[rbraeking]

I am in the process of bench testing the new Hind Technology Gen-II controller. It requires no pc to operate. It has 32 inputs, 16 outputs, and 7 relay outputs. Plug usb keyboard and vga screen into controller.

Is anyone else looking at this controller? I'd like to hear from you.

Bob

[spumco]

I'd love to hear about your bench testing. I contacted CNC4PC and HTG directly recently when I stumbled across the controller.

It appears they're working on the additional features (4th/5th axis, conversational CNC, etc.) but with no specific delivery date. They've updated their web site a bit in the past couple of weeks.

My remaining questions:
- HTG published 100KHz frequency on all three axis.

Not sure how this jibes with them partnering up with DMM Tech and offering the nice range of DST/DHT servos and drives. I am a novice with CNC, but it seems that a 100KHz pulse rate is not suitable for a servo with a 16-bit (64k PPR?) encoder. Maybe my math is wrong, but at 3000RPM the encoder for a single axis would need something like 200MHz to keep up. What am I missing?

- No encoder feedback to the controller? I don't see axis feedback inputs, only the spindle. Again, maybe I'm missing something.

Maybe this is the ticket for a stepper-based system, but I'm curious how it flies with servos.

Please continue to post your experience. I'm considering a replacement system for my mill and am agonizing over the options. I really don't want to become a CNC design expert - but I also don't want to spend $$$ on a commercial turn-key system. I'm new enough at this that I'm not wedded to Mach3/4 or any other interface.

How's the interface? Anything irritating?

Thanks,
Spumco

[rbraeking]

Spumco,

Why do you need to run your servos at such a high speed on your x/y/z? My machine is set up with steppers but I am running my x/y at 2120 steps per inch with 1000 ipm maximum speed. That is a little over 35KHz which is well within the capability of the controller. If Mach3 works for you this controller should as Mach3 has a maximum kernel speed of 100khz.
Some of the advantages to the controller that I can see are:

1 No pc required. Which translates to less complicated setup. I run a wood router which generates a lot of dust despite my best dust collection efforts. My shop is not air conditioned in South Texas where the humidity never goes over 100%.....but not much under either. That is not a good environment for a pc. I never did like the pc concept because Windows® is so vulnerable to quirks and glitches.

2 Cost - I have not found any stand alone controller that is priced this reasonably. This one is less than the cost of a good pc/smooth stepper/control card combination. Others are 6 to 10 times the price.

3 Uncomplicated UI - Mach3 has a lot of UI features which are superfluous to normal operators.

4 The controller supplies the 0-10v spindle control internally. My other control cards have all needed a 10v supply input to them.

5 Input voltage can be up to 24v. That simplifies proximity limit switch installation and the number of DC power supplies needed in the control cabinet. My machine was supplied with 24v control power. 24v control is helpful because the HVAC industry uses 24v control which makes contactors and relays readily available.

I don't like the fact that the machine setup is metric despite being able to use imperial units in the run screen. I guess that the USA is the only country in the world using imperial measurements. Does that make me an American snob?

Bob

[arturod]

Spumco,

Yes, 100Khz is low, but it is really what you need on a regular mill or router to get a decent resolution. The idea is that you adjust the encoder resolution on the drive to match to the speed on the controller and the speeds you will be running at.

Arturo Duncan
Welcome to CNC4PC

[spumco]

Gents,

Thanks much for the responses.

As to the encoder/resolution question... I haven't purchased any servos with the encoders I mentioned, nor have I decided against the HTG controller (or any other for that matter). I was just trying to reconcile what appeared to me to be a significant difference between the DMM servos and the HTG controller frequency. Being an utter novice with just enough information to be dangerous, I was looking for a sanity check.

So, based on your responses, if one wants an encoder with a PPR appropriate to a 100Khz controller one should order a 1024 or similar PPR count for a 2k-3k RPM system? And the "16-bit" part in the DMM specifications means...what?

