Where is the fountain of knowledge for learning about CNC setups / understanding them

[Palletlad]

Hi all I have set up my CNC 6040 machine now and have an issue with the motors jamming whilst manually moving them (jams and makes a high pitched noise)
To my understanding this could be my setup of the motors but when I initially got my machine moving yesterday I moved all the motors fine with no issue so not 100% sure.

At the moment I am just copying what others are telling me to put in mach3 settings but I would like to know what I am inputting and why so that I can better understand my machine.
Is there anywhere particular I can look up for research material or download a book etc. and or is there sites to avoid as known for giving incorrect information?

If you are interested my settings on the motors are on the attachment, I am not sure what else you require other than I am using 220v and all three motors have jammed.
PS the temperature in my garage has dropped to 3 degrees I do not know if this makes any difference in the structure/performance of the machine itself.

Kind Regards Graham

[magicniner]

Halve your speeds and try it again, if that works creep them up until you get the occasional issue then back off 15% or so

[Neale]

I'm guessing from the Mach3 settings that you have 5mm lead ballscrews with 8x microstepping in the stepper drivers. That explains the "320 steps per unit" in the motor tuning page. That's about right, but you also need to check the drivers themselves to make sure that they are also set to 8x microstepping to match. If they are set wrongly, you might be trying to move the machine much faster than you expect. The drivers normally have a little table on them showing DIP switch settings.

As long as that's correct, Nick's advice in the previous post is spot on - you can do as much analysis and design as you like, but at the end of the day we all just gradually crank up first speed and then acceleration until the machine starts misbehaving, then back off a bit for safety.

[Neale]

[double post due to network issues]

[Neale]

Is there anywhere particular I can look up for research material or download a book etc.

Try a Google search for "mach3 settings explained". There are plenty of sources of info there, and different people prefer different ways of explaining things, so take a browse through what's on offer.

[Palletlad]

Thanks I will try that my 2 sons wanted to see the machine move so I took them both in the garage and when I clicked the arrow buttons I was sweating thinking oh no the rods aren't properly aligned.

[Palletlad]

oh and Neale this is what I mean you lost me part way through with your explanation so I will research what your referring to, to understand it. my knowledge level on CNC's is beginner at this moment and will try my best to learn it all.

[m_c]

The high pitched noise is the motor stalling.

Stepper motors rely on their windings being energised in order. If you overload the motor mechanically, rather than the motor spinning smoothly, it will stall, and vibrate as it jumps between the activated windings, which is the noise you hear. If you were to feel the motor, you would also feel the vibration. The motor will only start spinning again, once the winding switching speed slows to a point where the rotor can be accelerated fast enough to re-synchronise with the switching.

As others have said, reduce the settings, and try again. There are that many variables involved, that it's hard to accurately calculate readings, so trial and error is the easiest option.
Looking at your figures, I'd reduce max speed to 2m/s, as you may be pushing the limit of what the stepper drivers are reliably capable of.
But I'm confused in your screenshot, because the acceleration figure doesn't match the graph. 300ms2 is very slow for acceleration, yet the graph shows a setting nearer 16'000, which would likely stall even the best of CNC stepper systems.

[Kev2960]

Hi have you tried my mach 3 set-up here
https://the-cnc.blogspot.co.uk/p/home.html?showComment=1516142822415&m=1

[Palletlad]

Thanks guys I will persevere, all your help has saved me from going bald :D
I got the settings originally from https://www.youtube.com/watch?v=0mlfccAVUP4&t=700s was I wrong to trust this then?

[cropwell]

There is a wealth of information here http://www.machsupport.com/help-learning/product-manuals/. The motor tuning section is relevant at this time, but it boils down to winding it up till it fails (stalls) and then pulling back a bit - like wot Nick said. Print out the Installation and Configuration Guide, full of info, but can also help with insomnia:sleeping:

[Kitwn]

One of the key fountains is right here in a sticky thread on stepper motors. Don't try and understand the maths, just use the spreadsheet. In particular note the corner speed at which the motors start to lose torque. Once you get above this speed the torque falls away rapidly.

http://www.mycncuk.com/threads/1524-What-size-stepper-motor-do-I-need

Kit

[A_Camera]

Hi all I have set up my CNC 6040 machine now and have an issue with the motors jamming whilst manually moving them (jams and makes a high pitched noise)
To my understanding this could be my setup of the motors but when I initially got my machine moving yesterday I moved all the motors fine with no issue so not 100% sure.

At the moment I am just copying what others are telling me to put in mach3 settings but I would like to know what I am inputting and why so that I can better understand my machine.
Is there anywhere particular I can look up for research material or download a book etc. and or is there sites to avoid as known for giving incorrect information?

If you are interested my settings on the motors are on the attachment, I am not sure what else you require other than I am using 220v and all three motors have jammed.
PS the temperature in my garage has dropped to 3 degrees I do not know if this makes any difference in the structure/performance of the machine itself.

