[bogus105]

hi, i will be a happy owner of zay7045 in next few days. My zay is 8 years old... i have a question on z axis. Is it better to controll quill only or whole head setup with stepper/servo? i'm asking also about backlash on quill and z axis dovetail? is there gib key in head assembly to reduce backlash on dovetail?? i saw only two locks on side to tighten head to the dovetail. If there are no gib in a dovetail how does it work when cnc??

[BobWarfield]

bogus, you're much better off motorizing the Z and just locking the quill tight in its uppermost position. You want the much greater travels of the Z and it'll be more rigid that way as well.

Your ZAY is just another RF-45. Lots of conversions around for you to look at to see how it was done.

RE the gib, look underneath. There is a bolt to tighten the tapered gib for Z.

They work great for CNC.

Best,

BW

[bogus105]

thx Bob for reply,
i didn't know that z axis gib is tapered. i have zay operator manual with all parts drawings inside but these drawings are far from perfect... and i haven't seen any detailed pics on web so far. Has anyone have a good source of zay-like mill photos? (sorry for any bugs - english is not my native language...)

[pete from TN]

There are a bunch of photos of My Lathemaster milling machine conversion and tear down/rebuild on my thread " Finally getting started" in this benchtop forum. It is slightly different to the ones sold now but should give you an idea what you are looking at... peace

[bogus105]

i think the differences will be in colour sheme only as my mill was purchased 8 year ago so is as old as yours
i'll check your gallery tommorow
thx!

[pete from TN]

It would be nice to see another ZAY like mine as most are not. Make sure you post pics when you can.... peace

[arizonavideo]

There are a bunch of photos of My Lathemaster milling machine conversion and tear down/rebuild on my thread " Finally getting started" in this benchtop forum. It is slightly different to the ones sold now but should give you an idea what you are looking at... peace

ZAY makes the Lathemaster RF-45 and the IH mills.

They should be almost exactly the same except for upgrades like the two bolt adjustment on the gib strips on the newer machines.

[pete from TN]

If you look very closely at the pics of my machine especially the millhead and the Lathemaster Zay machine that Bob is selling now it will become pretty clear it is not the same machine at all. Even the base casting is vastly different. The machine from Grizzly is more like the Lathemaster in the millhead config. If you look at them closely you will easily see the differences. If this fellow's machine is an older model like mine it would be cool because I would love to see another one like it... peace

Pete

[bogus105]

hi,
now i joined the club My ZAY has serial number 0006! Mill is not fully assembled yet but i'm working on it. I'm gonna power the motor with VFD as i don't have a 3 phase power supply in home. All the stuffs on pic were attached to mill (except machine vise). I paid for all this USD1850. I think it was worth. Drill press, Turn table (250mm dia) are unused same as mill is. I found that controlling Z axis by moving whole head assembly will be pretty hard due to it's weight. is it really bad idea to controll quill only?

[pete from TN]

Congrats on a nice looking machine. With a little cleanup you should be good to go. I think you got a decent deal on the machine with the tooling and the rotab. The mill is basically around $1600.00 and a rotary table like that is around $180-200 so you got a bunch of tooling for free and did not have to pay to ship the machine and stuff so I would say you got a decent deal. As far as powering the quill rather than the millhead, I would say you can do what you want but now that my machine is running and the whole millhead goes up and down I would not have it any other way. There have been others that also say they had problems with the quill travel loosing accuracy. Of course the more you extend it the less rigid it is so you can have deflection a little more. Of course the millhead is pretty heavy but it is totally doable and probably easier overall to do than powering the quill as well. Use a 3/4 or 1" ballscrew and get yourself a powerful servo motor for the Z axis and you should not have any problems. If you do you can always make a counterweight that runs with cabling or a chain from over the top of the column such as many of the larger VMC machines use. Some guys use a gas spring cylinder instead of a counterweight. I do not have one on my machine and it is working well, I have seen rapids of the whole millhead in the 150 IPM range without drama. I may actually reconsider this in a little while and add some sort of counterweight as I think it may make some more rapid speed easier on the motor and the ballscrew because I am hoping to get into some 3D machining down the road that will require some fast accurate Z movement. Incidentally, I removed the whole quill drive assembly and it's cast iron mount and also converted my machine to a belt drive which significantly reduced the weight. I did run it for a short while stock tho so it is doable. I would seriously think about doing the column instead of the quill because it is just awesome to have the machine move to a toolchange position up and away from the work and be able to easily change tools when you need to. The machine without the quill is much more rigid since the spindle is fixed inside the head and nice and tight.

