1st milling with the ZAY7045 Milling machine-Question

Ok, at moment I am busy milling the 2x small tools I made to bolt and fine adjust the swivel bed 100% square. I grinded them with grinder , drill holes and tread on on each, and mill the bases flat so they bolt on square to bed base.

I set up the cutter by letting the 4x brazed inserts tips down on a round plate on top of vice I considered flat enough, and tightened them with least stickout, just a bit.

Today I mill their top sides to same height and sqare to the base.

My question is, is this type of milling consider a good or bad practice(-?) seeing its an interrupted cut, from what I can it is somewhat convrntional milling with the centre of the facemill lined up with the centre of the part and milling it from front view left to right under through cutter with cutter spinning clockwise. The cut result looks perfect to me, no irregularities on face.

Facemill(Received with mill)=80mm MT4 with 4 clamed brazed carbide inserts.
With of part=20mm...................Cut with 80mm facemill.
Lenght of part=50mm..Clamed in vice.
Speed=II + L setting=540rpm.

Good or bad-?
If ok what depth of cut maximum you suggest for this operation, speed suggestion 80mm versus 20mm-?

Some general comments:

I don't use an 80mm diameter cutter on my Bridgeport, it simply doesn't have the power or rigidity to make proper use of it

An 80mm cutter is really too large for a part that is only 20mm wide. The cutter needs to be offset from the work centre so it is cutting on one side, or the other. If the cutter is central with the work then the cutting edges are being shock loaded each time they enter the cut.

The feedrates seem very slow, for a 4 edge cutter at 540rpm I'd be feeding at 200mm/min or more

For facemilling I normally use a 1mm depth of cut on the Bridgeport and up to 5mm on the horizontal, but it depends how much power is available. My Bridgeport is only 1.5hp, whereas the horizontal is 5hp.

Andrew

Thanks, you have a point about the offset thing. I started the other day with accidently had it off set towards me(The front), and it sounded better than today, thats why I decided to question it.

My feed rate was slow manually, slower than the other day with offset due to sound. I think I might have cut 1-1.5 mm off in this go.

I cut one, the cut looks 100% well to me. I will change the offset to the other day, and cut the 2nd one that day.
-I will then remove facemill and inspect cutter tips.
-I will then call it a day on milling till I got the right ER32 or ER40 tools & cutters.

Edited By Chris Mate on 18/01/2022 11:44:52

On the other hand I use an 80mm insert cutter quite a lot on my weedy little benchtop mill. Where at one time I might have put a flycutter in to face the top of a block of aluminium or other non ferrous metal now I use an 80mm six insert cutter (inserts for aluminium) and get the job done in about 1/20 of time. Its as happy on a bit of 20mm wide material as it is on 75mm wide and I don't bother offsetting it.

For steel and iron have a 63mm one set up with general purpose inserts which cuts OK if you keep to a light DOC (0.5-1.0mm) and light chip load. I do offset this one to try and keep at least one insert cutting at any one time

JasonB, I was cutting steel, I am going to go to the other extreme of off -setting it more than the 1st time, and listen to the sound and compare cut surfaces. The mill never sound it would struggle, its just the sound of the interrupted cut I noticed was different..

Note:Coolant and costs....This effort is just a personal choice which I hope works out good without having a CNC like enclosure.
The reason I have not bougt ER collets & cutters yet, Is I am spending money on stainless steel trays & guards with the purpose of catching chips, route flow coolant and be easily cleaned and removable, so for the vice I have a different setup than for just the table.
I watch milling for 2 years now, and in this regard I have an idea of how I would like to do it to minimilise the mess coolant can make, I am finished with tha tank, pump, filtering and pype routings back to the mill with nozels(3x) flow controlable with backflow from back from pump back to tank. The catch areas and those routing back to tank I must still do.

Edited By Chris Mate on 18/01/2022 12:58:40

Ok, so I offset it quite a bit towards me(Y+...-? from the centre, and the sound if much different softer, and I get the feeling I can feed it faster if I want to.

I don't have DRO, so I interswopped them in vice(twice) till both down to 17.5mm.
The finish is good and evenI would say, very happy with that.

Will inspect the cutter tips tomorrow.

So thanks for information given, this was an interesting experience about cutting sound.

For what it's worth, the flood cooling system I bought for my mill wasn't a good investment because I so rarely switch it on. With hindsight, I'd buy ER32, cutters and almost anything else before fitting flood cooling.  My DRO is far more useful.