Kind Regards Graham

The high pitched noise can come from stepper stalling. Try reduce acceleration to half and see if it goes away. Could also be that there are some mechanical issues, so the movement is stopped and because of too low torque, the stepper stalls and you get the high pitch noise. Very difficult to say without more details. The settings you show does not say much about the steppers and the current/voltage you feed the steppers with, or which type of steppers they are. The speed you have configured seems pretty low, but perhaps that's the maximum for your machine, perhaps it can be increased with better drivers and higher voltage.

I have not used Mach3 for quite a while now, but the Internet is full of documentation about how to set it up and which parameter is what. I think Mach3 is THE best documented CNC software in the world, so it should not be difficult to find plenty very well written and detailed pdf documents about it. I know I had a lot of that when I was still using Mach3 and all came from the Internet.

[Kev2960]

Hi, Set your motor tuning to these settings both X and Y 320 1500 400 Z 400 1500 400. You should also go through all the settings on this page;
https://the-cnc.blogspot.co.uk/p/my-mach3-settings.html
These are generally the correct set-up for most 3020, 3040 and 6040. My machine is a 6040 and it took me ages to get it set-up so i started a blog with all the info so that people can just go through and copy the settings. Once the settings are done everything should work ok. If not, then it's probably not the settings and you may need to look at other things, but as I've said this is a good place to start from.
Kev

[Palletlad]

I have done the settings from your blog Kev2960 however I am now recieving external estop requested message appear. what do I look for to amend this?

Cheers

[Kev2960]

hi have you set your control box to manual or pc

[Kev2960]

Have a look at this page how to set the control box

https://the-cnc.blogspot.co.uk/p/control-box.html
and also;

23623

23624 Check the spindle settings

[Palletlad]

erm nope i forgot about that box as hidden away by my feet... I've looked at your vfd video but my vfd is the black box kind which gives me P0,1,3, D1, D2 and d3 which i know know not what to do with.

[Kev2960]

I don't know what settings you need for that box, but there are plenty around, you could try youtube, 6040 black box set-up or some thing similar,

Sorry i can't help but hope you can get it sorted
Kev

[Kev2960]

This is how you set up the black box
https://youtu.be/lncconN83G4

[Palletlad]

ha ha I just finished jotting down the information from this exact video, the guy explains it well unlike the chinazonecnc videos. I will put these details in tomorrow now as I had to go in from the garage pc to the house pc as 1 degrees outside atm.

thank you for your help I will let you know if this solves the "external Estop Request" error message.

Cheers
Graham

[Kev2960]

Morning, I’m sure you’ve checked, but is the emergency stop button on the control box off (twist to turn off and it pops out) sorry I don’t mean to insult your intelligence. Just a thought
Kev

[Palletlad]

Ok I do believe I've messed up the settings on the vfd control box... #sigh
is there a way to reset the settings on the box or do I just go through each setting again and try and put it back to default?
Also I believe I have found someone who has the same box as me and took photos of the innards so I copied the images for you guys to check out and see what I am dealing with, this person also had a UC100 so there thread did not help me.
I am attempting to set up Mach 3 to be able to control the spindle/VFD but am I right in thinking that I cannot do this via a parallel port and instead require a UC100 and Controller card?
I am very tempted to ask if there is anyone that lives near me for a 1 to 1 visit and assistance

23672236732367423675

[cropwell]

~It looks like that board has the facilities to control the spindle with Mach3, but they are not wired in. at the bottom right on pic 4, the board is marked C (Com) NO, which is a spindle relay connection and 0-10v GND, which is the analogue voltage to control speed. I would leave it alone until you have the box working with manual spindle control. Then we can look at the box wiring.

I would not recommend a factory reset on the VFD as you would have a hell of a lot of parameters to sort out. You have probably just taken it off manual control.

[JAZZCNC]

Ok I do believe I've messed up the settings on the vfd control box... #sigh
is there a way to reset the settings on the box or do I just go through each setting again and try and put it back to default?
Also I believe I have found someone who has the same box as me and took photos of the innards so I copied the images for you guys to check out and see what I am dealing with, this person also had a UC100 so there thread did not help me.
I am attempting to set up Mach 3 to be able to control the spindle/VFD but am I right in thinking that I cannot do this via a parallel port and instead require a UC100 and Controller card?
I am very tempted to ask if there is anyone that lives near me for a 1 to 1 visit and assistance

Suggest you take step back from messing and changing settings etc until you know 100% what you have. Just because the box looks the same doesn't mean whats inside is the same. These chinese things are like box of chocolates.? Never know what your going to get.!!

Also, work thru the issues one at a time. Get the machine moving correctly first then move onto VFD etc. With a systematic approach, you'll have it working in no time.

To setup the Motor tuning correctly in mach3 you'll need to know several things.

#1 Ballscrew pitch: To determine this measure how far each axis moves for one revolution of the ball screw. Do this for each axis because very common for Z axis to be different to X & Y.

#2 What micro steps are set on the drives. Most drives have DIP switches that are set in a order depending on what MS you desire. Often the MS setting range is printed on the drives or board. The available choices will be something like 1x 2x 4x 8x or 200,400,800,1600.
If unsure post pictures of your actually board/drives not some one else whcih are the same.

