AndyUK's Build - 1.2x1.0m Gantry

Why 2 switches on each axis if they are traveling.? The point of having traveling switches is to lower the number of switches.

All you do to use 1 switch is set the same input number for each Limit IE: X Lim (++) = Input 1 and X Lim (- -) = 1. X Home = 1. Then when Switch sees the target at each end it trips Both Limits, It doesn't matter which Limit shows on screen all that matters is that it trips when triggered.
When it's homing it ignores limits and looks for the Switch trigger.

Regards Sloped Target then it's not needed for proximity switches. Just needs to see the metal target, However, it is better if switch passes over the target rather than butting up to it.

Also, you don't need 3 switches on Each X-axis. Only need 3 Switches for Both sides. X2 only needs a Home SW it doesn't need Limits the other side deals with Limits.

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Originally Posted by JAZZCNC

Why 2 switches on each axis if they are traveling.? The point of having traveling switches is to lower the number of switches.

All you do to use 1 switch is set the same input number for each Limit IE: X Lim (++) = Input 1 and X Lim (- -) = 1. X Home = 1. Then when Switch sees the target at each end it trips Both Limits, It doesn't matter which Limit shows on screen all that matters is that it trips when triggered.
When it's homing it ignores limits and looks for the Switch trigger.

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Thanks Jazz, didn't realise you could use the same switch for both limit and home! I can see two advantages to using two switches; it means the limits can form part of the safety circuit, and I'm not sure I like the idea of needing software to guarantee a stop.., and on the off-chance I have a faulty home switch or messed up homing sequence, I'm still protected (which is hopefully the only situation that I'm headed towards the limits blindly).

Clearly needs more of a think :)

Quote:

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Originally Posted by JAZZCNC

Regards Sloped Target then it's not needed for proximity switches. Just needs to see the metal target, However, it is better if switch passes over the target rather than butting up to it.

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Cool that saves some shaping.

Quote:

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Originally Posted by JAZZCNC

Also, you don't need 3 switches on Each X-axis. Only need 3 Switches for Both sides. X2 only needs a Home SW it doesn't need Limits the other side deals with Limits.

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Good catch - clearly not with it yesterday :) That is what I've drawn in the circuit diagram, just wasn't thinking straight when playing with CAD...

Quote:

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Originally Posted by AndyUK

Thanks Jazz, didn't realize you could use the same switch for both limit and home! I can see two advantages to using two switches; it means the limits can form part of the safety circuit, and I'm not sure I like the idea of needing software to guarantee a stop..,

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It depends on how you look at it.? Limits are not really a Safety or E-stop situation, they are a positional error not really an emergency situation.
For instance, the most common limit trip isn't because machines run off on its own accord but rather because you jogged into them or set Work zero too close to limits. In which case the Software will warn you and won't allow when soft limits are turned on. However, having to reset the drives every time you jog into a limit soon becomes a pain and on small machines, this happens a lot when first learning.
Also your not actually relying on software with the UB1 or better controllers because the controller's hardware actually stops the motion and then informs software it's happened.

Spent the day thinking about Jazz's suggestions - decided to listen to wisdom :)

The clincher is that it really simplifies the circuits, and I don't have to now work out how to connect the proximity switches I have (NPN NC) in series - I can now just run each back to the controller and have enough input pins to deal with it.

Leaves me needing 5 proximity switches in total - a Positive X limit, two Negative Xs (one each side, doubling as the X homes), a Y and a Z (each doing triple duty). You can see most of them and their trigger plates highlighted in the diagram below.

Attachment 26718

Quote:

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Originally Posted by AndyUK

Spent the day thinking about Jazz's suggestions - decided to listen to wisdom :)

The clincher is that it really simplifies the circuits, and I don't have to now work out how to connect the proximity switches I have (NPN NC) in series - I can now just run each back to the controller and have enough input pins to deal with it.

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KIS approach works best every time. I've built dozens machines that use this setup without any safety issues. The only time I use separate limits is when using Servo motors because they do just take off when Encoders fail.

So, I've had a very frustrating evening trying to get my EM806s to talk to my computer running the Protuner application.