Regarding the other topics, I quite agree that a stand-alone controller is preferable for exactly the reasons you've illustrated, and the HTG in particular looks very attractive. I'm new enough at this to know I'm an utter retard; just past the 'don't let the smoke out of the wires' stage.

My machine has direct-drive steppers with the typical 1.8 degree steps and micro stepping drives. If I recall my Mach settings, I'm getting something like 23k steps per inch and this tells me I have roughly 5TPI ballscrews which is more or less in accord with their appearance (looked at, but not measured).

If I put servos on it and want 400IPM rapids, I'll need 2000RPM axis motors. This seems faster than is realistic for steppers and having a closed-loop system is attractive for obvious reasons. Once I started looking at servos I've been trying to learn as much about the realities as possible and the encoder PPR-to-controller frequency question came up in my mind.

Really not trying to hijack this thread with my own questions & issues. The HTG controller looks great, cheap, and just the ticket. The main reason I haven't just thrown money at CNC4PC 10 seconds after I saw the HTG thing is that I need a 4th axis and they haven't implemented it yet.

-Spumco

[arturod]

Spumco,

I am sorry for the confusion on the encoder resolution. No, you do not need special encoders, you can use the motors right of the shelf. You can configure the encoder resolution or electronic gearing on the drive.
So you already have a machine with steppers on it…. Adding encoder feedback will not improve the motor speed, it will just will prevent accidents from happening, they are still steppers and will lose torque as you gain speed. It is not clear to me what the objective is about updating the system. If the machine is running ok like it is now, then do not touch the power side, maybe update the drivers. If you need to improve the performance, then get the motors that will give you the performance that you are looking for. The real reason behind upgrading to servos may be that you need higher speeds, torque or reliability.

Do not forget, do not fix it if it is not broken….

Arturo Duncan
Welcome to CNC4PC

[rbraeking]

Speed is a function of both the motor speed and gearing. Realistically a stepper does not like to run fast so make up for that with mechanicals. Servos, i am told have a 'hunting' charactaristic which is detrimental to precision positioning. As long as steppers are not overloaded so that they skip steps they work fine and are more economical. There are hybrid steppers that have internal encoders which will stop the machine if they get out of step.

My router has rapids of 1000ipm and cuts at a max of 650ipm using steppers.
Bob

[spumco]

At the risk of this turning in to a total thread hijack, I'll throw up my thoughts. Please feel free to tell me to shut up and wait for Bob to post his thoughts on the Hind controller.

My mill is mostly working right now. The axis movements are reasonably precise - ground ballscrews and linear rails. The problems are noisy/vibrating steppers (actual), lost steps (potential/anticipated), and some wretched proprietary mill electronics (Mikini). The BLDC spindle motor is dodgy, and the spindle driver is absolute junk. I knew all this purchasing it and have budgeted for a complete retrofit.

I am in the process of replacing the spindle motor with a nice induction/VFD combo. Getting the mill controller to talk to the VFD and Mach is challenging, and if the proprietary controller dies I'm up the creek as it's unavailable at any price. So, while continuing to work on integrating the VFD (short term), I'm researching controller options as I expect the OEM thing to go up in flames. When it blows up, I'll need something - anything - and an all-in-one solution is more appealing than a BOB+ESS+PC+Mach3.

Having said all that, I have some basic options for different system arrangements. I want to cut anything, at any speed, with perfect accuracy; what compromises must I accept based on my budgetary and intelligence limitations?

Accuracy and motion control:
1. Uber-smart - Feedback on both the axis motors and glass/mag scales to compensate for thermal expansion & backlash, both tied to the motion controller. Expensive and I don't understand how to reconcile the two inputs so they don't fight each other.
2. Smart - Feedback on axis motors tied to driver/amplifier AND motion controller. Motion controller is able to use the feedback to adjust motion plot.
3. Smart-ish - Feedback on axis motors tied to driver/amplifier, but not controller. Controller assumes everything is going as planned until a following error is reported.
4. Dumb - system with no feedback. Steppers move a specific amount based on calibration and lost motion/errors are dealt with by scrapping parts or over-sizing/gearing the motors so there is never a lost step (short of a crash). This seems inefficient to have way over-sized motors just for want of axis feedback.

