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Black Forest
09-11-2011, 04:30 AM
What operations would one use a swivel table on a mill? The table swivels on the XY plane. It does not tilt.

My mill has such a table but I can not think of when one would use that function.

I asked this question in the "shameless gloat" thread but thought maybe more people might see it in its own thread!

DATo
09-11-2011, 05:39 AM
This is usually used for cutting helical gears. The machine type is called a 'universal milling machine'.

http://www.youtube.com/watch?v=tePh773MxNA

Note that the mill table in the video is set to an angle.

Edit: That's what the graduations around the body of a Bridgeport are for. Instead of tilting the table you tilt the entire ram. In this Bridgeport scenario you'd use a 90 degree attachment on the spindle and an overarm support on the dovetail of the ram to convert the machine to a horizontal mill. The workpiece would remain centered on the X axis and the entire top of the machine is rotated to the proper angle.

Sir John is right. Substitute "rotate" for "tilt" in the above. We Colonials are known for mutilating the Queen's English.

mike4
09-11-2011, 05:44 AM
I have used this feature on mine to cut several wedges for a machine , using the horizontal spindle and slitting saws.
I simply clamped a piece of 4x1 HRS to a sacrificial aluminium plate and swung the table to where 1 cut would result in two finished wedges .
Admittedly I was only cutting about 450mm long parts , but when theres ten required it was the easiest way that I could think of as I didnt have access to a plasma cutter which could cut 25mm .

I have toyed with the idea of a keyway in a tapered shaft,but dont have the time to play , this setup would use the vertical spindle with a cutter designed to cut the keyway in about five passes , something akin to a "t" slot cutter.

One of the local quarries has a small crusher which uses a 300mm taper to lock the main drive to a pulley .

Michael

SGW
09-11-2011, 07:03 AM
For cutting flutes in a tapered reamer, among other things.

willmac
09-11-2011, 07:34 AM
< Pedantic mode on>

It depends what type of swivel table you have. If the whole table and its axis, leadscrew/drive swivel then you have a true universal milling machine and this can be used for milling helical gears and other complex parts. However not all swiveling tables are like this. The table on my table swivels, but the X axis doesn't. See picture:

http://i122.photobucket.com/albums/o248/moorbrook1860/Thiel15901200dpi.jpg

This means that although it is extremely versatile it is not correctly a universal mill and can't be used to cut helical gears in the same way - (although it can with other accessories). The other applications mentioned such as keyways in tapered shafts, wedges etc are easy with this type of table. It can also be used for compound angles and lots of really complex setups because the table has tilt, tilt, swivel and slide. But all of that still does not make it a true universal mill.

Boucher
09-11-2011, 08:11 AM
I have a 6 Yuasa Tilting table with a small 3 Jaw chuck. The indexing feature is handy for drilling hole patterns as shown here.

http://i109.photobucket.com/albums/n50/boucherbyron/IMG_0237Small.jpg

The whole thing only weighs about 25 lbs. And occupies a small space on the table. I find it much more useful for the type work that I do than the big 10 Rotary table.

John Stevenson
09-11-2011, 08:11 AM
< Pedantic mode on>

It depends what type of swivel table you have.



Clearly states:-

The table swivels on the XY plane. It does not tilt.

< Pedantic mode off> ;)

Black Forest
09-11-2011, 08:59 AM
On my mill the ball screws swivel with the table.

So I guess I have a true Universal mill. I don't care if it is or not. I just wasn't sure what I would use it for.

Thanks for the replies.

willmac
09-11-2011, 10:02 AM
John -

Not sure what point you are making here. I didn't claim that his table did tilt. Its all about whether swivel table = universal mill. I don't think it does.

willmac
09-11-2011, 10:38 AM
Black Forest -

"So I guess I have a true Universal mill" - Yes - and that means that you are able to do the things that DATo describes and shows in the video. I can't (directly) with my mill because although my table swivels the axis doesn't.

Arthur.Marks
09-11-2011, 03:36 PM
Why collecting manuals for machines you don't own is worth it...
Why spending money on old, "outdated" books pays off in the long run...