That rotary table would make a nice fourth axis down the road too someday. When you get a chance take a look at my thread and you may see some ideas you can use for your conversion. I HIGHLY recommend doing the one shot oiler setup. It takes a little time but it is VERY worth it with CNC.... Good luck and be sure to post a build thread when you get there.... peace

[arizonavideo]

I would run the quill about half way down and check the slop.

My IH mill, which is made by ZAY, has .006" slop at the spindle with the quill down about 3" unlocked.

My RF-31 has only about .001" It is a much better quill but the rest of the mill is not as strong.

You can use a stepper and a small 251 Gecko drive to run the quill if you wish to save some money but in the long run you will want to do the column.

I just got my Z under computer control and it is not that hard. Got a 1" NOOK ballscrew for $25.00! It had 17" of travel and I had to add a few inches so I got to turn the hard screw down and drill and pin it.

What fun...

It would have been better if the column ways did not have a .003 tight spot in them.

[SCzEngrgGroup]

"My IH mill, which is made by ZAY, has .006" slop at the spindle with the quill down about 3" unlocked." - Yikes! That is awful! Have you complained to IH about that? I can't imagine that they'd be satisfied with that.

Regards,
Ray L.

[arizonavideo]

"My IH mill, which is made by ZAY, has .006" slop at the spindle with the quill down about 3" unlocked." - Yikes! That is awful! Have you complained to IH about that? I can't imagine that they'd be satisfied with that.

Regards,
Ray L.

The quill is not nearly as bad as the column. I had to loosen the gibb strip 6 turns to get the slide to work smoothly. I contact IH and they sent me some lapping compound. I got most of the tight spot out but it will chatter unless I run the gibb out by about 2 turns.

I may have to have the column re-ground for $500 or try to get a replacement from IH.

I have called them three times and they quit returning my calls.

So I guess they are OK with that.

I may start a thread someday in the IH forum with lots of video but before I say too much I am going to give them another chance or two.

I really did not plan on working on the machine for months.

Sorry for the OT. Done.

[bogus105]

Well, i'm not surprised with this 0.006'' free play as IH,ZAy etc. are just chinese cheap machines...Last yeat i recieved an e-mail from china factory in Shenzen where these mill are manofactured and they propouse me such a mill for about $900 FOB or about $960 CIF Gdynia in Europe when taking a 40'' foot container So someone ears about $600 a piece when selling this mill for $1600. We can't be purprised by the fact that these machine are far from ideal compare wit i.e. Bridgeport mills...

Anyway, Arizonavideo where did you get a ballscrews for $25???? here in Europe i can't find ballscrews for reasonable prices as for hobbyst:/ Has anyone some ballscrews for sell?

Also i'm looking for used servos for my mill. I'm planning to use UHU servo controllers (from Germany) because they are cheap. I e-mailed Uli Hubert and already programmed chip costs 10 euros. I already have PCBs and one completed UHU drive.
If someone of you fellas have an info on servos or ballscrews, pls let me know

thx!

[Crevice Reamer]

Hi folks!
I'm very new here, but have spent the last few months reading the forums and doing some research on a CNC mill. The general advice on machines was bigger is better, so I jumped on a deal for a ZAY7045. The machine is set up in the shop and has made some manual chips, but now it is time to make the machine sing. The G540 driver seems like a fantastic bargain, but I am wondering if it is too small for this mill? I don't need super fast rapids, so 1200 oz-in steppers seem overkill. I am mainly making small aluminum parts right now that have less than a 4" x 4" x 2" envelope.

In your experience, what size stepper motors do I really need?
It seems that any motor over 480 oz-in would be fine with reasonable travel speed.

homeshopcnc.com sells a RS23-570 @ 570oz-in that seems like it would work with the G540 (inductance is right, but it can take more current than a G540 can provide) = lower torque if only driven with 3.5A?

kelinginc.net has a KL23H2100-30-4BM @ 495oz-in, but the inductance is ~7mH which is more than the specs for G540

Are there any other steppers out there that would match up better?

Budget for the electronics (3 motors, drivers, BOB) is <$800 and simple is better. Am I asking too much out of the G540? Should I step up to G203s and NEMA 34 motors?

Thanks for your help!
-Chris

The $99 Keling 906 oz. 58V KL34H295-43-8A is a good N34 match for the G540. Wired Bipolar Parallel, it detunes to 520 oz @ 3.5A and if you gear it down 1.23 to one with pulleys it will produce 640 oz at driven shaft. I don't know if this is enough for Zay head, but this combo has been proven to produce 180 IPM rapids on X3 head.

http://kelinginc.net/NEMA34Motor.html

CR.