#3 Power supply Voltage and Motor size/Step angle. Two of these are technicly not required but they do give a good indicator for setting Velocity/Acceleration.

To explain the Micro steps ie: 1x 2x 4x 8x: This relates to the Step angle of the motors. So if motors are 1.8deg then this equals 200Steps per Revolution. (360Deg/1.8=200). So 1x 200= 200Ms per rev, 2 x 200=400Ms etc etc.
Now if 200,400,800,1600 etc this says exactly how many Microsteps per rev so easy to workout.

So to calculate the steps Per setting in Mach3 take the MS setting and divide by the ballscrew pitch. IE 800MS / 5mm=160 step per

Now Velocity and acceleration are some what trial and error and dependant on many factors. Motor size, voltage, Friction etc and no two machine will be exactly the same, even if built exactly the same. This is why people just tweak the settings.

However Voltage plays big part in speed/torque that can get from stepper motor so if you only have low voltage PSU Ie: 24V then you'll need to tune Velocity/acceleration much lower than someone with say 48V supply.
This is why knowing the voltage drives use is good indicator regards tuning. 24-36v will struggle much above 2500mm/min so start low and work up.
Also note you cannot have high Velocity and High acceleration, it's one or the other.
So start with both low say 1000 @ 300 then Change one at time and run machine before changing next. Suggest Start with Velocity try it and if motors don't stall then increase acceleration.
Do this several times until find point where changing either one will stall motors. Then back both off 20-25% to give safety margin.

The reason your E-stop isn't working is probably because you have accidentally changed the Input Pin # or Active state.
If your sure E-stop button is working then go to Inputs settings find E-stop setting. First check there is Pin number assigned, if not then thats your problem.
If yes then next toggle the Active Lo setting. Ie If ticked then un-tick vise versa. If mach resets then push the E-stop to make sure it working.

Get this working then we'll look at VFD.

[Palletlad]

ok so I think I did the ballscrew pitch check? I couldn't find a how to do video on it so went along like this, placed ruler 0'd with the drill bit, marked the bolts holding the ballscrew's, 0'd the axis and then inputted a move instruction and stopped the movement when a full rotation of the bolt came round... probably way off what you had in mind.
anyway with this I got the following results:
Y axis moved 5mm with 4.9535 on mach3
x axis moved 5mm with 5.0031
z axis moved 5mm with 3.6062
I took photos of the inside of my control box and you were right its different to the previous photos.
I found the DIP Switches were set on 3 (K3), the X Y and Z axis were also set on SW1.
there is a chart but as its in Chinese I weren't 100% sure what it meant as K3 had a 1 marked in 2 (25%) and 16 (100%)
the motors are 1.8deg
the power is apparently 220 (written on)
please see photos
I tried various settings on the motor tuning ranging from 200, 1000 at 200 to 400. 2000 at 400 I set the step pulse and dir pulse as 0 but all has similar results where there will be a clunking noise once or twice and in worse case on a few of the settings it jams.
at this point I thought could the clunking noise be down to lubrication factor?
Also I have figured out what was causing the EStop so that part is all sorted. 23678236792368023681236822368323684

[JAZZCNC]

Ok, so you have 5mm ball screws.

Now the Sw1 SW2 SW3 set the current range for the drives which must match or be just less than the motors rating. This setting can be set above the motors rating but recommended to keep on or just below.
In your case looks set at 1.8a for all motors even thou the motors are rated 3A. This is a common practice of manufactures when they use these cheap boards. They do it to protect the drives so not working at maximum and overheating.
What this means to you is that you are not getting the full power of the motors. However, it's double edge sword because if you turn them up you'll most likely fry the board unless put some cooling on it.

SW4 it doesn't mention but I suspect it will be to turn motor current reduction on/off. Currently set to ON. What this does is reduce the current to motors when at idle.
The amount of reduction is probably set by K3 K4. Currently set to 50% which is a standard current reduction on drives.

K1 K2 set the Micro stepping which looks to set at 8. Which means 8 x 200=1600 Micro steps.
However, I find it strange jumps from 2 to 8 because usually there's a 4 so can set 800Ms which is a common setting. So I'm not sure I fully believe these markings.
However, it's easy to find out now we know the pitch because the distance traveled will be exactly half or double what we set if wrong.

So start with what it looks to be set at and will take from there. So enter these settings in Motor Tuning.
One note makes sure you select the axis in motor tuning by clicking the axis buttons on the right-hand side when in motor tuning. Also, remember to save before moving to next Axis other wise you'll lose the settings. Also when you input settings into boxs click enter before moving to next box.

Enter these.
Steps per = 320
Velocity = 750
Acceleration = 300
Step pulse =0
Dir =1

These are very safe setting so should work. If you have OK movement but travels wrong distance then probably because switches K1 K2 are not setting MS to what they say they do, which again happens often on Chinese drives like these.

So if traveling wrong distance got 2 options. Change the steps per to exactly half or double 320. If moves half the commanded distance then double the steps and vise versa.

Option #2 let mach 3 do all the work for you by using the SET STEPS PER UNIT feature on the setting tab.(just above Reset)
This will ask you for distance to travel. Then it will travel ask you how far it moved.

