Author Topic: Right motors, PSU for CNC mill  (Read 1170 times)

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Online 3dgeo

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Re: Right motors, PSU for CNC mill
« Reply #25 on: September 20, 2019, 11:22:45 pm »
i already have few 12V PSU to play with, and its also easily available in form of PC ATX PSU sold everywhere locally. mosfets in the stepper driver maybe happy with higher voltage, who knows?
I have many PC PSUs as well, they should be OK for testing. I agree that for a big CNC 12V is not enough, tho my choice would be to go with 48V or more, I actually found cheap enough toroidal transformer, so making my own PSU is not out of the question yet.

about trusting the china design, well maybe there's few caps and mosfets need replacement in case of smoke comes out, but i'm not going to trust brand name either. i had Gigabyte brand ATX PSU that failed much earlier than no name brand PSU, i have HP (USA?) Z800 server PC workstation coming this way with PSU issues discussed everywhere in the net, so even USA brand is not a bulletproof product. but everybody is free to choose what they like.
I have no PSU design experience, bus as far as I understand brand like MeanWell ads more protection features as well. Talking about good known brands making mistakes – I had 500Eur worth brand new Asus server/workstation motherboard literally exploding to my face – one cap blew up and flied straight to my neck and burned my neck a little (no permanent damage). And it wasn't my mistake, something went wrong with CPU power delivery. It killed one of two 8 core CPUs in the process. Tho Asus support was good, they dispatched new motherboard right away, delivery person whom delivered new board took old board and dead CPU. Asus compensated for dead CPU as well. I have to mention one bad thing – that "new" board was refurbished and signs of wear was visible, so I asked them to fix my broken board that was actually new, not refurbished. And they did, they send back my fixed board and took replacement back.
The moral is – no one is perfect, tho extra cost for well known brand includes better support, arguably better components, features and they need to keep their name "clean" even in bad situations :)

Z800? Ancient 1366 double socket? I have Intel S5520SC motherboard and couple of X5647 collecting dust  ;D

yes thats why i'm planning to mod it to be connected to a dc or bldc motor later to become a lathe, and also thats why i have to go to the hassle to build a converter circuit to read its rpm to thermistor voltage (close loop rpm control) to make it reprap/marlin compatible, a stepper motor wont need such converter.
I can't understand why you want to put a lathe on your CNC mill ??? I'm not an expert on the matter but if you make your own ESC you can track motor spin speed via MCU or hack prebuilt driver MCU to get RPM, check Electronoob videos



that's fundamental to how stepper drivers work. Steppers are big inductors so the higher the driver voltage the faster you can reach max current, iow the higher the voltage the faster you can step without losing all your torque. I'd say 24V is a bare minimum

Any useful links for dummies on this topic?  ;D

P.S. langwadt – I really want to build stepper driver board with powerstep01 as well, do you have any notes, warnings on PCB design? Any interference, instability issues that I should know about? How far from recommended design yours PCB is? I'm not sure at this point, but I want to try to make it modular – every driver on its own PCB and use aviation plugs and solder their wires as close to powerstep01 as possible, but still leave plenty space for additional aluminum heat sink if needed. What you think about this? I bet those drivers work way more silent and smoother than cheap drivers...
« Last Edit: September 20, 2019, 11:41:13 pm by 3dgeo »
 

Offline langwadt

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Re: Right motors, PSU for CNC mill
« Reply #26 on: September 21, 2019, 10:34:02 am »

that's fundamental to how stepper drivers work. Steppers are big inductors so the higher the driver voltage the faster you can reach max current, iow the higher the voltage the faster you can step without losing all your torque. I'd say 24V is a bare minimum

Any useful links for dummies on this topic?  ;D

P.S. langwadt – I really want to build stepper driver board with powerstep01 as well, do you have any notes, warnings on PCB design? Any interference, instability issues that I should know about? How far from recommended design yours PCB is? I'm not sure at this point, but I want to try to make it modular – every driver on its own PCB and use aviation plugs and solder their wires as close to powerstep01 as possible, but still leave plenty space for additional aluminum heat sink if needed. What you think about this? I bet those drivers work way more silent and smoother than cheap drivers...