After about three hours of getting 'unable to connect to drive' messages, trying every version of the software known to man, every pin combination I could think of, and every port setting I could muster, on windows 10, Mac OS, and windows 7, I was having absolutely no luck getting my USB to RS232 FTDI adaptor to work. I finally remembered that the old PC i'm using for the CNC has a physical com port on it, and within two minutes everything is working perfectly.... I suppose it counts as a success if it works eventually right?

Anyhow, all my drives are now programmed with the opposite settings for fault output and enable, which means that the fault output is NC, and the drive is only enabled with a high output signal from the UB1's safety circuit. Therefore, if the Spindle or a single drive faults, the drives remain powered but disabled.

The anally retentive label fairy has also visited; I realised whilst wiring up the lines to the control panel I had the potential for 24 terminal blocks each doing different things with no labels, and although I have diagrams and terminal block numbers.... didn't feel like in a years time I'd remember what the hell each one did. Out came the 3D printer, and I printed some stages which fit over the terminal blocks and allow me to place labels on them. I also printed some blanking plugs for my spare GX20 and GX16 holes on the gland plate.

If you also feel like the fairy needs to visit, I've put the files up on thingiverse.

Attachment 26736 Attachment 26737

Time for the Sunday night update!

Electronics have been relocated to their cabinet - everything in there is wired up and done (... I think...). I'm waiting on a couple more bits for the gland plate which are delaying things somewhat (I can't really solder the connectors on until the gland plate has all the right holes in). Thinking a 300mm deep cabinet may have been slightly overkill, but initially I was very concerned about how far the VFD was sticking out.

I've also sorted out the water coolant tank - rather a nice skip find! I've put my water pump in that bottle, just needs wiring up and re-sealing.

Attachment 26771

Next up - the home/limit switches. I've 3D printed holders for them, and mounted two of the three X switches. I plan to silicon that hole to prevent the cable rubbing with vibration once I'm happy with their locations.

Attachment 26772

And last but not least, I've been working on keeping the wiring on the machine tidy. I 3D printed a set of clips to route the wires from the X Right side across to the wall side of the machine, and plan to use this technique all around. This is one of the clip prototypes:

Attachment 26773

And here they are in action:

Attachment 26774

In order from bottom to top, this is the Motor wire, then the water cooling for the motor, then two limit switches. Quite fond of these :)

In other news, I've managed to find some cable chain for Z and Y from another skip, and will order the X axis cable chain tomorrow. You might also spot that I've added in the holder for the Y axis cable chain.

I'm having trouble finding some U section perspex to act as a finger guard on the X right hand side over the ballscrew - if anyone knows a company or person that might be able to help with a custom extrusion or who can bend this, it would be ace. I'd really like to keep it transparent, but keep little fingers out...

Nice and tidy,good job Andy!

Small Circuit Diagram Updates:

Attachment 27225

I've added an extra control line to the spindle to enable the reverse spindle command. Don't know if I'll ever use it, but may as well wire it up while I'm here. I've also added the Z probe, and control line labels, which will probably only make sense to me, but hey, now its here as a backup for me in years to come!

Planned Spindle Parameters with my setup:

Attachment 27227

These are basically as per the sticky thread, but I've customized the multi-input and FA/FB/FC functions, and chosen other parameters for my setup (and added labels for anyone who can't be bothered to look them up in the manual!!).

Progress otherwise has been generally quite slow having been away for a while...

I've finished the gland plate wiring and soldering, and am now working on the cable chain arrangements before finishing up the GX20 plugs on the motors and spindle. I've rescued some old Igus chain from work, but it didn't have any ends, and they're no longer in production, so I'm 3D printing my own mounts which is taking a few iterations.

With the gland plate finished, that is essentially everything in the cabinet done, so I powered it up for the first time in place the other night to test communications etc (PC is on the other side of the garage, had some fun with evil CAT5 cables, panel mount CAT5 joiners, and a apparently one of my crimpers is dodgy). The airflow through the cabinet sounds proper industrial... :) That was then followed up by the PC's graphics card dying, and ironically a licencing issue with UCCNC exactly like Voicecoil's that magically fixed itself after about an hour... I genuinely have no idea what I changed. Fun week.

