[davlovsky]

Hello forum,

I have a Grizzly g0619 milling machine that I would like to convert to a CNC machine, and just wanted to gather a little more information before making any purchases.

The kit I was scoping was this one: http://www.heavymetalcnc.com/portfolio/
Specifically, the X3 w/ premium ball screws. Is this all that's required for hardware?

My main questions are concerning the electronics, specifically the motors. I do low volume, mostly aluminum, and then some plastics as well. Maybe occasionally, I'd do steel with light passes. What kind of torque would I need for machining aluminum with relative ease? Doesn't have to be HSM or anything. No outrageous depths of cut or anything.

I saw people going with ~620oz. in. Nema 23 motors for the x- and y-axes and then a Nema 34 1100oz. in. for the z. Would it be a total overkill to go with ~1000oz. in. Nema 34 for all axes?

That being said, with that aforementioned hardware kit, and the 3-axes CNC kit (motors, drivers, controller, power supplies), is there anything else I would need beside CAD/CAM, computer, machine control software?

Thanks,
davlovsky

[dazp1976]

A couple of small things I'd suggest to eliminate any chances of electrical problems.
Use a separate PC dedicated to just the machine only and use your normal home one for CAD CAM.
GX20 connectors and shielded 18awg cable for xyz to motors.
Shielded cable for pul/dir signals from BOB (20awg is plenty).
Don't use the power from PC to run 12v/5v use separate supplies for isolation.

I know it's well outdated but if planning on using Mach3 and a BOB via parallel port I still say 32bit Winxp sp3 is the best OS imo.

[davlovsky]

dazp,
Thanks for the reply.
Let's say hypothetically, money isn't an issue.
Would you go with Option 1 or Option 2? Why?
I understand that servos (or stepper hybrids) are harder to tune, but the closed-loop system (encoder built-in to the motor) would provide more precision/accuracy, correct?
They're definitely quieter.
I guess I'm looking for reasons not to go with the servos, and just go with the steppers.

Thanks,
davlovsky

[davlovsky]

Also, I will have to replace the spindle? Does anyone have any suggestions regarding a replacement spindle for a G0619 CNC conversion?

[dazp1976]

dazp,
Thanks for the reply.
Let's say hypothetically, money isn't an issue.
Would you go with Option 1 or Option 2? Why?
I understand that servos (or stepper hybrids) are harder to tune, but the closed-loop system (encoder built-in to the motor) would provide more precision/accuracy, correct?
They're definitely quieter.
I guess I'm looking for reasons not to go with the servos, and just go with the steppers.

Thanks,
davlovsky

The guys doing it properly go for closed loop (with servos). Both those systems use steppers but the encoder should have it's advantages for improved accuracy.
I can only really go on what others have done and my (lack of) experience from what I've learned from my starter Seig X2.

I'm on a budget for now and I also looked at the 1232oz/in set for my new machine but I'm not a fan of the 5kg weight.
I think I'm going to go for this 1090oz/in set myself:
?German Ship & No Tax?3Axis Nema34 Stepper Motor 1090oz,100mm, CNC Cut Engraver | eBay
I do already have a 1600oz/in for the Z which is prob overkill. For now I have some 425's spare so I'll just use those to get the x,y built until funds allow for the new set.
Once I start pulling mine apart I'm thinking of weighing the head and fitting a piston system. Also doing the 'roller blind' mod on the Z bellows. I only get 165mm with the stock one fitted and I ideally need to get it to go to 180mm

On my small mill I have 425oz steppers, With 5mm ballscrews I can only get to 1500mm/min rapids before I start losing steps/reliability.
My theory is that on a machine that's around 100% bigger in weight/size. If I got for motors 150% bigger then I should achieve 50% more speed so 2000mm/min rapids shouldn't be a problem.

If I had the money I'd be looking at closed loop with servos. But there again looking at their torque size (2.9nm ish) and rpm (3000 ish) they definitely want a 2:1 belt system to make full use of their speed potential.
I mean if one of those is direct driven on a 5mm pitch screw you'd have a max of 15,000mm/min rapid available! crazy.

The way it looks to me is:
If you don't need huge speeds but want as much accuracy as poss then something like option1.
If you don't need huge speeds and want accuracy that's 'close enough' then something like option2.
If you want speed and accuracy then closed loop 3000rpm servo with 2:1 belt drive.

[davlovsky]

Thank you so much for the reply. Speed isn't really an issue, so I'm thinking of just going with the steppers.
I've one last question. The mill comes with a spindle that has the control (VFD?). In order to properly retrofit a CNC conversion kit to the mill, I would need to have a breakout board that would be able to interface with the spindle electronics (VFD?) so that it can start/stop, control the speed, etc., correct?
If I'm using Mach3/Mach4, what kind of breakout board do you recommend that would allow me to control the spindle?

Here is my (more-or-less) finalized list for the electronics:
(1) Nema 34 1200 oz/in 6amp stepper motor (z-axis)
(2) KL-8070D DSP-based driver for (1)
(3) Nema 23 570 oz/in stepper motor (x- and y-axes)
(4) KL-5056 5.6A drivers for (3)
(5) 60VDC/10A Switching power supply

The only missing piece is the breakout board. I just need something that would be able to work with my motors, Mach3/4 and the original Grizzly 0619 spindle/VFD.