The limited time I've spent fiddling with or watching commercial V/HMC's indicate they use either #1 or #2, depending on cost.
Any controller than can accept axis feedback can be a #2 with the right equipment (kflop, Galil, CSMIO, LinuxCNC, commercial stuff, etc.). Not that every option will make sue of the feedback effectively, I'm sure.
The Hind controller, as well as anything Mach3 + BOB, is #3, as far as I know.
Right now my system is #4.

Question - assuming I decide to replace the OEM electronics, is there any significant benefit to going with a #2 system vs. a #3? At significantly increased cost and/or complexity?

Speed
Are my axis steppers powerful/fast enough to achieve the appropriate feedrates for various materials - without losing steps - given my spindle speed and HP limitations? I suspect not, so in addition to researching motion controllers I'm looking at axis drive options. i agree with Arturo's earlier statement "don't fix what isn't broken" and I see no reason up upgrade the existing steppers or drivers unless I move to a system with feedback (either hybrid steppers or servos). My limited research indicates that there is no significant price difference between name-brand closed-loop steppers and DMM servos with the same frame size.

Given the minimal price difference between closed-loop steppers and servos, why would I want to use steppers?

So getting back to the Hind controller... It appears that i can use it to drive my VFD, and that it will play just fine with my existing steppers/drivers. if I upgrade to servos now or later, it'll still work fine and I won't need to change any significant hardware - just pitch the steppers/drive and buy some servos & amplifiers. This is fundamentally why the Hind is attractive to me as I can get rid of the OEM electronics, get rid of Mach and Windows, and I haven't painted myself in to a corner for future axis upgrades.

Hence my questions to Arturo & Hind directly as well as in this thread. Right now I have a working 4th axis (not that I'm competent to use it effectively) and I also have conversational CNC in Mach3. The Hind has neither at this moment, but are promised. The upside is that I can probably get the new VFD integrated with the Hind faster than I can get a custom interface board that connects the VFD to the OEM electronics.

If I switch to the Hind controller before the OEM electronics blow up, what are the downsides? What additional expenses am I not seeing besides needing a new MPG?

Whew.

-Spumco

[warrenb]

I've been looking at that control to replace my ancient Centroid on a Bridgeport Boss. The only complaint I can muster (without having used it) is that it doesn't support touch screens. For the price of that controller and 3 brand new AC servos I can replace the Centroid setup for about 1/2 of the upgrade Centroid offers.
After playing around with DC servos and Mach, no more of that for me... I need a professional machine to compliment my industrial CNCs for secondary ops. But I can't justify the expense of the Centroid upgrade at $5500 for a $1500 machine. Total cost of the HIND and New Servos about $3000

I haven't pulled the trigger yet but am very close when a few checks clear.

[rbraeking]

Lets address one at a time.

Noisy steppers: What are you using to get signals from the computer to the controller? I had that problem until I installed a smooth stepper which contains a buffer. Parallel cables are problematic in that they are slow and deliberate. I have yet to attach steppers to the Hind controller but I should do so this weekend. I hypothesize that they will be smooth because the controller is not running all the Windows® background junk that takes memory. Parallel ports are low priority in Windows®

I'm guessing that you are running a metal working mill. Correct me if I am wrong. An induction motor and VFD is a great advantage over DC motor/drives. The Hind controller has no problem running a VFD and it has its own 10v embedded power supply so no additional power supply is needed.

You need a feeds and speeds calculator. There is subscription software available called GWizard Calculator. I use it regularly to avoid rubbing and maximize my cutting speeds.

