1st milling with the ZAY7045 Milling machine-Question

[Chris MateParticipant @chrismate31303]

JasonB, thanks man, I appreciate this and will stick to this then..

Both manuals for the Lathe and Mill is pretty useless and poor print quality you get with it.

Just a question further about Z-Axis.

If you want to get a 4x axis DRO:
Is it correct to call the Mill Head moving up/down=Z1
And Quil moving up/down=Z2

[JasonBModerator @jasonb]

I'm assuming by 4th axis you really mean one with 4 straight scales in which case you would be better off getting a console capable of "summing" this will give one display for any vertical movement be it from moving the head or the quill so for example if you raise the head to change tooling you can bring it back down to any position and then use the fine feed of the quill to put on the cut.

In milling terms the 4th axis generally refers to a rotating axis like a rotary table

[Nigel McBurney 1Participant @nigelmcburney1]

Universal mills had a swivelling table primarily to produce spiral gears and other work which had helix form,the general practice with these machines which had 3 tee slot tables was for the centre slot to be central to the table pivot and the dividing heads had tenons which aligned the axis of the head/tailstock to the centre of the central tee slot,so anyone contemplating the restoration of a universal mill do not attempt to clean up the central tee slot,leave it alone and if making new dividing head keys make sure edges of the keys are equispaced to the keyway in the base of the head. When finishing work with a cutter which is larger in diameter than than the width of the workpiece place the cutter central to the work, Unless the vertical mill spindle is truly vertical, any cutter be it single tooth or multi tooth will produce a surface which is hollow towards the centre of the cut so it is better to get the any slight hollow in the centre of the workpiece. if any is not convinced by this try setting a cutter with the vertical spindle set over a few degrees the result would be a elliptical groove if the head was set over at 90 degrees it would of course produce a half round slot.

[Chris MateParticipant @chrismate31303]

Thanks JasonB, I found it(dro-linear-encoder-summing-interface) will look into it.

Edited By Chris Mate on 19/01/2022 18:56:28

[JasonBModerator @jasonb]

That's the sort of thing but some of the readouts will have that built in, eg 4 sockets on the back but just 3 rows of display but they are the more expensive ones so worth checking the prices as all in one may still be cheaper than the readout and separate box of tricks

[Chris MateParticipant @chrismate31303]

Correction :
illustration for ZX-45 (ZAY7045M)-Swivel bed Mill
>The "M" indicates the swivel option in the model type.
Note:The X-AXIS swivel around zero degrees mark at split.
To dial in your vice fixed jaw square, …you must 1st line up this X-Axis square to Y-axis, if not 100%, its difficult to get vice set 100% square. I have made 2x adjusting blocks(Bolt-On) with screw adjusters to easily square this bed (X) without tapping with a mallet, it can be easily removed if in way of swivel.
 

Edited By Chris Mate on 19/01/2022 20:04:30

[Anonymous]

Posted by Chris Mate on 19/01/2022 13:27:17:

7-If I want to dial in my vice, I must 1st dial in the Y-Axis swivelled to 0 degrees. I have verified and fine adjusted it using a precission square running the X-Axis forward and backward in relation to spindle. If this is not exactly zero, I found I cannot dial in my vice 100%. I think this may be interesting, seeing if you dont have a swivel bed Y-Axis you rely on its manufactured accuracy, which if slightly out, is a difficult job to get right, so I assume in such a case you can spend hours and just get your vice 97% say accurate as example.

I think your geometric logic is wrong. When you are indicating on a vice jaw, with the indicator on the mill body, you are aligning the vice to the ways of the table, and should be able to get it as close as you wish. What the angle of the table is relative to the theoretical perpendicular X direction is irrelevant.

On my Bridgeport (fixed table) it only takes a minute or two to align the vice to better than a thou in six inches. When setting the vice on the horizontal mill it takes the same. I have normally set the swivel table on the horizontal parallel the ways on the Z-axis first, so that the cutters cut true rather than at an angle.