nothing special about the pcb, main objective was that I wanted four drivers with connectors fit in a 100mm wide box.
if you want modular just buy some X-NUCLEO-IHM03A1

they aren't particularly smooth or silent, if you want that tmc5160/tmc2160 with external fets is a better choice and they have standard step/direction drive so will work with standard motion controllers

 

Offline Mechatrommer

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Re: Right motors, PSU for CNC mill
« Reply #27 on: September 21, 2019, 12:05:23 pm »
I can't understand why you want to put a lathe on your CNC mill ??? I'm not an expert on the matter but if you make your own ESC you can track motor spin speed via MCU or hack prebuilt driver MCU to get RPM
because i want a unified solution for my CNC, it can be switched between lathe and 4th axis CNC by switching the motor. usually lathe cutter is manually controlled, this time i want the CNC head (X and Z axis movement) as automated cutter. maybe i can save up later to get $1000+ dedicated mini lathe machine, but i want to see possibility with this project, if its possible then i dont have to buy dedicated lathe machine. if not, then its another waste of money that i will try to repurpose the parts as much as i can. this is try and error i'm no expert i can be wrong. btw, the 4th axis arrived and tested yesterday, real bulky, even the tailstock that came with it (125mm+ length). i have to arrange properly or find a better way of locking it on to fit on my limited 6040 platform. ymmv.

about the RPM detector. i want to make an emulator board for 3d printer marlin FW that i'm planning to use, maybe if its done then it will become clearer to you. it will emulate voltage output produced by 3d printer thermistor with 4.7Kohm pull up to 5V. PWM from marlin/arduino board that is used to control heat element will be used to emulate motor control by slowly ramping up or down, similar to heat element respond. and later i will try to increase freq of control loop respond etc. anyway this is try and error again no hard prove its going to work, only bragging about my plan. thanks for the ESC RPM hack link, but i believe i will need extra effort and pcb too if i'm going that route, to emulate ESC to make compatible with marlin, but BLDC motor is a nice option. i have few china ESC around for my future drone project, so i can grab one of them if i want to. cheers and sorry my english.
« Last Edit: September 21, 2019, 12:07:49 pm by Mechatrommer »
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Offline SparkyFX

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Re: Right motors, PSU for CNC mill
« Reply #28 on: September 21, 2019, 02:20:47 pm »
4th axis or turning will sooner or later require the spindle to be indexable without changing setup, mostly for live tooling (think hole patterns or keyslots), maybe for feeding stock. An encoder might be the better choice.
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Online 3dgeo

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Re: Right motors, PSU for CNC mill
« Reply #29 on: September 21, 2019, 05:58:01 pm »
nothing special about the pcb, main objective was that I wanted four drivers with connectors fit in a 100mm wide box.
if you want modular just buy some X-NUCLEO-IHM03A1
Did you use regular copper thickness or double? Do you have an idea what max current they can drive with your PCB design with acceptable temperature?
After making it how do you feel – is it worth the time? I know there is X-NUCLEO-IHM03A1, but according to ST they are only for testing only...
You mind sharing machine you using it on?

they aren't particularly smooth or silent, if you want that tmc5160/tmc2160 with external fets is a better choice and they have standard step/direction drive so will work with standard motion controllers
Why they are not smooth or silent? They have 128 microstepping, even tho it isn't 256, but still, they should be silent enough, what gives?
tmc5160/tmc2160 adds an extra step – figuring out right mosfets, and I'm fine with SPI, I actually prefer SPI instead of step/direction.


because i want a unified solution for my CNC, it can be switched between lathe and 4th axis CNC by switching the motor. usually lathe cutter is manually controlled, this time i want the CNC head (X and Z axis movement) as automated cutter. maybe i can save up later to get $1000+ dedicated mini lathe machine, but i want to see possibility with this project, if its possible then i dont have to buy dedicated lathe machine. if not, then its another waste of money that i will try to repurpose the parts as much as i can. this is try and error i'm no expert i can be wrong. btw, the 4th axis arrived and tested yesterday, real bulky, even the tailstock that came with it (125mm+ length). i have to arrange properly or find a better way of locking it on to fit on my limited 6040 platform. ymmv.
1000 for lathe? Is it made from gold? :D Lathe sized like your 4 axis should cost like 200 buks... I still can't understand why you need lathe on CNC machine, just use your 4 axis and stepper motor to rotate it slowly – let milling bit do the job. If you really want CNC lathe just buy dedicated lathe and add XY axis to it to make it CNC...
 