I sometimes worry my generation has lost a lot of practical set-up knowledge from the manual machining era. Here is one example--helical milling. I struggled with the "true universal" designation for a long time because I saw it applied in manufacturer literature to machines which seemingly didn't have a "true universal" swivel table. Then I found these, which gave me some needed examples of how to do it! I'll accept that the term "universal table" or even "universal milling machine" is used as a descriptor for certain specific features on a milling machine, but I will not accept that you need a "true universal" mill to cut "true" helical features correctly ;)
http://i771.photobucket.com/albums/xx357/Arrak_Thumrs/Widgets/helices1.jpg
http://i771.photobucket.com/albums/xx357/Arrak_Thumrs/Widgets/helices2.jpg
Even a Bridgeport can do it. Think about it...

willmac
09-11-2011, 05:40 PM
Arthur -
Perhaps being pedantic was a bad start! Yes, a Bridgeport can do it. My mill or any similar Deckel type mill can, but in a different way, and I like the second set up picture that you have provided. I guess the point that I was trying to make (badly) is that 'universal mill' used to have a specific meaning - a horizontal mill with a full swiveling table. A lot of the old books show such a mill doing helical milling and cutting helical gears. Even hobbing - John Stevenson has a nice electronic setup on his universal mill for this specific job. I guess it depends what value the definition has and whether it matters depends on what you want to do.

uncle pete
09-11-2011, 09:13 PM
Having a universal mill or lets say one where the main table pivots horizontaly is only one part. To do helical milling I'm sure most have grasped that a universal dividing head geared to the X axis leadscrew is a requirement. Vertex still make them and quality wise their............ ok. Finding one on Ebay that's OEM equipment for some of that really nice and pricey Euopean equipment? Good luck and bring a boat load of cash unless your really lucky. I have seen a few for sale in the U.K. for not too bad of a price tho.

Pete

darryl
09-11-2011, 10:07 PM
Swivelling in the x-y plane- will it do a 360? If so, you can set the pivot axis offset by a measured amount from the mill spindle axis, then do any operation where you need to mill a circular arc, or the whole circle. You can do blind circular grooves, or sections of a circle in grooves. A rotary table might be better for this, but it probably won't handle as large a diameter of workpiece. Being able to crank the table around its pivot point- well that would make it a rotary table of sorts. I do lots of milling- I call it pivot point milling- where I control the rotation of the workpiece by hand. I set start and stop points for where I want the cutting to begin and end, and I make sure that one of these points is keeping the work from rotating due to the cutting action. In other words, this is the point where I start from. If I'm rounding the end of a connecting rod of some kind, this is usually how I do it. It works pretty good for small things, and it works pretty good for milling the outside edge of large discs to make it round and concentric with the center hole.

Having said all that, the swivelling action has to be tight. If it's sloppy, forget all of the above. It only works well if it's free to turn, but has no play.

drof34
09-11-2011, 11:21 PM
Swiveling the table is not about the orientation of the table but about the path of travel the table takes. For example, if you have a universal horizontal mill, swing the table around to any angle( even 45*)and place an indicator mounted on the column so that it reads on a vertical edge of the table. The indicator will stay on 0 as the table moves to and fro( with the exception of scars).

This also means that you cannot cut an angle on something by just pivoting the table to that angle.

In post #2 Utube video, the cutting a helical gear with an involute cutter, the DH is being driven by the table imparting a twisting action to the work and with the table swiveled to the proper angle, the center of the cutter remains over the center of the blank, otherwise it would just cut from one side to the other and only be deep enough where it crossed the C/l of the blank.

This is with an overhead cutter. When the cutter is placed at a horizontal center of the work such as a vertical mill, its a different story.:confused:

willmac
09-12-2011, 07:34 AM
Swiveling tables (XY plane) are very useful, but in most cases they can't take the place of a rotary table. Typically the swiveling table has no means of controlled rotation in a cut. It is intended for angular positioning often by hand, but sometimes with the assistance of a worm drive. The rotation is usually restricted - no full circles. Some high end Deckel tables do have the ability to be used like a rotary table however.