One reason is the mess: although most of the coolant goes back into the tank, cleaning up adds several minutes to each session and produces nasty wet swarf.

Another is the relatively slow, light type of mixed size work I do - I guess a bit under half the metal I mill is steel, and normally only moderate amounts of it are removed per session. Having to readjust the nozzle's aim when doing mixed work is a time-waster. For moderate removal rates, it's enough to apply coolant and remove swarf with a brush. For roughing out steel, I mostly dry cut with carbide. Only rarely do I remove lots of metal with HSS cutters, which do benefit from flood cooling, especially when the jet is powerful enough to blow swarf clean away from the cutter. (Avoids mincing.)

Your mill is a notch bigger than mine, and flood cooling won't be wasted if your workshop specialises in cutting long stretches of steel quickly. Can you report back in a few months? Be interesting to know how useful you find flood cooling in practice. I don't think I'm the only one to find flooding more bother than it's worth.

Dave

Edited By SillyOldDuffer on 18/01/2022 16:06:54

The only machine I regularly use flood coolant on is the Surface Grinder.
On that it’s mostly about keeping the part at an even temperature and attempting to control the fine abrasive dust - by making it wet and heavy.

I do use flood occasionally on the lathe (CVA) but more often after a cut to cool the part for measurements rather than during - the spray tends to make a mess.

My mill (TOS FNK25) hasn’t had coolant in the sump since I bought it over a decade ago.
Most cuts are dry, tapping or drilling I might use a little oil from a can but it has power and rigidity to push carbide through most things when milling.

I’m going to add coolant to the little CNC, because unattended cutting of alloy has a tendency to weld onto the cutter and flood or air blast moves the chips away so should help with that. The CNC is built into an enclosure, so spreading mess isn’t a problem.

Dave

Hi Dave, I have just millied without coolant just a spaycan cutting fluid, so thats no problem.

I could have bought other similar mill without coolant tank option, but none of them had the swivel bed. The company I bought this from refused to sell it without the coolant or cabinet. So seeing I paid for it, I decided to give it a try, and in the process I want to experiment with my own version of an oil catch can floating in the tank, keeping oil from above from entering the coolant mix, it will push over in a little container by itself/levels.

The mist I rules out seeing I don't want to breathe that, same with the smoke, the lathe is less of a problem where its located.

I will probably use only a small slow stream, the rest circulate filtered back to the tank. I can also add a residual small tank, so if a small job, I dont start pump.. On advice I will mix the coolant a bit more oil.
-This is just a personal choice, if it does not work out as I thought, not the end .

Edited By Chris Mate on 18/01/2022 17:32:04

Although my lathe has got a flood coolant system on it I generally use a squirty bottle when needed as the flood makes far tooo much mess. Same on the mills unless using a big face cutter then I use mist coolant. I got fed up with wet floor, bench etc with flood coolant. On Ali I use a WD40 squirty bottle.

regards

One advantage of offsetting the cutter to one side, is that you will never be climb milling.

In terms of feed rate, once you have set the speed to give the desired cutting speed, a feed of 0.002" (0.05 mm) per tooth should work quite well. So with a six inset cutter, 0.30 mm per rev.

HTH

Howard

Howard, interesting remark, I was not sure about climb milling with the facemill, if I put it on centre, ok the time of the cut is shorter, the angle is more headon, the sound if I can describe it was blunt and it sound like its putting play on mill gears in gearbox or bring out the play and it looks like it pushes the cut like a bulldoser, compared to a grader with blade sideways scraping the road, ..while off centre it's more silent and free cutting sounds good, however I could not see a diffrence in quality of either cuts apart from the angles finished.

Edited By Chris Mate on 19/01/2022 03:05:05

Ok, I could not stop thinking about this and after some time my mind came to a resting point somewhere.
I made a simple sketch in paint and uploaded it, illustrating my current view on this triggered by what other mentioned....

Today I am going to bolt the 2x parts together seeing they have holes, and mill both small ends together clamped in vice.

Some questions going through my mind:
0-Spindle Speed=+/-500rpm......The time a cutter tooth spends on the part.
1-Face Mill size=80mm
2-Face mill teeth=4....wide spacings..
3-The part with=20mm......
4a-The -amount of teeth- versus the part with and the -gaps or not- in play.....
4b-The mill has a gearbox or not....
5-The spindle Rotation=Clockwise.

