[ngwanhoe]

How to manually mill a double ball end (refer to link picture) with a vertical milling machine.

I have a rotary table.

1) What tools needed?
2) Steps?
3) Any picture instructions?

Thanks a lot for advice.

[jalessi]

Ngwanhoe,

There are a lot of YouTube video's that may inspire a idea.

[nomedia="http://www.youtube.com/watch?v=CZxuM6V7Ijc&playnext=1&list=PLC228FBAE81E4 F35A&index=3"]YouTube - Emco pc mill 50 turns into a lathe[/nomedia]

Jeff...

[ngwanhoe]

Ngwanhoe,

There are a lot of YouTube video's that may inspire a idea.

YouTube - Emco pc mill 50 turns into a lathe

Jeff...

Thanks Jeff,

Unfortunately I don't have the luxuries of a CNC Mill. I only have a benchtop vertical manual milling machine.

[SORCHEROR]

put the rod in the collet of your mill and make a radius tool and put the tool in your mill vise,basically turn your mill into as lathe

[jalessi]

Ngwanhoe,

I completely understand, the idea of using the mill as a lathe was the purpose of the video.

Sorcheror's suggestion is a step further in that direction.

Good luck with your project.

Jeff...

[Geof]

Rotary table and manual vertical mill, making a sphere is dead simple.

Have a look at this thread particularly the first three pictures in Post #10. It should be self explanatory.

http://www.cnczone.com/forums/genera...ere_stick.html

[ngwanhoe]

Thanks Jeff and Sorcherer,

I was having that idea too. I saw some was using a metal pipe to turn the ball into a perfect round. Just checking is there other ideas.

yes I will attach the rod to the collet and attach the tools to the rotary table vertically.

That should work.

[ErnieD]

Hi,

Years ago I read in one of the Practical Ideas in American Machinist mag about a method where by you mount a rotary table at an angle to the table of your mill. Place the stock in the chuck on the rotary table. Mount an adjustable boring head in the spindle of the mill with the cutting edge of the bar to the inside and set to the size of the ball you want. You center everything and feed the spindle down while rotating the table and you will get a ball.

If you can find any archives on Practical Ideas it shows a picture of the setup. I used to tear these out of the magazine and save them. I still have them somewhere. The time frame that I am thing was about was from 1962 to 1980.

ErnieD

[ngwanhoe]

I was thinking setting the rotary table vertically with a lathe cutter facing the center of the rotary table, attahced the rod to the spindle and turn the rotary table so that the tip of the cutter goes up and down on a curve to cut the rod.

Thanks everyone for great ideas

[Geof]

That will work but it is much easier to align things by mounting the part on the rotary table and have the tool in the spindle as ErnieD describes. I have used both ways to make spheres on both mill and lathe and the most accurate way is to generate it with the tool in the spindle and the work on the rotary table.

[SORCHEROR]

i agree with Geof,for accuracy and finish is best that way,i just thought if he had a grinder and made a form tool that would be easiest for him,personally,if i had to make more than a few,i would farm it out to a cnc lathe

[fizzissist]

You'll find how to do this and a ton of other things in The Machinist's Bedside Reader by Guy Lautard. There was 3 in the series last time I looked.

Any serious machinist, hobby or pro should have these..if for no other reason that out of respect for the guys that have done it the hard way, and to keep the craft alive.

[ngwanhoe]

i agree with Geof,for accuracy and finish is best that way,i just thought if he had a grinder and made a form tool that would be easiest for him,personally,if i had to make more than a few,i would farm it out to a cnc lathe

I have a grinder. Any picture of the tools or geometri?

[Geof]

I will stick my neck out and say it; using a form tool to make a ball on a small diameter neck like that is asking for problems. Either bad chatter or the neck breaking off.

[fizzissist]

I will stick my neck out and say it; using a form tool to make a ball on a small diameter neck like that is asking for problems. Either bad chatter or the neck breaking off.

....Sticking neck out!?! Geof, you crack me up.

Plunge forming is just begging for problems...the higher the surface area, the more pressure on the neck material supporting the ball. That's why generating with a profile tool or rotating the tool and work simultaneously is preferred.

But there is another option, and that is skiving, where you plunge cut with a form-ground tool that sits off center, cutting progressively and supporting the work with the equivalent of a steady rest built into the tool holder.

It's often used in screw machines, where it gives good tolerances, good finishes, and good tool life. It's great where there's a big difference in relative diameters in the part.

Here's a description:
The Forgotten Art Of Skiving : Production Machining

[ngwanhoe]

Wow you guys are really masters of trade. Willing to stick your head out!! ha.ha. All of you guys technics seems complicated to me as I am a novice in this. The only thing I understand is doing it like on a lathe which is simple theory and setup. If you guys have any write up or pictures in steps, it would be great an very much appreciated.

Cheers

[fizzissist]

Wow you guys are really masters of trade. Willing to stick your head out!! ha.ha. All of you guys technics seems complicated to me as I am a novice in this. The only thing I understand is doing it like on a lathe which is simple theory and setup. If you guys have any write up or pictures in steps, it would be great an very much appreciated.

Cheers

What's ironic is that the innovations usually come from the guys who don't have the equipment, or the skills, to do it the conventional way and have to make do with what they've got.

[ngwanhoe]

Lets say I use a hollow mill bits attached to the spindle and tilt it to 45deg or somthing like that and the work piece attached to rotary table horizontally, what size of the hollow mill should I get?

Thanks.

[brewzz]

I have done this many times.You tilt the mill head ,and use a boring head with a sharp pointed 45 deg cutter.Place the workpiece,centered on the rotary table,adjust the boring head to cross centerline of the top of the workpiece and start cranking.I have a formula for the angle and dia., which makes a difference on the radius generated.It's at work somewhere,but I hope this helps.
John Stearns

[ngwanhoe]

I have done this many times.You tilt the mill head ,and use a boring head with a sharp pointed 45 deg cutter.Place the workpiece,centered on the rotary table,adjust the boring head to cross centerline of the top of the workpiece and start cranking.I have a formula for the angle and dia., which makes a difference on the radius generated.It's at work somewhere,but I hope this helps.
John Stearns

I am trying to mill a ball knob 25mm or 1 inch diameter and have to do a dozen of them.
1) Is using the boring head faster than hollow cutter?
2) Can you please let me know the formula?
3) Do you have any pictures?

Thanks
A lots