[arizonavideo]

I don't see anyway 640oz stepper with the G540 will lift the head.

It's not just the 250LB but there is a lot of drag on the slide too.

For any kind of accurate work you want to run the gibb fairly tight which will make lots of drag but even if you can get the head to lift the acceleration will be real bad.

Buy one servo driver for the Z and you might try steppers for the table.

I have a new Gecko servo driver and an extra used servo and pulliy for the Z if you can't find a deal anywhere. I could pre test the setup for you and put it in a box.

I got my ballscrew on eBay, I just got lucky, bad picture and the " I think is is a ballscrew" sales pitch. The nut does have backlash but that is not really a problem unless the head sticks.

[BobWarfield]

If everything is properly lapped, adjusted, and lubricated, the head should move just fine on 640 oz in.

Consider that the stock IH servos are only about 500 oz in.

Further consider that you don't need the Z-axis to be a 150 IPM speed demon. Fine for X and Y, but Z can move at half that speed and be very happy.

Lastly consider that Tormach is a 65 IPM machine.

Just go forward with it. If you're unhappy with the performance, you can always by a single Gecko drive and bigger servo or stepper later. You could also
counterweight the head and radically improve performance that way too.

Best,

BW

PS I haven't seen anything remotely like 0.006" slop in my quill. It needs to be locked anyway while cutting, and once the head is motorized, it may as well just stay locked.

[SCzEngrgGroup]

I don't see anyway 640oz stepper with the G540 will lift the head.

It's not just the 250LB but there is a lot of drag on the slide too.

For any kind of accurate work you want to run the gibb fairly tight which will make lots of drag but even if you can get the head to lift the acceleration will be real bad.

Buy one servo driver for the Z and you might try steppers for the table.

I have a new Gecko servo driver and an extra used servo and pulliy for the Z if you can't find a deal anywhere. I could pre test the setup for you and put it in a box.

I got my ballscrew on eBay, I just got lucky, bad picture and the " I think is is a ballscrew" sales pitch. The nut does have backlash but that is not really a problem unless the head sticks.

You NEVER want to run gibs tight enough to cause drag. If you do, you will induce backlash, due to "stiction". If it's necessary to run the gibs that tight to get accurate movement, then you need to lap your ways. When the ways are in good shape, the gibs should be only tight enough to take *almost* all of the slop out of the movement, and the axis should still move very freely. On my knee mill, I can disconnect the ballscrew and push the 49" table end to end fairly easily.

I move the 500+ pound knee of my mill with an 850 oz-in peak/140 oz-in continuous servo motor, and it'll do 75 IPM. A 640 oz-in stepper should be plenty for an RF-45.

Regards,
Ray L.

[BobWarfield]

You NEVER want to run gibs tight enough to cause drag. If you do, you will induce backlash, due to "stiction". If it's necessary to run the gibs that tight to get accurate movement, then you need to lap your ways. When the ways are in good shape, the gibs should be only tight enough to take *almost* all of the slop out of the movement, and the axis should still move very freely. On my knee mill, I can disconnect the ballscrew and push the 49" table end to end fairly easily.

I move the 500+ pound knee of my mill with an 850 oz-in peak/140 oz-in continuous servo motor, and it'll do 75 IPM. A 640 oz-in stepper should be plenty for an RF-45.

Regards,
Ray L.

Matters of degree there. You want them as tight as they can be without causing the backlash. In fact, tightening until measured backlash starts to bump up and then backing off a tad is one way to adjust the gibs.

It turns out, that if you lap the ways and run a one shot oiler, you can run them pretty darned tight without adding any backlash. This is beneficial to rigidity.

I run mine tighter than X or Y, for example. I can move X or Y by hand pretty easily, but not Z. The cantilevering of the head is partially responsible.

If I don't remember to pump the one shot after the mill has sat for a while, I can almost guarantee a servo fault on Z at some point in a CNC job, particularly if it is a small move (sure sign of stiction!).

All this has made me a huge believer in having a one shot, BTW. Let's me run the machine a lot tighter.

Cheers,

BW

[bogus105]

you were really lucky Arizonavideo, pls check if your set manage with Z head and pls tell me how much you want for it? i'll check then if i have enough money to purchase such a thing or have to wait and collect more funds...

have you fellas consider counterwieght in the back of the column to make life easier for the Z motor? i know that this solution will increase head assembly inertia but it also decrease stresses on leading screw/nut/bearings and decrease motor Nm requirement

and one more thing: where can i get one shot oiler? how much is it? is there any thred on how to do one shot oiled mod of the mill (rich with photos)??