the project and sharing it.

[flathead4]

With no height adjustment and the angled slot for the tool, it looks purpose built for that lathe and hand ground HSS. Interesting take, though.

Tom

[Ohio Mike]

The base would be machined to the proper height to get you close and the angled slot would be how you would get on center. I'd like to see a photo or two of the original when you get a chance.

[Dan_the_Chemist]

With no height adjustment and the angled slot for the tool, it looks purpose built for that lathe and hand ground HSS. Interesting take, though.

Tom

That is the same conclusion I am coming to, although there is some minimal adjustment on the hieght of the tool bit tip. You just play on sliding the tool forward and back, and then slide the tool holder forward and back... bit of a pain, but it works.

When I took it out and checked it against my lathe I found the following:

If I leave the compound rest on my cross slide, the tool tip is 3/4" above center.
If I take the compound rest off of the cross slide, the tool tip is about 5/16'ths below center.

So, while it's a bit of a PITA to remove the compound slide, I've decided to make an adapter that will go in the place of the compound slide. If I planned on making a lot of balls I might rebuild the bottom part in the existing tool (the salmon? colored part). I would make that so it fit into the slot on the compound slide. But since I figure I'll not be using this more than a few times a year, it's okay if it takes an additional 15 minutes to dismount/remount the compound slide. Plus, it gives me a chance to clean under the compound.


The adapter will be simple... it's just a plate that sits on the cross feed. The compound slide has a peg that fits into a hole on top of the cross feed, and two holes that fit over studs on the cross feed. So, I basically reproduce that part. Then I make a 1.49 post with a groove that the grub screws in the bottom of the ball turning tool will capture.

As per height adjustment... I'm not too thrilled with having to slide the lathe tool back and forth to change the hieght, and then move the entire holder to adjust the distance of tool-tip to rotational centerline. I'll give it a go. If it turns out that I want more vertical distance, I'll make a few shims to put under the tool carrier. Then the back and forth will only be used for fine adjustment.





(PS... this is just a rough sketch. Now I have to go out and measure everything on the lathe carefully and adjust the dimensions.)

[CCWKen]

The hex point looks like it serves the purpose of setting the tool height as well as the radius. I'm guessing that's removed afterword. As far as machine center height, that would vary for all so yes, the tool would be machine specific. If I'm gong to build one, I'd build it for MY machine.

The problem I ran into with this type of tool is the necessity for stock extension from the chuck. Mine won't go under the chuck so the material must hang out quite a ways. A collet chuck might help but I haven't had a chance to try mine.

[Dan_the_Chemist]

The base would be machined to the proper height to get you close and the angled slot would be how you would get on center. I'd like to see a photo or two of the original when you get a chance.

Your wish is my command (especially when I have the photos already to hand).

[Dan_the_Chemist]

The hex point looks like it serves the purpose of setting the tool height as well as the radius. I'm guessing that's removed afterword. As far as machine center height, that would vary for all so yes, the tool would be machine specific. If I'm gong to build one, I'd build it for MY machine.

The problem I ran into with this type of tool is the necessity for stock extension from the chuck. Mine won't go under the chuck so the material must hang out quite a ways. A collet chuck might help but I haven't had a chance to try mine.

Yes, the hex point is a snug but sliding fit.

Ah-HA... I looked at a lot of YouTube videos to see if I could see this type of ball turner in use, and a lot of those videos used collet chucks. Your suggestion makes sense and explains why the use of the collet seemed to be more common than on "normal" projects.

[elf]

If anybody wants the Fusion project I'll figure out how to make it publically available and you can have it.

Right click on the file in the Fusion 360 Data Panel. Select 'Share Public Link'. When I share links like this, I usually make a copy, then share the copy. This way I can edit the original without making the changes public.

[Dan_the_Chemist]

I finished the adapter and spent a couple of hours using this dingus.

Let me frame my review by giving you an idea of how many ball turners I've used in the past. ZERO. So, take this "review" with a grain of salt.

It's easy to use, and a PITA.

I used the adapter to mount the ball turner where the compound slide normally is attached. I put some 1" aluminum round stock in the lathe, and made a ball. Actually, made about 3/4 of a ball. Then I noticed the first problem. I'd have to demount the ball turner and put the compound slide in place to part it off, or to turn the rest of the handle. I used a hack saw instead, so the ball looks like it was hacksawed off. Not so happy with that.

Then I went to try another ball. The tool was too close to the chuck so I had to stick more out. The amount of stick out required is large. Then I ran into another problem. I had hacksawed off the ball, but the remaining bit wasn't really good for the next ball. So, I had to hacksaw off more. I'm starting to miss the compound slide and the QCTP.