So you'll need to mark the table or setup a reference point. Then accurately measure how far it moved. Digital Vernier gauge is good for this.
Can either measure by hand or Open the gauge up full and Zero it then let the machine push it closed.
The large the distance you can measure over the more accurate it will be.

This is good way to quickly set steps per if your unsure. While not always spot it gets you very close.

If machine isn't moving or moving badly then will need a video.

Question what computer are you using. Desktop or laptop.? And what cable.?
If machine isn't moving or moving irraticly then often Parallel cables give troubles so try another cable. It must be Straight-thru or whats called Null Modem cable not an Old printer cable which often cross over the pins.

If using Laptop then that's most likely your problem. Mach3 doesn't work well with laptops unless using motion control card.

[Palletlad]

I'm at work at the moment reading this so will do as you mentioned later on today, I brought a dedicated Pentium 4 pc with XP and Mach3 on it at the moment while using a male to male parallel cable from control box to pc motherboard.
I did a video of me testing random setups with the motor tuning but I will redo it again with your settings.
I let you know the outcome later on tonight.
Thanks for your time with this its helped.

[Palletlad]

ok I did option 2 that's all sorted,

I am still getting the jarring jolts on all various settings so I'm now considering of replacing the wiring with screened wires, greasing the machine all over and buying a UC100 now its payday and looking at new stepper motors.
I found another thread on the web and discovered you was in that one as well Jazzcnc (2014 thread) :D, the guy seemed to have the same issues as me and its looking more like because its cheap parts causing the issues.
I recorded a video and will upload it when I get in to show you what I am getting.

what grease do I get for cnc machines is there a specific/preferred one?
I've found a UC100 on amazon for £53 (its the only one on there) is this trustworthy or a cheap knock off as I thought they are around £130 https://www.amazon.co.uk/Cable-Parallel-Adapter-Converter-Controller/dp/B076P6ZR2L/ref=pd_rhf_se_p_img_1?_encoding=UTF8&psc=1&refRID=V9REG0X8Q9QHK2KA3BGY

[JAZZCNC]

Ok well first don't spend any money on anything because you still don't know what the problem is. Could be anything and throwing money at it without knowing what problem is foolish and sure way to waste money.

The steppers you have will be fine so don't worry about those. Steppers are simple things, they just work or they don't. Provided they are sized correctly for the machine, which these are you won't have any issues with them.
Also just because other folks have had cable issues doesn't mean this is your problem so again leave well alone until you know they are the problem.
Grease doesn't need to be anything special, just normal lithium grease will be fine. However don't go greasing anything yet let us get it working correctly first.

So put up the video and let's see what it's doing.

What you can do thou is going over the machine top to bottom checking no loose bolts or slop in bearings etc. Pay attention to the connection of steppers to ball screws. Check ballscrew end fixing that it's not got any axial movement. Also check Ballnut mountings are tight.

If nothing appears to lose or wrong the next thing you can do is check for any Axis binding. The way to do this disconnects the steppers from ball screws and push each axis thru it's full travel length. They should move quite easily with no binding or tight spots.
Don't be surprised if they don't glide like as if in thin air, this is quite normal and something people often misunderstand.

Only after you know the mechanical is ok should start looking at the electrical. Even then provided nothing is broken you shouldn't need to replace anything just to get motion.
Yes if you want to improve performance then will most likely need to replace some components but should still be able to get good smooth motion using the parallel port and what you have.

So Hold off throwing money at it just yet.

Oh and that isn't UC100 so leave well alone.

[Palletlad]

here is the link to the video
https://youtu.be/fhvOEyyigCM

[cropwell]

This sounds 'mechanical' to me. Does the noise always happen in the same places ?

[JAZZCNC]

It very much sounds mechanical so this is the first place to start.
I would move Y-axis to one side and remove stepper and also remove bolts connecting ballnut to Y axis. Then slide Y axis across gantry to feel if binding on rails.
Then rotate ball nut and ballscrew by hand to see if tight or sticking. Also, check for any axial movement of the ball screw in bearings. Should be none.

If both move freely with no floating in bearings etc then it's most likely an alignment issue with the ball screw.

Also just for reference don't mess around any more with Velocity. Just set it at say 1500 with 500 Acceleration and it should be fine for now. Can always find it's limit when know mechanical is ok.

Also check that you have the Jog percentage set to 100% because some of those movements looked slow.

[Snapper]

These things are made by monkeys. Mine had all sorts of holes misaligned, drilled/tapped at angles etc. I spent a good while stripping it down and straightening it all out, which was a waste of time, because after a bit off cutting the bastard thing just vibrated out of square again.

Anyway, I had precisely the same issue. Mine was down to a crap PSU which eventually set itself on fire. My box was different and had 3 separate drivers, the spindle hooked up etc etc, but a new 48v PSU later and the whole thing was whizzing around without a hitch like a ferret on amphetamines.

