Ball ended Hex (How to machine?)

[gustafson]

I was thinking hex collet block and ball end mill but Scott is right, 2 axis from the side will work.
No CNC? On convex one concave turning tool in the lathe

 

[eKretz]

Lot's of ideas but one huge problem:
No idea of the OP's machinery or skills. Without those it's like putting a note in a bottle and casting it into the sea.

Certainly what comes to mind is an indexer or collet block and a 2-axis CNC mill. For this even a Spindex would work.

But again, without further information from the OP we are just guessing.

That's pretty much almost always the way it is here. We are all just throwing out ideas, the guy asking can pick whatever he has the ability to do.

 

[Billtodd]

Impressive lathe attachment

This is a typically inventive attachment from Eugene , for cutting polygons with a lathe.

www.practicalmachinist.com

Using a form tool , and great care ;⁠-⁠)

 

[implmex]

Hi ScottL
You wrote:
No idea of the OP's machinery or skills.

The OP has customers so I am going to guess he knows his way around a machine shop but this job has him stumped.
That leads me to believe he's been in the trade for a relatively short time and this project is complicated for him to visualize how to tackle.

If you look at the model he showed, it has other features on it that imply access to a CNC mill, and those features do not seem to faze him, so maybe he just had a brain fart about this feature...who knows!

So I'm going to assume accordingly.
If I'm wrong maybe he will chime in again.

Cheers

Marcus
www.implant-mechanix.com
www.vancouverwireedm.com

 

[mgraham1930]

Thank you every one for all of your suggestions.
I need to make approx. 50 per month.
The part goes into the main drive for a Drone.
The material is Chromium Molybdenum Ally Steel RC 38 but gets Heat treated to RC 58
When I seen it first, I thought this should be easy but it is far from easy.
I though about getting a grinding wheel made with the actual profile of the Ball end Hex Head and doing is on a grinder using an indexer but that would be ridiculously slow. I have a Tsugami MO8SY Dual spindle with Y axis and Live Tooling that has been running the same job for almost four years 10 hours a day and it looks like I am going to have to try program it and run it on this machine. I know it can be done on this machine but it is still going to be a pain in the butt.
I believe that the heads are forged on the Hex Keys.
I don't claim to be a master machinist but I have been in the business almost thirty years and have shipped 7.3 million parts to my customers. These include Boeing, AirBus, Lockheed, Raytheon and many more. Our Quality rating is currently 99.98% and has not fallen below that number for several years.
I would like to think I know what I am doing but I have my days. This is not an easy part to make as a production part.
Thank you everyone and I will let you know how it worked out and hopefully post a few pictures.

 

[eKretz]

They aren't forged in quantity production, they're polygonal turned... It's a matter of a few seconds work. Probably not going to make sense for those lower quantities though.

 

[Garwood]

Thank you every one for all of your suggestions.
I need to make approx. 50 per month.
The part goes into the main drive for a Drone.
The material is Chromium Molybdenum Ally Steel RC 38 but gets Heat treated to RC 58
When I seen it first, I thought this should be easy but it is far from easy.
I though about getting a grinding wheel made with the actual profile of the Ball end Hex Head and doing is on a grinder using an indexer but that would be ridiculously slow. I have a Tsugami MO8SY Dual spindle with Y axis and Live Tooling that has been running the same job for almost four years 10 hours a day and it looks like I am going to have to try program it and run it on this machine. I know it can be done on this machine but it is still going to be a pain in the butt.
I believe that the heads are forged on the Hex Keys.
I don't claim to be a master machinist but I have been in the business almost thirty years and have shipped 7.3 million parts to my customers. These include Boeing, AirBus, Lockheed, Raytheon and many more. Our Quality rating is currently 99.98% and has not fallen below that number for several years.
I would like to think I know what I am doing but I have my days. This is not an easy part to make as a production part.
Thank you everyone and I will let you know how it worked out and hopefully post a few pictures.

I have not shipped 7.3 million parts, but I can just write 4140PH instead of fluffing it up to sound exotic.

That part really doesn't look challenging.

 

[magneticanomaly]

End mill with radiused corners, driven by a live spindle mouned on a ball-turning attachment on a lathe with capability to index and lock spindle.

Chuck blank in lathe, lock at first index position

With tool swung all the way to the left and tool spinning, advance crosslide to full depth.