Offline langwadt

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Re: Right motors, PSU for CNC mill
« Reply #30 on: September 21, 2019, 06:29:53 pm »
nothing special about the pcb, main objective was that I wanted four drivers with connectors fit in a 100mm wide box.
if you want modular just buy some X-NUCLEO-IHM03A1
Did you use regular copper thickness or double? Do you have an idea what max current they can drive with your PCB design with acceptable temperature?
After making it how do you feel – is it worth the time? I know there is X-NUCLEO-IHM03A1, but according to ST they are only for testing only...
You mind sharing machine you using it on?

they aren't particularly smooth or silent, if you want that tmc5160/tmc2160 with external fets is a better choice and they have standard step/direction drive so will work with standard motion controllers
Why they are not smooth or silent? They have 128 microstepping, even tho it isn't 256, but still, they should be silent enough, what gives?
tmc5160/tmc2160 adds an extra step – figuring out right mosfets, and I'm fine with SPI, I actually prefer SPI instead of step/direction.

just standard copper. I  don't know what current they can handle but they are fine for my ~4A need, above that the small current sense resistors I used are probably at the limit.

as with most diy electronics, if you have to ask if it is worth the time you shouldn't be doing it

ST says it is for testing only because they haven't bother with all the approval testing and they sell them at give away prices

The machine is cobbled together from aluminium extrusions, mgn12 rails, 1204 ball screws and an 800W spindle

they are smooth and when milling you can't hear them, but at stand still they hiss

there is no advantage in needing spi for direction and it means it won't work with any standard motion controller code

 

Online 3dgeo

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Re: Right motors, PSU for CNC mill
« Reply #31 on: September 21, 2019, 10:06:29 pm »
just standard copper. I  don't know what current they can handle but they are fine for my ~4A need, above that the small current sense resistors I used are probably at the limit.
Yeah, I don't think my motor will use more than 4A, so I can do 10x10cm as well, tho I might make it from thicker copper. I looked at external mosfets – suitable ones cost a LOT, 36 fets in total – not worth it in this case, so I will stick with all in one chip.

as with most diy electronics, if you have to ask if it is worth the time you shouldn't be doing it
I rephrase it – does it works as you expected? Any regrets, design mistakes?  ;D

The machine is cobbled together from aluminium extrusions, mgn12 rails, 1204 ball screws and an 800W spindle
they are smooth and when milling you can't hear them, but at stand still they hiss

I'm considering mgn12 and ball screws, but I'm not sure they worth that extra cost compared to regular 8mm lead screw and C beams with plastic wheels. I've seen videos that mgn12 on aliexpress are junk, that's why I'm hesitating, how do they work for you and where did you buy them?

there is no advantage in needing spi for direction and it means it won't work with any standard motion controller code
Well, I didn't dig in to powerSTEP01 SPI features, but I'm guessing that stalling detection and other features are communicated via SPI and interrupt pin. Plus I need to learn Gcode anyway, so writing my own controller code to work with SPI is not an issue. Also I just like fancyness of SPI  ^-^
 

Offline langwadt

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Re: Right motors, PSU for CNC mill
« Reply #32 on: September 21, 2019, 11:16:51 pm »
just standard copper. I  don't know what current they can handle but they are fine for my ~4A need, above that the small current sense resistors I used are probably at the limit.
Yeah, I don't think my motor will use more than 4A, so I can do 10x10cm as well, tho I might make it from thicker copper. I looked at external mosfets – suitable ones cost a LOT, 36 fets in total – not worth it in this case, so I will stick with all in one chip.

as with most diy electronics, if you have to ask if it is worth the time you shouldn't be doing it
I rephrase it – does it works as you expected? Any regrets, design mistakes?  ;D

The machine is cobbled together from aluminium extrusions, mgn12 rails, 1204 ball screws and an 800W spindle
they are smooth and when milling you can't hear them, but at stand still they hiss

I'm considering mgn12 and ball screws, but I'm not sure they worth that extra cost compared to regular 8mm lead screw and C beams with plastic wheels. I've seen videos that mgn12 on aliexpress are junk, that's why I'm hesitating, how do they work for you and where did you buy them?