[Desertboy]

the whole thing was whizzing around without a hitch like a ferret on amphetamines.
Have you been looking at my new cnc designs ;)

[Palletlad]

https://youtu.be/ROmgTMomsoA here's a small test video of me checking the rails and ballscrew. Note - found almost no grease on anything

[m_c]

Something about the ballscrew/bearings does sound a bit dry, but nothing I'd worry too much about. They don't actually need that much grease, as too much grease can be as bad as too little grease.


Did the parallel port (latency?) test pass OK?
Those clunks could be cause by a glitch in the pulse stream, which is often something causing an interrupt on the computer. I'm going to assume you've done the basics, like ensure all non-essential software has been removed/disabled (that includes any anti-virus).
I'd re-run the parallel port test, and see what results you get. Some hardware configurations are just not suited to running the parallel port for motion control.

[Desertboy]

Something about the ballscrew/bearings does sound a bit dry, but nothing I'd worry too much about. They don't actually need that much grease, as too much grease can be as bad as too little grease.


Did the parallel port (latency?) test pass OK?
Those clunks could be cause by a glitch in the pulse stream, which is often something causing an interrupt on the computer. I'm going to assume you've done the basics, like ensure all non-essential software has been removed/disabled (that includes any anti-virus).
I'd re-run the parallel port test, and see what results you get. Some hardware configurations are just not suited to running the parallel port for motion control.

I have a core i7 running my machine with PP BOB

I had to use on the board graphics as my Nivdia GPU really didn't play well with linuxcnc & turn off hyperthreading then I started to get decent performance, you can also restrict the cores to improve latency.

Multicore and real time are not inclusive terms lol and 20+ years of trying to parallelise to cpu's don't lend themselves to out operation. I've seen more than once people cry out for the good old days of DOS lol.

[Doddy]

Just a quick experiment : Have you tried inhibiting micro-stepping (set micro stepping to 1) on the X/Y, retuning the motors and trying again? Be interesting to see if you're losing steps during the micro-stepping and the clunk is the rapid acceleration of the stepper to catch up on a higher-torque A/B coil step phase.

[Palletlad]

urgh this machine is doing my head in... really tempted to just scrap it all, been trying to find out what the Chinese charts actually mean on the board so I don't damage the board by doing something wrong.
I initially was looking around at breakout boards and their reviews and discovered my breakout board has on board axis drivers as well so if I ever decide to replace it I have to buy stepper drivers as well.
So was looking at the MX3660 which seems perfect (all in one, little hassle) just trying to find a seller and then thought I'm getting distracted again.
I have on the board ("ON DP" K1, K2, K3, K4) accompanied with SW1, SW2 AND SW3 per X Y and Z drivers
K3 and SW1 are the switches set for all three drivers
I found a chart that may assist but still I know too little on this side as all I wanted was to make stuff with the machine.
http://img.yunqudao.com/UploadFolder/4f2543ab-bfc8-48f0-9aff-c49e51612b75/Default/3_649.jpg
is changing K3 to K1 what you mean Doddy to set the micro stepping?
Also I'm going to do a test by taking the motors off of the frame and see if they still make the jarring noise when not attached to the rails, if they still do whilst disconnected then that should eliminate any frame/rail/ball-screw issues I presume and my guess would be either power or a faulty connections somewhere right?
if the motors run smoothly and no jarring when loose then I pretty much scrap the frame? (take hammer to it)
Also (sorry for all the questions) but how can I tell what PSU I have as the only sticker on it was all in Chinese?
PS. the things I have done so far are the following:
brought a standalone dedicated pc with XP and parallel cable for the cnc so no background extras or settings to interfere.
tested multiple settings in Motor Tuning with all having same affect (all three axis jar at least twice and not always in the same area)
tested the rails and alignment also checked the frame was square
have not yet used the machine in any form or had the spindle on whilst testing the motors.
I have not been able to switch the parallel cable with another yet as do not have a spare.
would a UC100 connection solve issues between pc and control box IF it is a communication issue?
(tired now but was trying to think all possibilities)

[cropwell]

I don't know if this has been covered and frankly at 2:30 in the morning I can be arsed to go back over the posts and look. BUT have you checked that the wiring to the stepper motors is solidly connected and that there are no internal breaks in the wiring. Is your machine new or 'pre loved'?

[Doddy]

I have on the board ("ON DP" K1, K2, K3, K4) accompanied with SW1, SW2 AND SW3 per X Y and Z drivers
K3 and SW1 are the switches set for all three drivers
I found a chart that may assist but still I know too little on this side as all I wanted was to make stuff with the machine.
http://img.yunqudao.com/UploadFolder/4f2543ab-bfc8-48f0-9aff-c49e51612b75/Default/3_649.jpg
is changing K3 to K1 what you mean Doddy to set the micro stepping?


A quick bit of clarification, the "ON DP" marking on the DIP switches (the 4-inline blue switches) - the ON represents the position of the "On" state of the switch. So it's not a case that you have K3 on, but rather that you have K1, K2, K4 on. Looking at the markings on the board that represents 8 micro steps. Change one axis (and one only) to Off, Off, Off, Off (all toggles towards the numbers, away from the "ON DP" and retest.