Accuracy: This depends on mechanical backlash mostly. As long as steppers are not overloaded they will not skip steps. My overloads are almost always operator error. Trying to plow through 3/4 plywood full depth at 650ipm will definitely overload the steppers but the racket will give the operator a clue. Hybrid steppers will stop when they skip. Servos will try to keep up but cost is more. Your choice. My system is straight stepper but I built a homebrew with hybrids. My feeling was that I wasted money on the hybrids once I sized my steppers properly. Note that a lot of microstepping will rob lots of power. If you can tune the mechanicals for zero microstepping you will have a stronger system. Actually servo feedback goes to the servo driver in most cases. The Hind controller does have a provision for reading feedback from your spindle drive.

Servos vs Steppers. Servos work a bit differently. The controller tells it where to go and the motor/driver moves until the feedback tells it that it has arrived. They hunt a little. Steppers are positive motion. When you tell them to move 1400 steps they move exactly 1400 steps (unless you overload them). For precision I would recommend steppers. Hybrids if you are running expensive materials and want to stop the machine on overload.

Hind is working hard to get full features available. They just added a biggie for me - probing. As yet they do not have the macro screen running so I will write a g-code routine to probe for z-zero and keep it on my stick.

4th and 5th axis as well as axis slaving I am told is coming very soon.

The Hind manual has a wiring diagram for MPG. You may be able to use your current one. I use a wireless keyboard and the JOG function. Check the online manual. Arturo has a link on his product page.

Keep in mind that the Hind Gen-II has only been available in the USA for a couple of weeks. The concept is better than anything I have seen and I am sure that they will be fully functional very shortly.

If you want touch screen it may work. They have tried it at Hind. As long as there is a USB interface. I'm kind of old school. I prefer a keyboard and plain screen. I can't see $400 for a touch screen and putting it out in my shop.

Bob

[mactec54]

I'd love to hear about your bench testing. I contacted CNC4PC and HTG directly recently when I stumbled across the controller.

It appears they're working on the additional features (4th/5th axis, conversational CNC, etc.) but with no specific delivery date. They've updated their web site a bit in the past couple of weeks.

My remaining questions:
- HTG published 100KHz frequency on all three axis.

Not sure how this jibes with them partnering up with DMM Tech and offering the nice range of DST/DHT servos and drives. I am a novice with CNC, but it seems that a 100KHz pulse rate is not suitable for a servo with a 16-bit (64k PPR?) encoder. Maybe my math is wrong, but at 3000RPM the encoder for a single axis would need something like 200MHz to keep up. What am I missing?

- No encoder feedback to the controller? I don't see axis feedback inputs, only the spindle. Again, maybe I'm missing something.

Maybe this is the ticket for a stepper-based system, but I'm curious how it flies with servos.

Please continue to post your experience. I'm considering a replacement system for my mill and am agonizing over the options. I really don't want to become a CNC design expert - but I also don't want to spend $$$ on a commercial turn-key system. I'm new enough at this that I'm not wedded to Mach3/4 or any other interface.

How's the interface? Anything irritating?

Thanks,
Spumco

The only thing you were missing in reference to the 200KHz, is Electronic Gearing which is built into most AC Servo Drives just so they can run on lower frequencies, and still have max performance

You still have the same Encoder resolution, when you use the Electronic Gearing in there system 100Khz can drive the servo Motor at full RPM, I myself would not buy the controller, 100Khz is to low for todays systems even some of the cheaper controls run at 125Khz

[spumco]

Lets address one at a time.

Noisy steppers: What are you using to get signals from the computer to the controller?

Bare-bones WinXP built-in PC that came with the mill. There's a proprietary BOB & manual controller board that hands off control to the PC/Mach3 when you put it in CNC mode. Manual mode permits spindle operation and MPG operation, but no native Gcode input. Connected via parallel port, no hardware motion controller (ESS or USBSS)

I'm guessing that you are running a metal working mill. Correct me if I am wrong.

Correct. 9x16 ish travels, linear rails, 5k RPM BLDC spindle. Pretty rigid frame for this size. R8 collet, using Royal QC system that came with it. No ATC. 4th axis is a stepper 90:1 rotary table, 10RPM max. This is the now-defunct predecessor to the biggest SkyFire mill.