6a-The part offset towards me...Angle into work and out...Grader

6b-The part centred to spindle centre.=Blunt cutting...Bull Doser

6c-The part offset away from me...Angle into work and out...Grader

It seems one can have "Conventional Milling" ....."Blunt Milling"..... and "Climb Milling" like but not similar to other side milling practices.


 

Edited By Chris Mate on 19/01/2022 06:06:45

I'm not sure why offsetting the cutter means you will never climb cut, surely that is all down to what direction you feed from or as in your last option the side the cutter is offset to. If you inadvertantly feed in a climb direction the offset will make it worse than if the cutter were centered

The last of your options would be the most likely to see the cutter self feeding into the work depending on DOC and backlash in the machine so take care.

The other option on your 20x60 faces to get as much contact as possible is to feed in Y rather than X

I did these couple of sketches some time ago for another thread but it shows that with the tool central to the work you don't always have an insert engaged which will cause a gearboxed head mill to make noise. I think this was for a 50mm dia cutter

But if you off set there will always be at least one insert engaged so the gearbox stays loaded and runs quieter, the less steep entry angle also helps soften the cut.

You will tend to get a bit more noise at the start and finish of the cut as engagement is less as the insert just swings across the narrow corners So on smaller work where there won't be a long cut in the fully engaged situation it does not always pay off to offset the cutter. So if your ends are 20x20 then they are better cut with the spindle central..

Makes sense Chris.

A mill with a swivel bed is outside my experience: didn't even know they existed until you arrived on the forum! Interesting features: a big machine of that style, powerful motor, built-in cooling, and a swivel bed. As the machine's probably new to others, be good if you would post every so often how you're getting on with it. User reviews are always fascinating and helpful.

Cheers,

Dave

Traditionally a universal mill was a horizontal with a swivelling table to allow items such as helical gears to be cut, like this:

I'm not sure what feature Chris is referring to as a swivelling bed?

Andrew

Really annoying, I can't find the picture of the ZAY7045 showing the swivel, but it appeared to be a simpler version of this machine:

Or have I got it wrong again?

Dave

Disclaimer:I got a bit confused if I google the axis explanations, so correct me if I am wrong.
-I assume the X-axis is the one with the 1-Handwheel and you crank it towards or away from you.
-I assume the Y-Axis is travelling left to right in front of you with the two handwheels, one on each side.
-I assume your Head with gearbox going up and down is your Z1-Axis, and your quil up and down your Z2 axis.
- Will post a picture from the manual and mark the parts we talking about.........

Sorry if I used incorrect wording:
1-You have the lower cabinet on which it mounts.
2-Then you bave the power base which bolts to the cabinet.
3-The X-Axis are from the lower base top.
4-Then you have a center piece which make the swivel possible. This centre piece has a lower part which form the X-axis and its front handle. The top part houses the Y-axis lower part and you lock it down with two large bolts, one on each side.
5-The Y-Axis part of the table mounts and slides on this, controlled with the two handles, one on each side.
6-The Y-Axis is the one that swivel 45 degrees through 0-Degrees to 45 the other direction.

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.
-So I assume if you have a mill without the swivel bed, and you get your vice dialed in 100% you have an accurate mill in that regard.

Added pictured explanation of how it swivel:
The Mill I bought was named=ZX45 as plate shows on face of it.
However the manual I received with it say its ZAY7045M, where M=Indicate the swivel function option.
It is sort of heave, If I hoist it without cabinet, my new 2-Ton engine hoise dont move by pushing it, I had to lever it with a jack handle along the floor. I am not sure exactly what it weighs, seeing themanual in places not accurate, like it has a MT3 spindle, no, it has an MT4 spindle. It looks similar to some heavier duty drill presses.
It has a 10A motor 220V. It seems not sloppy in the axises.

Note-2:
I did a few electrical mods to the machine.
1-The thread cutting feature, the upper limit switch was garbage. I removed it, and fitted a quality switch inside towards the bottom, but it now always indicate the quill in its top resting position.
2-I added a 24V fuse and on/off switch.
3-I must still add a safety off switch to a foot pedal as I did with the lathe if both hands are occupied to switch it off..(After the carnage happenned if it fast).
4-I did various mods to the coolant system, still busy with the returm path from bed.

Edited By Chris Mate on 19/01/2022 13:48:44

Edited By Chris Mate on 19/01/2022 14:01:30

X is the side to side movement along the table

Y is front to back

X is up and down