(I'm assuming in the chart on the board that '1' represents a switch in the ON position... not a safe assumption, but the existing settings support that)

Note, that axis will run at 8x the original speed, so you'll have to tune the motor for that axis.

Do this with the motors still hooked up to the machine.

I think removing the steppers from the machine to test... interesting if this does present the problem, but I doubt that it will - the sound is mechanical, and likely related to the stepper performance in situ with the machine. Doesn't mean the machine is toast - just that you have to track down the system, rather than component behaviour... altogether more fun.

[magicniner]

This is probably shutting the stable door......... but, only bugger about with one thing at a time.
I know it's a temptation to change multiple settings on multiple axes in hardware and software at the same time but all that does is confuse you and make it impossible for anyone else to draw any conclusive conclusions.

[A_Camera]

is changing K3 to K1 what you mean Doddy to set the micro stepping?


K1 and K2 is the microstepping. K3 and K4 is the holding current. SW1 - SW3 are the motor current settings. As it is configured in the picture, it is set to 1/8 micro stepping, 50% holding current and 2.5A motor current. Micro stepping means that the total number of steps per rotation (most steppers 200) must be multiplied by the number set by K1 and K2, in your case 8. It means that the driver must receive 8 times as many step pulses as without micro stepping, so 1600 pulses needed for a full 360 degree rotation. It will simply take smaller steps.


all three axis jar at least twice and not always in the same area

I guess you mean "jam"...

Can it be that what you call jam is actually stalling caused by too high speed or acceleration for your machine? Or maybe something mechanical, misalignment for example. Disconnect the motors and try to turn all axes by hand. Is it easy all the way? If not then start with fixing all the mechanical issues first. All screws must rotate pretty easily and most of all, smoothly all the way from one end to the other. If the linear guides are misaligned or twisted then you will have problems, even if you may be able to force your way through using more current.

[m_c]

Going by the picture, K1 and K2 set the microsteps.
K3 and K4 set standby current.
And the SW set motor current.

If the new computer has made no difference, then that should rule that out.

You've got nothing to lose by trying with the motors disconnected from the machine.
What's making me think it's not mechanical, is the seemingly random position the thud occurs, and that it affects more than one axis. If it was something like a bit swarf in a ballnut, I'd expect it to stall completely until the direction is reversed. I'd also expect to be able to feel something moving it by hand. You could perhaps try running the screws with a cordless drill and see if you can feel anything, as something like swarf may only show itself at speed.

However, to me it sounds more like a glitch in the electronics side. My next step would be to try a different power supply, or hook up an oscilloscope to see what was going on.

To answer your previous post, don't get an all in one system. Get a separate BOB, and if funds are really tight, get some of the basic TB6560 stepper drives. They're far from high performance, but they'll match what you've got, and individual drives can be swapped later if needed.

[Palletlad]

I do plan on doing the checks in stages but I thought about seeing if I can prepare a check list and go through it step by step.

I have ordered another db25 cable so going to check the cable.
I am going to grab lithium WD40 spray and give the ball screws and rails a coat.
I am going to test the motors on their own.
If still no luck I will check the board settings as Doddy suggests.
If still no luck then I will purchase PSU I found this one https://www.ebay.co.uk/i/152611070921?chn=ps&adgroupid=49874898239&rlsatarget=pla-398922801293&abcId=1130076&adtype=pla&merchantid=113366689&poi=&googleloc=1006886&device=c&campaignid=1029916224&crdt=0, are these safe to purchase or do i need to go to some specific website to avoid dodgy components?
then go from there by purchacing a bob and stepper drivers as recommended by M_C.
Thanks guys btw for the help thus far and don't panic I am not going to do all and everything in one go.

[Doddy]

However, to me it sounds more like a glitch in the electronics side. My next step would be to try a different power supply, or hook up an oscilloscope to see what was going on.


I tend to agree - but am not convinced yet that this isn't an interaction between the electrical side and the mechanical side. I fear a scope is literally beyond the scope of the investigation so far, and a PSU should show problems simultaneously on jogs on two concurrent axis (and likely exacerbated by such).

OP: Are you familiar with microcontrollers?, I'm thinking in particular I could knock you up an arduino sketch to generate a pulse train to step an axis over a predetermined distance, reverse, etc. Even check out the effects of pulse-width and so on. This would give a health-check on the machine from controller through steppers (including PSU). But for this you'd have to be happy with how to program an arduino and how to connect it to the parallel port interface on the controller (3 wires - ground, step, dir).

[Doddy]

If still no luck then I will purchase PSU I found this one https://www.ebay.co.uk/i/152611070921?chn=ps&adgroupid=49874898239&rlsatarget=pla-398922801293&abcId=1130076&adtype=pla&merchantid=113366689&poi=&googleloc=1006886&device=c&campaignid=1029916224&crdt=0, are these safe to purchase or do i need to go to some specific website to avoid dodgy components?


VM (Max) for a TB6560 is 40V. I'd suggest a 36V PSU.

[Doddy]

I do plan on doing the checks in stages but I thought about seeing if I can prepare a check list and go through it step by step.



Don't forget the cordless drill test on the ballscrew that m_c suggested - it's a good idea.

