[ngwanhoe]

Hi is there anyway that I can mill threads (female and male) with a manual milling machine?

Infos
40mm diameter female and 40mm diameter male side.

[Ed from NY]

Well, you can not circle around the part like with a CNC mill. If you use a rotary table or if you put the part on the spindle there is no way to synchronize the rotation with the Z-feed. The only thing I can think of is if you can rotate and advance your part against the cutting tool with some sort of jig driven by a screw of the same lead... the jig would rotate the part and feed it at the said lead. If you can make that rigid/precise enough it might work, but you probably would need an even wider screw/thread driving the jig which makes the whole thing not very likely.

[Kiwi]

Post withdrawn.

[ngwanhoe]

If the full depth of thread is cut with one pass, the Z feed does not need to be in sync with the rotation of the rotary table.

What kind of tool do that?

What you meen is attached the special tools to the spindle and rotate the work on the rotary table around the tool?

[M250cnc]

What kind of tool do that?

What you meen is attached the special tools to the spindle and rotate the work on the rotary table around the tool?

Ed is correct the Z has to move in sync with the rotary table.

The only way to accomplish this is to connect the rotary table via gearing "THE CORRECT GEARING" so as you turn the rotary table the Z moves in tandem.

This was commonly used on dividing heads geared to the X axis on milling machines.

With CNC you don't even need the RT as the CAM will interpolate the XY & Z

With Kiwi's method all you will achieve a set of grooves, not a thread.

Phil

[Kiwi]

What kind of tool do that?

Single tip thread cutter.

What you meen is attached the special tools to the spindle and rotate the work on the rotary table around the tool?

Have the part being rotated by motorized rotary table at a known speed.
And the cutter rotating in the spindle, traveling down the side of the part at a set automatic feed rate to suit the pitch.

[M250cnc]

Have the part being rotated by motorized rotary table at a known speed.
And the cutter rotating in the spindle, traveling down the side of the part at a set automatic feed rate to suit the pitch.

Eureka

A request for a how to on a MANUAL MILL

Kit needed a MOTORIZED Rotary table with a known speed, and a manual mill with an infinitely adjustable precision Z axis feed

Phil

[awemawson]

Encoder on the spindle. Stepper motor on the rotary table. Electronics divider between the two as per John Stevensons horizontal mill used to cut gears. Set the downfeed at a suitable rate and make sure your maths is right in the divider!

[Geof]

Encoder on the spindle. Stepper motor on the rotary table. Electronics divider between the two as per John Stevensons horizontal mill used to cut gears. Set the downfeed at a suitable rate and make sure your maths is right in the divider!

Encoder on the spindle is irrelevant because the synchronization is between the rotation of the rotary table and the downfeed.

[ngwanhoe]

Ha. its all boiled down to electronic control or motorise z axis and rotary table. Oh well, I think its better to buy a lathe.

Thanks guys or gals.

[fizzissist]

Simple.

No sophisticated electronics needed, just some good ole' American ingenuity.

Assuming a plain old vertical knee mill....

Mount a flat plate on an angle plate (vertically) equal in length to the dia x pi, and in width to the length of the part at an angle equal to the angle of the thread pitch....picture cutting a threaded tube along its axis and unrolling it flat. That's what you're going to make.

Using a single point milling cutter ground to the thread form, mill slots along the part at intervals equal to the thread pitch. You'll probably need to make multiple passes.

Unmount the part, form it around a mandrel till it's round and the proper diameter. Weld the seam, and finish file the joint.

Use the same process for the female part, and when done, use lapping compound to work them together so that they fit and match.

(before some of you laugh....I've essentially done this once...just to see if it could be done. It can.)

There are older mills out there that have dividing heads that are driven by the table, so you can coordinate the linear motion with the rotary, allowing you to make cams, gears, or as here..threads. Used to have one, a Cincinnati #3. Big, old, ugly, cumbersome. But it worked.

[ngwanhoe]

Simple.

No sophisticated electronics needed, just some good ole' American ingenuity.

Assuming a plain old vertical knee mill....

Mount a flat plate on an angle plate (vertically) equal in length to the dia x pi, and in width to the length of the part at an angle equal to the angle of the thread pitch....picture cutting a threaded tube along its axis and unrolling it flat. That's what you're going to make.

Using a single point milling cutter ground to the thread form, mill slots along the part at intervals equal to the thread pitch. You'll probably need to make multiple passes.

Unmount the part, form it around a mandrel till it's round and the proper diameter. Weld the seam, and finish file the joint.

Use the same process for the female part, and when done, use lapping compound to work them together so that they fit and match.

(before some of you laugh....I've essentially done this once...just to see if it could be done. It can.)

There are older mills out there that have dividing heads that are driven by the table, so you can coordinate the linear motion with the rotary, allowing you to make cams, gears, or as here..threads. Used to have one, a Cincinnati #3. Big, old, ugly, cumbersome. But it worked.

Wow, master

you are too deep for beginer like me. Its hard to imagine / picture what you mean. Do you have pictures or some drawing that can enlighten me?

Thanks

[ngwanhoe]

By the way, my machine is similar to this
Mini Mill - Great Deals on Mini Mills at Harbor Freight

and I have this rotary table
http://ep.yimg.com/ca/I/yhst-6116351...0_2145_1797256

and have this chuck
http://ep.yimg.com/ca/I/yhst-6116351...0_2152_1088670

[fizzissist]

With that mill? Sorry, but you're going to have to get far more creative than I can imagine..or build a setup to drive the rotary table from one of the axis drives, and be able to vary the revolutions/unit of motion of the table.

Be easier, and cheaper, ultimately, to just get a lathe and learn how to single point threads.

You're pushing the limits milling threads on that machine, manually...while this would be a piece of cake for a CNC mill.

[RICHARD ZASTROW]

REAL Milling machines (Kearney & Trecker, Cincinnati, Parker, Fritz Werner etc.) are not popular in this day of CNC Machining Centers. Too bad.

Those of us who actually came before NC/CNC/PC's actually had to devise tooling and whatever it took to produce a workpiece.

A well equipped old style real milling machine can produce damn near anything that fits on the table and sometimes more.

A real universal horizontal mill equipped with a low lead attachment and either a dividing head or a rotary table would have no trouble threading anything it could swing. A vertical real mill could as well but would be a little troublesome adjusting the tool to the lead angle of the workpiece thread.

This is all documented in one of my required apprenticeship text books "A Treatise On Milling And Milling Machines" by the Cincinnati Milling Machine Co. (before they became MILACRON. My copy is a third printing dated 1951 LOL

An example of thread milling is on page 484 of this 910 page text.

Ah, the good old days.

Dick Z