there is no advantage in needing spi for direction and it means it won't work with any standard motion controller code
Well, I didn't dig in to powerSTEP01 SPI features, but I'm guessing that stalling detection and other features are communicated via SPI and interrupt pin. Plus I need to learn Gcode anyway, so writing my own controller code to work with SPI is not an issue. Also I just like fancyness of SPI  ^-^

you can get suitable FETs $0.20, the dual dual fet used on the TMC5160-stepStick is ~$0.50

it works as expected, only mistake was two swapped pins on a uart connector. I would have like more of the unused pins on the CPU to be accessible and I should have kept the option to run the motors at higher voltage

even bad mgn12/ballscrews are miles better than plastic wheels on c-beam and lead screws, I bought them from robotdigg
 
I also bought some reasonable nice hgh15 rails on ebay, 2*1500mm + 4 carriages for ~100gbp

SPI is nice for setting currents and reading errors, but for direction it is a hassle, and it has nothing to do with gcode, it is the
firmware that needs modifications

I never got the stall detection to work on the powerstep01, the datasheet it limited on how should be done (to say the least) and
I'm not even sure it works when not using the internal motiongenerator
 

Online 3dgeo

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Re: Right motors, PSU for CNC mill
« Reply #33 on: September 22, 2019, 03:20:32 am »
you can get suitable FETs $0.20, the dual dual fet used on the TMC5160-stepStick is ~$0.50
I think it defeats the purpose of using external fets if fets are that puny. If go with external fets than go all out and use something like IPT015N10N5 tho I bet TMC5160 would choke trying to drive 4 of those beasts with 16000pF capasitance each  >:D Even if it can drive those puppies – total mosfet cost would be 130 usd. Ok, I know those are overkill, but I don't see any point of using small external fets with high resistance.
I guess all come to programming...

it works as expected, only mistake was two swapped pins on a uart connector. I would have like more of the unused pins on the CPU to be accessible and I should have kept the option to run the motors at higher voltage
Swapping uart pins – so common mistake... :D Why didn't you break all pins out? I always do, even if I'm not using them... Whats is limiting the voltage? This is one of the features I like about powerSTEP01 drivers, their max voltage is 85V. I want to have option to drive control board from 60 to 80V.

even bad mgn12/ballscrews are miles better than plastic wheels on c-beam and lead screws, I bought them from robotdigg
Are you sure about this? Cos I think it is way easier to make round plastic wheels and aluminum profiles with high precision than to make rails and keep them straight while shipping. And even if their precision are the same, price difference is huge. I really should go to dedicated CNC forum to find this out to be honest...



I also bought some reasonable nice hgh15 rails on ebay, 2*1500mm + 4 carriages for ~100gbp
This video is why I'm so skeptic about rails:



SPI is nice for setting currents and reading errors, but for direction it is a hassle, and it has nothing to do with gcode, it is the
firmware that needs modifications

I never got the stall detection to work on the powerstep01, the datasheet it limited on how should be done (to say the least) and
I'm not even sure it works when not using the internal motiongenerator

Are you saying that powerSTEP01 has issues what comes to programming?  If so than it's a deal breaker, bin there (and partially still am) with other chip whom documentation sucks and even manufacturer support can't help with the matter...

Do TMC5160 have issues/are pain to program as well?
« Last Edit: September 22, 2019, 03:26:28 am by 3dgeo »
 

Offline langwadt

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Re: Right motors, PSU for CNC mill
« Reply #34 on: September 22, 2019, 03:54:05 am »
you can get suitable FETs $0.20, the dual dual fet used on the TMC5160-stepStick is ~$0.50
I think it defeats the purpose of using external fets if fets are that puny. If go with external fets than go all out and use something like IPT015N10N5 tho I bet TMC5160 would choke trying to drive 4 of those beasts with 16000pF capasitance each  >:D Even if it can drive those puppies – total mosfet cost would be 130 usd. Ok, I know those are overkill, but I don't see any point of using small external fets with high resistance.
I guess all come to programming...