[m_c]

Just checked, and I should of said get TB6600 drivers if you do replace them.
TB6560 is the older chip, whereas the TB6600 is newer, far more resilient, and has better performance.

Which has also reminded me that the TB6560 has quite a large pulse width requirement. It needs a 10uS minimum pulse width, which limits it to 15KHz step rate. Some where in the Mach settings (think it's the motor tuning screen), there is a box for setting the pulse width. Make sure you have it set long enough.

The attached chart shows the key differences between the chips.

[Doddy]

Just checked, and I should of said get TB6600 drivers if you do replace them.
TB6560 is the older chip, whereas the TB6600 is newer, far more resilient, and has better performance.

Which has also reminded me that the TB6560 has quite a large pulse width requirement. It needs a 10uS minimum pulse width, which limits it to 15KHz step rate. Some where in the Mach settings (think it's the motor tuning screen), there is a box for setting the pulse width. Make sure you have it set long enough.

The attached chart shows the key differences between the chips.

I was about to dismiss this - the controllers I've seen (and modded) have had a 74-series monostable oscillator to pulse-extend the clock signal - however the image of the board (and various clones thereof) don't appear to have this luxury, unless it's rear-mounted on the board? If not, this board is seriously junk. The 10us minimum pulse width is actually dependent on a capacitor value, and can be significantly longer than 10us dependent on value. Mach3 advertises a limit of 1-5us for step/dir pulses, but appears to let you enter a larger value (I can't test as my motion controller is hard-limited to 2.5us). I'd agree - experiment with larger pulse widths (and reducing the micro step to 1 will also help to limit the PRF to a sensible value)

EDIT: My bad - just checked, and the controllers I did modify are TB6600s, not 6560s.

[Palletlad]

Just a quick update, I have confirmed that there is no issue with the frame alignment or ball screw.
I tested the motors when not connected to anything and even on low settings (320,1000,150,0,0)=motor settings.
And they still jam/jar.
so definitely something to do with the electrics/settings.

[Palletlad]

Ooh just remembered to ask I saw the TB6600 stepper motor drivers via amazon and ticked them for a purchase later idea, however when looking for a standard BoB (I know so little on them) I found https://www.ebay.co.uk/i/252085896941?chn=ps&adgroupid=49962971442&rlsatarget=aud-350483661771%3Apla-380178322280&abcId=1129946&adtype=pla&merchantid=107380445&poi=&googleloc=1007060&device=c&campaignid=974960578&crdt=0 and I kept having this one pop up https://www.newfrog.com/product/electronic-parts-for-mach3-cnc-stepping-motor-driver-interface-adapter-breakout-board-with-usb-cable-for-win-xp-system-only-122168?currency=GBP&gclid=Cj0KCQiA2Y_UBRCGARIsALglqQ1eOPANyhoGdRVWpfkf HErmeUFVV7fVsnuYEFqeBEvOjqHOLycyvuwaAsFpEALw_wcB everywhere I looked but not many others? I would have thought there would be all sorts of brands, low, medium, high spec etc

[Clive S]

I would not go with the drives all on one board for the same price you could have :- https://www.ebay.co.uk/itm/5pcs-CNC-Single-Axis-42V-TB6600-2-4-Phase-Hybrid-Stepper-Motor-Driver-Controller/382287002108?_trkparms=aid%3D222007%26algo%3DSIM.M BE%26ao%3D1%26asc%3D20160908110712%26meid%3D648a74 a58db949c9b1a942faa3817bb5%26pid%3D100677%26rk%3D2 %26rkt%3D30%26sd%3D252085896941%26itm%3D3822870021 08&_trksid=p2385738.c100677.m4598

or

3 of these:- https://www.ebay.co.uk/itm/20KHZ-CNC-Single-Axis-TB6600-2-4-Phase-Hybrid-Stepper-Motor-Driver-Controller-Bl/332361372531?_trkparms=aid%3D222007%26algo%3DSIM.M BE%26ao%3D1%26asc%3D20160908110712%26meid%3D648a74 a58db949c9b1a942faa3817bb5%26pid%3D100677%26rk%3D1 1%26rkt%3D30%26sd%3D252085896941%26itm%3D332361372 531&_trksid=p2385738.c100677.m4598

The bob you linked to is OK if you want a cheap one. I have used them a few times

[Doddy]

What's the


low settings (320,1000,150,0,0)=motor settings

part?, have you not tried larger pulse widths on step/direction?

[A_Camera]

Just a quick update, I have confirmed that there is no issue with the frame alignment or ball screw.
I tested the motors when not connected to anything and even on low settings (320,1000,150,0,0)=motor settings.
And they still jam/jar.
so definitely something to do with the electrics/settings.

Good. At least we know that the mechanics are OK. Now change the pulse width to 10. If that doesn't help KEEP it there and change speed to something really low, like 500. If that is still an issue then you probably have a faulty driver card, or a faulty PSU, or both.