Bridgeport time has also been limited, so I have one of my x-axis motor mounts and am hoping to mill the second this weekend. The water-cooling blocks are in and waiting, so I'll try mounting the motors in the steel tubing as per the design and see what burns out first :)

PD 14 and PD15 are too low you will get overvolt or over current trips at higher rpm because it cannot get to commanded speed in 2 second or stop spindle in 1 second so it dumps in a load of volts/current to try get there but cannot possibly do it.

Set PD14=5 PD15=10 for safe settings. Then if your not quite at full RPM before G-code starts moving set an M3 delay in the spindle settings.

Hi All,

So, I thought I had the machine all ready to make its first self-powered movements this evening, however I've stumbled!

I'm pretty sure the problem is that the drives are not enabling, because they worked before I reprogrammed the enable to be active high rather than active low, so one of the things I'll do to test is reprogram a drive enable to be active low again and retest.

I thought I'd throw this out to people to see if you can see where I've gone wrong. The drives are wired as per the EM806 manual (below) and my circuit diagram two posts ago.

Attachment 27264

So, each drive has a line from +24V on the UB1 to ENABLE + on the drive via a 2k ohm resistor. The ENABLE - lines are then commoned, and fed into the OSSD output on the UB1. This is the output of the safety circuit, which I can override with a button (so I know the cause isn't limits etc).

The UB1 manual says this about the outputs:

Attachment 27265

And lists the OSSD as just another output that is controlled by the safety circuit:

Attachment 27266

My thoughts were, that when the output is off (i.e. safety circuit broken), no current can flow through the enable optocoupler, so its a logic low. When the output is on current can flow, logic high, drive enabled.

The drives target 10mA on those optocouplers, so 40mA approximately should be within the 70mA sink of the output.

I know the OSSD output is doing its thing because I can see the LED come on when I press the override.

Have I missed something?

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Originally Posted by AndyUK

My thoughts were, that when the output is off (i.e. safety circuit broken), no current can flow through the enable optocoupler, so its a logic low. When the output is on current can flow, logic high, drive enabled.

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I haven't ploughed my way through the UB1 manual, but in general terms it looks like the internal "switch" in the UB1 shorts the pin to earth (in which case current can flow) or not, in which case no current flows. What might be causing confusion is that when the switch is on, current flows, and the output voltage on the pin is more-or-less at earth potential. When the switch is off, the output pin is high voltage (as the resistor and enable output path on the driver form a pull-up circuit). So is your logic the wrong way round? :Low and high usually refer to the voltage on the pin, not current flow.

Yeah that thought did trouble me too...

I didn't notice the drive working when I wasn't overriding the safety circuit, but it's also possible that in that condition the UB1 won't send the step signals.

I need to dig up some example circuit diagrams where people are switching the enable lines of the AM882 or EM806.

I use EM806 and I switch the enable line. Offhand, though, I can't remember exactly how, but I think it's a direct connection from a relay contact on my safety relay. Too late tonight but I'll try to sort out some info tomorrow. I know that my EM806 are in the default "disconnect to enable" mode as I've never tried to reprogramme them.

Optocouplers work a little like elctromechanical relays: When you apply a voltage across the input terminals the output terminals are connected together. In practice most couplers contain a LED which lights up to turn on an open collector transistor. The most common circuit implementation connects the LED cathode and the emitter of the transistor to ground. Your external circuit will normally include a pull-up resistor between the open collector and the positive supply so the output voltage (the collector of the transistor) is high until pulled low by a positive voltage applied to the anode of the LED. The device therefore acts as an inverter in this configuration.

There is no reason why the collector of the transistor cannot be connected to the positive supply and a pull-DOWN resistor connected between the emmiter and ground. The output is now the emitter and the circuit is non-inverting. As long as the collector is allways positive with respect to the emitter the device will work.

Simillarly the anode of the LED can be connected to the positive rail and the cathode pulled low to turn it on if that suits your circuit voltages.

All clear as mud?

Attachment 27268

The stepper controllers I have used have all deaulted to 'enabled' if the enable input is left unconnected. You could test the rest of the beast's function this way.