the fets on the stepstick are 12A and ~6mOhm apart from the 40V rating much more than that would be pointless

it works as expected, only mistake was two swapped pins on a uart connector. I would have like more of the unused pins on the CPU to be accessible and I should have kept the option to run the motors at higher voltage
Swapping uart pins – so common mistake... :D Why didn't you break all pins out? I always do, even if I'm not using them... Whats is limiting the voltage? This is one of the features I like about powerSTEP01 drivers, their max voltage is 85V. I want to have option to drive control board from 60 to 80V.

breaking out the pins take space and even more if they have to go to a reasonable connector
the powersupplies are limited to ~30V input, I had intended to split the input in two, so the motor voltage was separate

even bad mgn12/ballscrews are miles better than plastic wheels on c-beam and lead screws, I bought them from robotdigg
Are you sure about this? Cos I think it is way easier to make round plastic wheels and aluminum profiles with high precision than to make rails and keep them straight while shipping. And even if their precision are the same, price difference is huge. I really should go to dedicated CNC forum to find this out to be honest...

the choice between rails and aluminium with wheels is the choice between cheap and good


I also bought some reasonable nice hgh15 rails on ebay, 2*1500mm + 4 carriages for ~100gbp
This video is why I'm so skeptic about rails:


and if you look at his later videos he is using mgn12 an ballscrews in his latest design


SPI is nice for setting currents and reading errors, but for direction it is a hassle, and it has nothing to do with gcode, it is the
firmware that needs modifications

I never got the stall detection to work on the powerstep01, the datasheet it limited on how should be done (to say the least) and
I'm not even sure it works when not using the internal motiongenerator

Are you saying that powerSTEP01 has issues what comes to programming?  If so than it's a deal breaker, bin there (and partially still am) with other chip whom documentation sucks and even manufacturer support can't help with the matter...

Do TMC5160 have issues/are pain to program as well?


everything complicated is going to be a pain to program, but it the little I've looked at it it seems the documentation on the TMC is better


 

Offline Mechatrommer

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Re: Right motors, PSU for CNC mill
« Reply #35 on: September 22, 2019, 04:22:20 am »
1000 for lathe? Is it made from gold? :D Lathe sized like your 4 axis should cost like 200 buks... I still can't understand why you need lathe on CNC machine, just use your 4 axis and stepper motor to rotate it slowly – let milling bit do the job. If you really want CNC lathe just buy dedicated lathe and add XY axis to it to make it CNC...
the minimum "proper" lathe is something like this... shipping cost for that mini monster can result you in cost of $1000 or more in total... even that mini machine has quirks when reviewed in the net, repairing it requires you to have more bigger lathe/mill cost an arm... anything less than this is a toy imho, even this can be classified as toyish grade... Mini Lathe Machine WM210V Small Household Lathe with 600W Motor secondly it requires large amount of space or extra if you have both of this lathe and cnc separate, esp if you only do some miniaturized devices...


« Last Edit: September 22, 2019, 04:28:33 am by Mechatrommer »
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Online 3dgeo

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Re: Right motors, PSU for CNC mill
« Reply #36 on: September 22, 2019, 04:28:31 am »
the fets on the stepstick are 12A and ~6mOhm apart from the 40V rating much more than that would be pointless
Yep, 40V is a deal breaker, tho I'll probably end up buying both bards for testing their coding.

breaking out the pins take space and even more if they have to go to a reasonable connector
It's a 4 layer board and it looks pretty empty – just admin you were lazy :D

the choice between rails and aluminium with wheels is the choice between cheap and good
Thing is I don't think Cbeams are bad :D Tho I might be wrong...

and if you look at his later videos he is using mgn12 an ballscrews in his latest design
Yes, sadly he did not explained the difference and his reasoning

everything complicated is going to be a pain to program, but it the little I've looked at it it seems the documentation on the TMC is better
I'm not afraid of complexity, I'm afraid poor support/documentation on the matter.

Thank you for your time and answers, now I have to do more digging and make a choice...



Mechatrommer – Google "mini wood lathe" and you'll find what I had in mind.
« Last Edit: September 22, 2019, 04:34:31 am by 3dgeo »
 

Offline Mechatrommer

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Re: Right motors, PSU for CNC mill
« Reply #37 on: September 22, 2019, 04:54:00 am »
Mechatrommer – Google "mini wood lathe" and you'll find what I had in mind.
lathing "wood only" is not what i have in mind.
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