I started off with a 3 axis 6560 (blue card). Fixed all the electronic design issues but still managed to fry two before I gave up. In the end I bought a $5 BoB and a handful of DQ542MA drivers and never looked back. My CNC immediately became more quiet, more powerful, faster and with much better acceleration, even though at that time I still had a crappy 24V switched PSU. Changing the driver was the key to success in my case because it solved a lot of issues. That's the route I'd advice you to walk through even if you manage to sort out the current issues. I am still using the same drivers but upgraded the PSU and the CNC in many other ways...

[Palletlad]

Doddy I did attempt with pulses as well but no difference it was the same result what ever setting I attempted.

[Palletlad]

Is this a good BoB? https://www.amazon.co.uk/Motion-Control-Interface-Breakout-Stepper/dp/B076VFT59G/ref=sr_1_7?ie=UTF8&qid=1518697715&sr=8-7&keywords=cnc+breakout+board as I am unsure what I am looking for other than how many axis, connector type (USB/Parallel) would this be a good card to have https://www.amazon.co.uk/gp/product/B0711J1K66/ref=ox_sc_act_image_2?smid=AZ33U9I2AQIQH&psc=1 also https://www.amazon.co.uk/Switching-PSU-S-201-48-48VDC-4-2A/dp/B073QY1614/ref=sr_1_9?s=electronics&ie=UTF8&qid=1518698297&sr=1-9&keywords=psu+48v.
I wont be buying straight away if need be as I still want to check the PSU 1st before any buying but I understand my currant card cant handle a 48v only 36v but is the one I linked good for the above linked items?
Would the setup I have linked be a good idea or are they not a good combination?
Cheers guys for your time.

[Clive S]

Did you not read post #54 as the drive above is very similar and nearly double the price

[Doddy]

Did you not read post #54 as the drive above is very similar and nearly double the price

I think I have 5 of the ones that you linked to sitting in a corner collecting dust... will check tonight and if they are, and my memory serves me correctly, will post a photo or two. There might be justifiable caution to buying from our Chinese friends.

[Palletlad]

Did you not read post #54 as the drive above is very similar and nearly double the price

the only reason I queried that one is because its via amazon so if there was any issues I can replace them via amazon for free under their warranty. I haven't gone through all of them so far as it is its still just a query.

[Doddy]

I think I have 5 of the ones that you linked to sitting in a corner collecting dust... will check tonight and if they are, and my memory serves me correctly, will post a photo or two. There might be justifiable caution to buying from our Chinese friends.

Ah yes, I have a number of these, advertised as TB6600s but which are, in fact, TB67S109AFTG drivers.

23772

Taking one apart...

23773

No TB6600, but on the rear....

23774

A tiny QFN package, pasted to a bit of a heatsink that is then coupled to a secondary heatsink.

After you've been caught once with these, spotting them is pretty easy. For one thing - they advertise a 32 micro step, which isn't supported by the TB6600 (only 16 micro steps).

There's some discussion online that supports these as a reasonable alternative to the TB6600s, but you need to read the data sheets and understand each on their own merits. Personally, I think the thermal solution on these is poor - you could end up with the chip shutting down under load. The R(on) is 20% higher than a 6600 (that's a bad thing that exacerbates the thermal solution). The max clock is 100kHz - doesn't sound bad unless your using 32 micro steps (then it's 100,000 / 32 microsteps / 200 steps/revolution stepper = 15.625 revs/sec, or 937.5RPM max out of the stepper (the 6600 is rated at 200kHz, and only supports 16 micro steps). Lower working voltage and lower drive current (4A vs 5A). Although rated upto 50V worryingly the 67S109 data sheet gives typical characteristics at 24V.

I bought them, and they didn't work well for me (missing steps), but my replacements (TB6600s) also had similar problems that needed the optoisolators updating. I'm not saying they're good, or bad, but different to that advertised.

[A_Camera]

Is this a good BoB? https://www.amazon.co.uk/Motion-Control-Interface-Breakout-Stepper/dp/B076VFT59G/ref=sr_1_7?ie=UTF8&qid=1518697715&sr=8-7&keywords=cnc+breakout+board as I am unsure what I am looking for other than how many axis, connector type (USB/Parallel) would this be a good card to have https://www.amazon.co.uk/gp/product/B0711J1K66/ref=ox_sc_act_image_2?smid=AZ33U9I2AQIQH&psc=1 also https://www.amazon.co.uk/Switching-PSU-S-201-48-48VDC-4-2A/dp/B073QY1614/ref=sr_1_9?s=electronics&ie=UTF8&qid=1518698297&sr=1-9&keywords=psu+48v.
I wont be buying straight away if need be as I still want to check the PSU 1st before any buying but I understand my currant card cant handle a 48v only 36v but is the one I linked good for the above linked items?
Would the setup I have linked be a good idea or are they not a good combination?
Cheers guys for your time.

That's NOT a BoB, it is a complete motion controller. Don't buy it. In my opinion buying drivers based on the Toshiba chip is a mistake. Get the DQ542MA drivers instead, they are miles better. I would also avoid switching PSU. Also, don't be afraid of eBay... there are also plenty sellers with UK (or other EU countries) warehouses with quick shipping. If you have any issues PayPal will give you a refund.