[davlovsky]

So, I got the X3 w/ premium ball screws.
And then everything in the list above.
The controller I got was this one.

I'm hoping to have everything up-and-running by the month's end.
Will probably be building an enclosure out of aluminum extrusion and adding a simple coolant system.

Question: Have automatic tool changers ever been used on these Grizzly mills? I've seen ones that are around $2000 (way too much), but are way over-powered for what I do. But I was thinking it'd be nice to have one. Are there lower-cost automatic tool changer spindles available for around $500 that would fit on this Grizzly G0619?


Now the hard part: waiting

[seanano]

The KL-5056 drives have a max of 50VDC so they won't work with the 60VDC power supply listed. If you want to use a single power supply for your steppers then you'll need to use a lower voltage power supply (48VDC) or get higher voltage drivers for the X and Y axes (KL-6050 or bigger).

[davlovsky]

The KL-5056 drives have a max of 50VDC so they won't work with the 60VDC power supply listed. If you want to use a single power supply for your steppers then you'll need to use a lower voltage power supply (48VDC) or get higher voltage drivers for the X and Y axes (KL-6050 or bigger).

Thanks for the reply. I actually did notice that before ordering.
I ended up going with this one.

[dazp1976]

The KL-5056 drives have a max of 50VDC so they won't work with the 60VDC power supply listed. If you want to use a single power supply for your steppers then you'll need to use a lower voltage power supply (48VDC) or get higher voltage drivers for the X and Y axes (KL-6050 or bigger).

Only trouble with these builds.
I have various 36v, 60v and 12v power supplies in the box thus far. Prob need a 5v as well .
I'd prob benefit from swapping out the 36v to 48v instead though.
That's another reason why I'm going all 34 size later, keep it all at the same 60v level.

[davlovsky]

Those were my thoughts as well. With that X3 kit, I don't think it'd be that difficult to machine a couple of adapter to fit Nema 34s to the x- and y-axes.
Then all you'd need are some new couplers.

[dazp1976]

So, I got the X3 w/ premium ball screws.
And then everything in the list above.
The controller I got was this one.

I'm hoping to have everything up-and-running by the month's end.
Will probably be building an enclosure out of aluminum extrusion and adding a simple coolant system.

Almost finished my enclosure from extrusion and sheeting that's sitting on a wooden leg frame, just need to do some doors.

Same as you I need to try and find information about integrating the spindle to Mach.

In terms of cooling some of the ones I've seen on the net are laughable. If it can't push out a chip then it's pretty useless. Some I've seen are £200 with only 1 nozzle output :nono:

I think I paid around £150 total for my scratch built one. Worth thinking about.
350w submersible pump, 30L bucket, ally to make a manifold for 2 jets and various hose connectors.
It has that much power I had to fit a valve setup to divert half the flow straight back to the bucket. Runs 2 nozzles atm and blasts chips away. When I move it to new one I'll put 2 more on and a 50L tank.

My filters are basically 3 plastic boxes for a 2 stage filter. 1 has 400 micron stainless steel mesh, the second has 200 micron mesh for fines and the 3rd is the drain off. Has a 4.5L chip capacity as is. They do need washing out often though. The 200 micron is so tightly packed it filters out the heavier way oil and builds up. At least in the last 2 years of use I've had no smells and no chips come back through

Testing the system prior to fitting. You can see the force it has:


My Sieg in it's early days after being thrown together.
https://www.youtube.com/watch?v=M-7kHfSkT9Y

I have moved the manifold block since then and fed some smaller tubing from there to the machine area.

[davlovsky]

Same as you I need to try and find information about integrating the spindle to Mach.

The called the company that I ordered all my parts from. I got a CNC controller with relays and spindle control.
There's a circuit diagram in the manual. You basically interface the board with the Grizzly's onboard VFD (Variable Frequency Drive).


I would also like to eventually add an MPG (Manual Pulse Generator) pendant -maybe a DIY. Have a 2-axis joystick controlling the x- and y-axes and a one-axis joystick controlling the z-axis. Maybe also have the rotary knobs as well.

That's a nice coolant system btw.
Saw your video too. That's a lot of coolant you're running -remind me of when I was working at my old job on a Haas.
But I do most low volume stuff, but still would like to have coolant, just not as much probably.
How do you protect your motors, electronics with so much coolant splashing around?

[davlovsky]

Same as you I need to try and find information about integrating the spindle to Mach.

The called the company that I ordered all my parts from. I got a CNC controller with relays and spindle control.
There's a circuit diagram in the manual. You basically interface the board with the Grizzly's onboard VFD (Variable Frequency Drive).


I would also like to eventually add an MPG (Manual Pulse Generator) pendant -maybe a DIY. Have a 2-axis joystick controlling the x- and y-axes and a one-axis joystick controlling the z-axis. Maybe also have the rotary knobs as well.