Having a swivel table does not help in setting the vice accurately.

Andrew

[Chris MateParticipant @chrismate31303]

Andrew, my indicator was in a chuck(Z1/Z2-axis) in the spindle before I fit the face cutter, I then have the spindle in lowest gear and grip with hand to take up play, it then stays there, so the spindle does not move/turn, I then indicate the vice fixed jaw placed on X-axis which can swivel).
As soon as I receive my stainless tray to modify to sit over vice, I have to take it off, and will expiriment again. The indicator was not anywhere on the mill body positioned-Do I understand this wrong-?

Edited By Chris Mate on 20/01/2022 04:29:52

[Chris MateParticipant @chrismate31303]

Request: Can one of the moderators please close this thread, as its now a complete mess and serve no purpose.

I will carry on with the mill as time goes, if I understand something wrong, I will see/measure it in the part and learn from there. Thanks to those that gave inputs.

What I will do now is put a scribe in the spindle/drill chuck, fit a flat piece of aliminium to the vice, make a scribe with the spindle in the surface as it is now squared positioned according to indicator in spindle, then I will play around with the vice, table(x) and combination of both and see how and where the scribed lines go, I wont live long enough to go for an engineering degree, so it down tio the ground for me then.

Edited By Chris Mate on 20/01/2022 05:07:28

Edited By Chris Mate on 20/01/2022 05:08:25

[JasonBModerator @jasonb]

You need to square the table first so it is at right angles to the fixed Y (front back) Best way I can think of is to clamp a good quality square to the table, clock it true to the fixed Y. Then swivel the table until the other blade of the square clocks true in X.

If the vice is set true on a table that is still a bit angled you will make parallelogram parts not square ones.

If you don't follow that I can sketch something.

A magnetic holder for the Dti will be a usefull addition to your tools

[Anonymous]

Posted by Chris Mate on 20/01/2022 04:25:29:

Do I understand this wrong-?

Setting the swivel table parallel to X and aligning the vice are separate issues. The only time I use an indicator in the spindle is when tramming the mill. The spindle may not look like it is moving, but it will be. I'll take some photos this evening to illustrate what I do.

Andrew

[Chris MateParticipant @chrismate31303]

JasonB, that is what I have done.

1-The Y-Axis is fixed and cannot move accept forward and backwards to and from the Z-axis, unless theres a manufactured problem and you need to fix that.
2-I have squared the X-Axis to the Y-Axis with a precission square, I only use for this pupose, I actually going to get a larger one. The X-Axis is part of the top of the swivel bed above the split.
3-Now I use the dial indicator in the spindle   to trim the vice rear jaw to the X-Axis which is square to the Y-Axis.

1 to 3 is exactly as I did it. In other mills the X-axis is fixed square suppose to be to the Y-Axis permanently, so unless theres a manufacturing problem or loose gibs, it must be ok, so you only left with the vice, head, and the X/Y towars the vertical column(shimming).

This is my understanding, except the confusion over the X/Y axis.

—————————————————————————————-

Andrew Johnstone:…"Setting the swivel table parallel to X"…

I am not sure I understand you here, my mill does not have more sections in the bed I can do that……I assume you mean setting the X-Axis=The top section of swivel bed above the split…square to the Y-Axis. Maybe your mill is different regarding the swivel parts its made of-?

Edited By Chris Mate on 20/01/2022 10:54:36

[JasonBModerator @jasonb]

That sounds OK to me, Andrew actually having a mill like that may have a better method.

I just have a small lever type dti on a magnetic base that sticks to the underside of the head and run the fixed vice jaw against that tapping it until I'm happy and then snug down the fixings. If you have a power X feed then it's even easier to just set it slow and tap as you go.

The smaller vice I have a couple of blocks in the groove sunderneath and they locate it reasonably well for most things by just pushing back against the tee slot a sit's tightened 0.01mm over 80mm does me for most things that vice gets used for.