You need a feeds and speeds calculator. There is subscription software available called GWizard Calculator. I use it regularly to avoid rubbing and maximize my cutting speeds.

Agree. Trialed GW and am trialing FSW. One or the other will get some money from me shortly. CNCCookbook is a daily stopping point for me. I should give him some money just for squatting on his site so frequently

Accuracy: This depends on mechanical backlash mostly. As long as steppers are not overloaded they will not skip steps. My overloads are almost always operator error. Trying to plow through 3/4 plywood full depth at 650ipm will definitely overload the steppers but the racket will give the operator a clue. Hybrid steppers will stop when they skip. Servos will try to keep up but cost is more. Your choice. My system is straight stepper but I built a homebrew with hybrids. My feeling was that I wasted money on the hybrids once I sized my steppers properly. Note that a lot of microstepping will rob lots of power. If you can tune the mechanicals for zero microstepping you will have a stronger system. Actually servo feedback goes to the servo driver in most cases. The Hind controller does have a provision for reading feedback from your spindle drive.

All commercial metal mills/lathes I've come across use servos, and I do intend to machine tough, expensive materials. If I do upgrade the axis motors and/or drives, I'll likely get some Nema34 750w DMM servos - bolt-on X/Y with a coupling change and some surgery on the Z-axis

Servos vs Steppers. Servos work a bit differently. The controller tells it where to go and the motor/driver moves until the feedback tells it that it has arrived. They hunt a little. Steppers are positive motion. When you tell them to move 1400 steps they move exactly 1400 steps (unless you overload them). For precision I would recommend steppers. Hybrids if you are running expensive materials and want to stop the machine on overload.

Again, any axis upgrade or replacement due to dead components will include feedback/encoders. I don't see the point of saving a hundred or two per axis when closed-loop is not extraordinarily expensive these days. The question in my mind is whether it's worth the headache and/or cost to select a controller that uses the axis feedback for motion control adjustment. I suspect not.

Hind is working hard to get full features available. They just added a biggie for me - probing. As yet they do not have the macro screen running so I will write a g-code routine to probe for z-zero and keep it on my stick.

4th and 5th axis as well as axis slaving I am told is coming very soon.

The Hind manual has a wiring diagram for MPG. You may be able to use your current one. I use a wireless keyboard and the JOG function. Check the online manual. Arturo has a link on his product page.

Keep in mind that the Hind Gen-II has only been available in the USA for a couple of weeks. The concept is better than anything I have seen and I am sure that they will be fully functional very shortly.

If you want touch screen it may work. They have tried it at Hind. As long as there is a USB interface. I'm kind of old school. I prefer a keyboard and plain screen. I can't see $400 for a touch screen and putting it out in my shop.

Already have a USB touchscreen, so no extra cost there. Good to know about the other features, and of course Hind & CNC4PC have been pretty informative with my various inquiries. It looks like a killer setup.

Bob

Thanks for the continued education.
-Spumco

[spumco]

The only thing you were missing in reference to the 200KHz, is Electronic Gearing which is built into most AC Servo Drives just so they can run on lower frequencies, and still have max performance

You still have the same Encoder resolution, when you use the Electronic Gearing in there system 100Khz can drive the servo Motor at full RPM, I myself would not buy the controller, 100Khz is to low for todays systems even some of the cheaper controls run at 125Khz

THIS.

Thank you. As I've been educating myself I came across the concept of electronic gearing, but associated it (in my mind) only with gearing the spindle to an axis - such as for tapping or 4th axis threading. Didn't occur to me that the drive could be set up such that the step/dir from the controller could be translated in the drive to some gearing where 1 input pulse = X output pulses.

So... why, given that the electronic gearing makes full-speed possible at some reduced (but acceptable) resolution, is a 100Khz control too low?

Regards,
Spumco

[mactec54]

THIS.