That's a nice coolant system btw.
Saw your video too. That's a lot of coolant you're running -remind me of when I was working at my old job on a Haas.
But I do most low volume stuff, but still would like to have coolant, just not as much probably.
How do you protect your motors, electronics with so much coolant splashing around?

[dazp1976]

The called the company that I ordered all my parts from. I got a CNC controller with relays and spindle control.
There's a circuit diagram in the manual. You basically interface the board with the Grizzly's onboard VFD (Variable Frequency Drive).


I would also like to eventually add an MPG (Manual Pulse Generator) pendant -maybe a DIY. Have a 2-axis joystick controlling the x- and y-axes and a one-axis joystick controlling the z-axis. Maybe also have the rotary knobs as well.

That's a nice coolant system btw.
Saw your video too. That's a lot of coolant you're running -remind me of when I was working at my old job on a Haas.
But I do most low volume stuff, but still would like to have coolant, just not as much probably.
How do you protect your motors, electronics with so much coolant splashing around?

Attachment isn't working Wanted to compare it to my PM25 clones one.
My BOB is one of these with relay + 0-10v onboard:

https://ae01.alicdn.com/kf/HTB10Im2X...-Isolation.jpg

Yeah the coolant system turned out pretty industrial
Motors are now covered using thin lexan and it seems to stay away from the machine speed controller on the side. Driver control box and PC are well above the whole thing on a shelf.

[davlovsky]

Try it again, this time as a .png:



From the looks of your circuit diagram, you have spindle control. Again, I'm pretty sure all you need to do is interface it with your mills VFD. You'll probably have to consult your breakout board's user manual for the correct wiring.

[maxspongebob]

That looks like it is going to be a really nice mill. The kit looks like good quality parts and workmanship.

As far as additional hardware I would add the following:
A smart controller. My choice would be an Ethernet Smooth Stepper or a Pokeys 57CNC. Both are smart controllers and have good tech support (very important).
Couplers. I would recommend spider couplers. Bigger is better, make sure it has a good solid attachment to the shafts. A setscrew is not the best, clamps are best. https://www.cnczone.com/forums/attac...d=380334&stc=1
Enclosure for electronics. Bigger is usually better, you never know what you will want to add inside.
Limit switches and home switches. These can be mechanical or electronic. Figure out how to mount them and then mill the parts you will need before you take your mill apart.
A pendant. Pick what software you want and then pick a pendant that is compatible. Nothing worse than having to move back and forth between mill and computer to jog to a location.
E-Stop switches.
Push button switches that you can mount at the machine to start/stop the cycle.
Cable guides.
A touch screen monitor and PC. I used an Intel NUC computer because it is so small but powerful.
Cabling. There will be lots of it. Some shielded, some not, some inside the enclosure some not.

Make a parts list and figure out what will go where.
Then layout the parts in the enclosure so that you get good air flow and simple wiring.
Make a wiring diagram or schematic that includes everything including grounding.


On my build I tried to simplify and standardize. I used NEMA 34's on all axis and chose Teknic ClearPath servos to eliminate a bunch of parts and wiring in the enclosure. For limit switches I used mechanical micro switches, but if doing it again, I would use Proximity sensors.

https://www.cnczone.com/forums/bench...are-posts.html

[davlovsky]

Servos would've been really, really nice.
And, yeah, I'll most likely be updating my x- and y-axes to Nema 34's in the near future.
The budget was ~$1500 to get 'er CNCed and around $500 for the enclosure and misc. parts.
I'll have more money to throw at this project in the future.

I'm going to model an 8020 enclosure in my CAD software.

The x- and y-axes motors are I got are Nema 23s, 570 oz/in dual shaft (I don't think they make those in single shaft).
I wanted to fabricate some kind of small enclosures for the x- and y-motors -either sheet metal or plastic, and have the other end of the shafts sticking out of the enclosures (making it coolant-tight) and attach the original grizzly hand wheels w/ revolving handles to the shafts so it could be operated manually...maybe... -all that would be contained in the larger, 8020 box, enclosing the entire mill. Have the monitor side-mounted to the 8020, and the pendant somewhere nearby.

For the manual pulse control (pendant), I was really liking my joystick idea for jogging (but also having the rotary dials also). I'll have to look into this more to see what's compatible with my BOB. Most likely I'll buy one that's compatible and then bring the connections out to the joysticks.

A probing routine and a fourth axis are also on the bucket list, the latter maybe just a simple planetary gear, Nema 34, mounted to a extra thick piece of aluminum or steel angle.

[davlovsky]

This is what I was talking about with the joystick idea. IDK if this is how this guy has it wired up, but basically want a 2-axis joystick for the x and y and a 1-axis joystick/toggle or even thumb/paddle switch for the z. But I think this looks sharp.

[dazp1976]

This is what I was talking about with the joystick idea. IDK if this is how this guy has it wired up, but basically want a 2-axis joystick for the x and y and a 1-axis joystick/toggle or even thumb/paddle switch for the z. But I think this looks sharp.

Personally I'm thinking a USB PC gamepad such as xbox style to work Mach3.
Program the buttons how I want then without the need to worry about BOB compatibility.