The first time there had been a little nipple on the end. The lathe tool tip had been a little low. So, I spent some time adjusting the height of the tip. Then I had to slide the holder back to get the same radius. I inadvertantly turned the holder a little so that the tip was no longer over the center line. This turned a flattened oval. Okay, now I can turn spheres or oblate ovoids... So, hacksaw and bother, and I play with it. I can get some pretty oval shapes... But getting it really spherical is a bit of a PITA. It has to be very carefully aligned, and that means the tip height, the distance, and the center line.

Plus, not having hte QCTP available is a serious PITA.

I spent some time playing with putting shims under the cutting tool. That worked better than using stickout to adjust the height. Too much stickout and I was getting chatter.

CONCLUSION

Well, it's the best ball turning tool I have. It's the only one. It works, but it's fiddly. It's also a pain to have to remove the compound to use it. It requires a lot of work stick out. I'm not sure if I'll bother to make a different one, but that's only because I don't see myself making many balls and handles. If I were going to do so I'd probably make a different style and drop this one on eBay.

[lynnl]

......

The first time there had been a little nipple on the end. The lathe tool tip had been a little low. So, I spent some time adjusting the height of the tip. Then I had to slide the holder back to get the same radius. I inadvertantly turned the holder a little so that the tip was no longer over the center line. This turned a flattened oval. Okay, now I can turn spheres or oblate ovoids... So, hacksaw and bother, and I play with it. I can get some pretty oval shapes... But getting it really spherical is a bit of a PITA. It has to be very carefully aligned, and that means the tip height, the distance, and the center line.

Well, you're the owner of exactly one more ball turner than I am, and in fact, one more than I have ever used. But it seems to me many, or maybe most, of the problems you cite are going to be part of any ball turning exercise. Though probably all of the alignment and so forth might be more, or less, convenient with some devices than others.

[Moxiedad2001]

In all essential design elements, if not exactly in their execution, that is identical to the MLA-13 ball turner by Andy Lofquist (Metal Lathe Accessories). The "hex point" is used for centering the cross slide in the Y axis and for setting the radius of the swing against the point of the cutter, which is held in that greenish part (is that what they call chartreuse?). The ball turner mounts directly to the cross slide and must be machined (or adapted) to put the tool at center height, though some adjustment is obviously possible by sliding the cutter forward or back. The MLA-13 kit is still available from Andy, but his web site appears to be down right now.

[Moxiedad2001]

I should add that Andy's version is a lot more elegant. I expect that he is the original designer. By the way, Dan, I see that you figured it out on your own. But most of your frustrations are common to any ball turner.

[mattthemuppet]

one solution to some of those ball turner woes is to make/ use a boring head based one that mounts on a QCTP. Still fiddly as to use, but easier to swap out for other tools. I don't think it requirs as much work stick out either, but don't have any firm data on that.

[J Tiers]

I finished the adapter and spent a couple of hours using this dingus.

Let me frame my review by giving you an idea of how many ball turners I've used in the past. ZERO. So, take this "review" with a grain of salt.

It's easy to use, and a PITA.

I........

Then I went to try another ball. The tool was too close to the chuck so I had to stick more out. The amount of stick out required is large. Then I ran into another problem. I had hacksawed off the ball, but the remaining bit wasn't really good for the next ball. So, I had to hacksaw off more. I'm starting to miss the compound slide and the QCTP.

The first time there had been a little nipple on the end. The lathe tool tip had been a little low. So, I spent some time adjusting the height of the tip. Then I had to slide the holder back to get the same radius. I inadvertantly turned the holder a little so that the tip was no longer over the center line. This turned a flattened oval. Okay, now I can turn spheres or oblate ovoids... So, hacksaw and bother, and I play with it. I can get some pretty oval shapes... But getting it really spherical is a bit of a PITA. It has to be very carefully aligned, and that means the tip height, the distance, and the center line.

Plus, not having hte QCTP available is a serious PITA.

I spent some time playing with putting shims under the cutting tool. That worked better than using stickout to adjust the height. Too much stickout and I was getting chatter.

....

Do you not do much of the adjustment by sliding the entire holder in and out and holding with the two screws? That looks to be the intended adjustment means for diameter, etc, with the angled tool slot for getting it right on center despite grind variations etc.

The thickness of the "attached base" and added base would bring it to center in a general way, to be adjusted finally by the angle.

I see it being set up on center with the angled slot, then the holder section moved in and out to set the radius.