Thank you. As I've been educating myself I came across the concept of electronic gearing, but associated it (in my mind) only with gearing the spindle to an axis - such as for tapping or 4th axis threading. Didn't occur to me that the drive could be set up such that the step/dir from the controller could be translated in the drive to some gearing where 1 input pulse = X output pulses.

So... why, given that the electronic gearing makes full-speed possible at some reduced (but acceptable) resolution, is a 100Khz control too low?

Regards,
Spumco

The other part that comes into play is what the Drive input voltage is, as to how fast the servo motor can run , the old 48v Dyn2 Drives with a 750w motor could only run at around 1150 RPM max , a 400w servo motor on the same Drive I have had them up to 2750 RPM it did not matter what the step/dir rate was the limiting factor was voltage the 230v Drives have no problem in getting max performance from any of the Drive rated motors

[my-cnc]

I've been looking at that control to replace my ancient Centroid on a Bridgeport Boss. The only complaint I can muster (without having used it) is that it doesn't support touch screens. For the price of that controller and 3 brand new AC servos I can replace the Centroid setup for about 1/2 of the upgrade Centroid offers.
After playing around with DC servos and Mach, no more of that for me... I need a professional machine to compliment my industrial CNCs for secondary ops. But I can't justify the expense of the Centroid upgrade at $5500 for a $1500 machine. Total cost of the HIND and New Servos about $3000

I haven't pulled the trigger yet but am very close when a few checks clear.

We develop myCNC controls. It does support touch screen. Pulse-Dir frequency is 3MHz for simultaneous 4-6 axes interpolation. Price starts from $500 (for 4 axes pulse-dir, 3MHz).
We have analogue +-10V control, encoder inputs and closed-loop as well.
What do you think about it?

https://youtu.be/fDK1FsdqFWY
(on the video new ET7 board, 6 axes pulse-dir, 3 encoder inputs, 16 in/16out)

[mactec54]

We develop myCNC controls. It does support touch screen. Pulse-Dir frequency is 3MHz for simultaneous 4-6 axes interpolation. Price starts from $500 (for 4 axes pulse-dir, 3MHz).
We have analogue +-10V control, encoder inputs and closed-loop as well.
What do you think about it?

https://youtu.be/fDK1FsdqFWY
(on the video new ET7 board, 6 axes pulse-dir, 3 encoder inputs, 16 in/16out)

That looks like it could be a good package, can it use any other control software

[hanermo]

Very much.
I run 500 kHz now, and expect to move to 2-4Mhz soon.

Using 10.000 count encoders on step dir servos, at 1:3 - 1:2 gearing.
Typical 0.2 micron, or 0.0002 mm step rate, or about 127.000 steps/inch.
220V ac servos.
Step size =/= resolution.
Resolution=/= accuracy.
Step size=> better accuracy, smoothness, surface finish.

And going up, 4 times or so.
Lathe.

For basic mill, at 1:2, 125 kHz is just, barely, adequate. Losing 1/2 of servo top speed, mostly immaterial even on my huge, big, commercial level machine (1600 mm x 1000 mm y, 400 mm z).
Step rate and speed is overrated by 10x.
Rigidity and mass is 10x more important.

THIS.

So... why, given that the electronic gearing makes full-speed possible at some reduced (but acceptable) resolution, is a 100Khz control too low?

Regards,
Spumco

[my-cnc]

So... why, given that the electronic gearing makes full-speed possible at some reduced (but acceptable) resolution, is a 100Khz control too low?
Regards,
Spumco

If you use electronic gears, then 100KHz is not "too low", but "too rough". Full speed is not a problem, but you may loose smooth motion and precision.

[my-cnc]

That looks like it could be a good package, can it use any other control software

No, myCNC boards work with myCNC software. However third-party software can have access to the system over Network API provided.

[Hind_Technology]

Thanks for the great review and feedback Bob.

We have added your request of having imperial units in the F1-Setup screen and it will be released in the upcoming version with a all new F1-Setup screen setup.