Swing to the right, cutting ball profile, ending with endmill axis parllel to work spindle axis

Index work spindle to second position

Swing cutter back to starting position

Withdraw crossslide to clear work,

Index to third position
SWing right
Index to fourth
Swing left, withdraw, etc

 

[implmex]

Hi again mgraham1930;
As others have remarked, if you have a live tooled lathe, this part should really not be that hard to make.
You can choose to use a radially oriented small endmill or axially oriented form tool.
The axially oriented tool makes for a simpler toolpath but a more expensive tool.
Since it's a Y axis lathe, it is ideal for this job...if it was me I'd just use a radially oriented endmill (cutter axis parallel to X axis) and walk around the curved profile from root to root using Y and Z, three times. indexing 60 degrees between passes, just like memphisjed outlined in post #18.

The cutters are cheap standards and should last a long time.
You should be able to make a hex ball in under two minutes, and if you're only making fifty parts a month, it's not even worth having a conversation about strategies to improve that processing time.

If you need to take more material than you think the cutter can take in one bite, you can plunge rough the roots of the ball, and knock off the worst of the corners before you go back and walk around the profile to finish it.

The hardest part is programming the cutter path, and that shouldn't tax you very much since you seem to have ample experience programming and running your machine.
Run it as a sub you can call after every index, to simplify your programming.

Cheers

Marcus
www.implant-mechanix.com
www.vancouverwireedm.com

 

[Corn]

Here`s shown @1:23 how they make the ball end for hex head.
Turning hex head

 

[eKretz]

Here`s shown @1:23 how they make the ball end for hex head.
Turning hex head

Polygonal turning... Probably not gonna fly in this case. Quantity is pretty low for expensive specialized tooling. Marcus has got the best solution for this case I think.

 

[Screwmachine]

They aren't forged in quantity production, they're polygonal turned... It's a matter of a few seconds work. Probably not going to make sense for those lower quantities though.

I knew I had seen it being done on PB Swiss hex keys, wouldn't you know it was an episode of How It's Made. Around 1:20 they show it. Like you said, a few seconds.

 

[michiganbuck]

One could dress the radius and a short flat and form to a grinding wheel and long travel grind off the index if that was already made or out on a spin index.
Yes , rough a little oversized ball on a lathe first to save time.

Not long ago there was a PM thread using a whacker rotating tool bit and a timed lathe for making such items..I think it was that Russin guy who made the thread.

 

[eKretz]

Not long ago there was a PM thread using a whacker rotating tool bit and a timed lathe for making such items..I think it was that Russin guy who made the thread.

Yup, that is polygonal turning also. He might have a hard time forming the desired contour unless he used a form tool though. Way too much work for 50 parts a month.

 

[AD Design]

I knew I had seen it being done on PB Swiss hex keys, wouldn't you know it was an episode of How It's Made. Around 1:20 they show it. Like you said, a few seconds.

-I was the point man in the ball driver project for Eklind Tool in the mid 90's. The process in the video that creates the ball itself is similar, nothing else is. The spindle speed for both the cutter AND the workpiece have to be timed to have the correct relationship that produces a "flat" or it will produce something similar to a screw extractor, I have a few examples in a toolbox somewhere. The remaining profile of the ball and neck can be easily programmed in the two axis movements in the equipment the OP already has IMO.

For the small quantities the OP requires per month I don't see why purchasing existing ball drivers couldn't done if it's a stock size, perhaps changing the assembly to accept them. Perhaps contacting one of the makers of ball drivers to run a batch with the desired profile would be feasible. If it's an already existing size/profile it's a simple matter of bleeding off a production run.

As for grinding them with an indexer on a surface grinder, that's what I did to create the reference prototypes and gauges before production machinery was made. It didn't take me very long to do this but everybody has a different notion of time vs. money.

 

[doug925]

What about a custom ground profile (form) mill? Mill the Hex OD with a standard cutter, then clean the ball end with a form cutter.

 

[just Dave]

They aren't forged in quantity production, they're polygonal turned... It's a matter of a few seconds work. Probably not going to make sense for those lower quantities though.

As the polygonal turning is happening (Bondus video ) is the cutter moving towards and away from the spindle to maintain hex shape?
Pardon my ignorance, I’m an old manual Man.

 

[michiganbuck]

Easy on a CNC grinder with a profile dresser

 

[eKretz]

As the polygonal turning is happening (Bondus video ) is the cutter moving towards and away from the spindle to maintain hex shape?
Pardon my ignorance, I’m an old manual Man.

It sweeps through in an arc actually. You can get a better idea of the mechanics of the process with this video:

 

[just Dave]

It sweeps through in an arc actually. You can get a better idea of the mechanics of the process with this video:

This is cool ,some next level thinking. Thanks
I would call it a shaper cut turning in response to the videographers question?