[Chris MateParticipant @chrismate31303]

JasonB: I have certain trust assumptions I make and believe it is true points or surfaces that matters

Trusting points/Surcfaces:
(Till proved incorrectly manufactured or otherwise)

0a-The spindle centre…..I put the dial test-indicator inside the spindle centre and trust that in my case that is more accurate to the operation than any outside surface of the gearbox where they used body putty as filler.

0b-The X-axis hardware metal surfaces:These surfaces top and around looks very neatly grinded. I do not trust this mill's bed 4x grooves to be accurate on the insides, so say for example I put a precission parralel in groove to press a square and the sweep from that, I dont trust this way here.

Step-1:
So I clamp the precission square to the front of the X-axis bed, then position the test-dial indicator from spindle. locked out its backlash with hand so indicator stay put(Lowest gear set), I then swept the other part (90degrees of square) with the dial indicator by cranking the Y-axis. Now to me if this stay zero reading my X-axis is moving square to my Y-axis and at the same time I can claim my swivel bed is lined up at 100% zero mark.

Step-2:I Now assume X-axis is moving square to Y-axis.(Step-1 result)
So now I dial in the vice fixed jaw with dial test-indicator sweeping the fixed jaw by cranking the X-Axis.

Result: I now trust that the fix jaw of my vice move square to the Y-axis as I wanted in this case as I crank the X-Axis…I also trust that if I clam a 1-2-3 block in vice, it will swept zero reading if I crank the Y-Axis.

If I now cut a block square, and its not square……I have a problem to discuss with company I bought it from..

Edited By Chris Mate on 20/01/2022 12:47:13

Edited By Chris Mate on 20/01/2022 12:48:39

[Chris MateParticipant @chrismate31303]

From the manual, poor quality, I illustrae the swivel parts involved:

[Anonymous]

There's no need for me to post pictures as JasonB has already done so.

On the Bridgeport, with a fixed relationship between X & Y, I am only aligning the vice jaw to X-axis movement. The main differences with respect to JBs picture are that I mount the DTI on the Y-axis ways, and indicate the back of the fixed jaw for convenience.

On the horizontal mill I'm doing something different in that I am aligning the swivelling table to be parallel to the Z-axis ways on the column. I'm not aligning the table to the Y-axis. I take it as a gjven that the Y-axis is perpendicular to the Z-axis by design and manufacture. Of course in horizontal mode one is also unlikely to be cutting in X and Y during the same operation.

I'm going to drop out of this thread now.

Andrew

[Martin ConnellyParticipant @martinconnelly55370]

Just for future clarity, rotation in the XY plane is the C axis. The directions for the linear (translation) axes, based on a stationary workpiece and a moving cutter are, X positive is cutter moving left to right, Y positive is cutter moving away from the operator and Z is cutter moving upwards. This is the same as the convention XYZ used in 3D graphs. Rotational axes are A, B, and C and are about X, Y and Z respectively. A right hand lead screw moving in a positive direction in a threaded hole will also be making a positive rotation.

If you have a typical vertical mill then the relative movements are the same but the workpiece will be moving, not the cutter. So a positive X translational movement will move the table right to left under the stationary tool.

The normal cutter direction in a Z axis spindle is a negative C axis rotation. So this machine has an X axis that can make a C axis rotation. If you swivel the X axis so that the right hand end is nearer to the operator then that is a negative C axis rotation.

Martin C

[Chris MateParticipant @chrismate31303]

Martin Connelly, just to let you know, I really appreciate this reply of yours.

In the mean time if you search "Conventional Mill" differences with other vertical mills, theres some interesting knowledge I did not know about……, so this is a Conventional Vertical Mill/Drill I have, they just did not say it like that in sales or manuals from what I got.

Edited By Chris Mate on 21/01/2022 14:57:06

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