Kit

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Originally Posted by Kitwn

All clear as mud?

The stepper controllers I have used have all deaulted to 'enabled' if the enable input is left unconnected. You could test the rest of the beast's function this way.

Kit

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Thanks Kit, I've read through a few times and I think that talley's with my understanding. The problem is, I can't get to the collector or emitter in the drive, and only the collector on the UB1, so I don't have a lot of wiggle room to add pull up or down resistors?

It definitely all worked before reprogramming the drivers, it's just a hassle now everything is in place, but that's the first step.

Are the drives powered up when your trying to enable them.? If so it should work if you have switched the Active state to High in the drive it's self and pulled the Opto high. To test the drives then just reset Active state and disconnect the enable.

Yeah drives have power, and I can see the LEDs on the UB1 flashing to indicate the Step and Dir pulses are sent. Unfortunately I'm away from home for the weekend so testing is delayed!

Have just found this from vrasak himself (post #3) - so perhaps I'm just confusing my logic states as per Neale's suggestion, and really the drives just need to be configured active low. Vrasak refers to the need to switch the fault state, but not the enable, which is suggestive :)

https://www.cnczone.com/forums/uccnc...cnc-forum.html

Andy,

I think you understand a fair bit on the old electronic side. I was casually browsing this thread and one thing is niggling me. Opto isolators typically have a low CTR - usually significantly less than 1, often less than 0.5. That does mean that cascading optos is going to end (eventually, depending on CTR and number of optos in chain) with the latter optos not switching effectively. Really, the opto should be switching a high-z logic device rather than the relatively high current LED input on the successive circuit.

You link a rating of the output at 100mA - that /could/ just be the Ice(max) for the PT in the opto, rather than an actual expected switching current (reading the 4n25 data sheet this is the case).

I'm not suggesting this is your problem, but bear it in mind and measure the switching voltages along the opto-cascade,

You learn something new every day!

A scan of the RS catalogue shows you can get inexpensive devices using Darlington output stages with CTR values as high as 50 and more if you have the luxury of designing the circuit yourself, though they have a higher sturated output voltage. Problem is we're often dealing with couplers already installed in larger devices and cannot choose.

Pull-up/down resistors are often already included in many devices, it being a very bad idea to leave logic inputs to float as the mood takes them. This is how the common "enabled if left unconnected" principle is implemented.

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Originally Posted by Doddy

Andy,

I think you understand a fair bit on the old electronic side. I was casually browsing this thread and one thing is niggling me. Opto isolators typically have a low CTR - usually significantly less than 1, often less than 0.5. That does mean that cascading optos is going to end (eventually, depending on CTR and number of optos in chain) with the latter optos not switching effectively. Really, the opto should be switching a high-z logic device rather than the relatively high current LED input on the successive circuit.

You link a rating of the output at 100mA - that /could/ just be the Ice(max) for the PT in the opto, rather than an actual expected switching current (reading the 4n25 data sheet this is the case).

I'm not suggesting this is your problem, but bear it in mind and measure the switching voltages along the opto-cascade,

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Hi Doddy,

Thanks - that is quite high praise, but I'm still very much stumbling my way around so don't assume too much!

I hadn't really considered the CTRs of the optoisolators, however is this relevant if I'm effectively connecting each drive in parallel with oneanother? My intuition is only really concerned about the fact that I have the Optoisolator from the drive, and then the one in the OSSD output which as I understand is effectively acting as a transistor to ground. Upstream of the drive is merely the current limiting resistors and the +24V rail. My ~40mA came from the sum of 10mA per drive based on the current limiting resistors, and if the CTR<1 then I shouldn't have damaged anything staying under 70mA.

I suspect I've totally missed the point here though :) Please educate me further!

Managed to reprogram one of the drives last night (its a faff now they're in the cab) to be Enable Active low, and instantly was able to get my first self-powered movements on that axis (huzzah!! - I'll post a video once I have all three axis working and this enable issue resolved, because as usual the garage is a tip).

I didn't change the enable wiring, and noticed that the drive was enabled whatever happened (one of the other unconnected drives faulted out which dropped the OSSD output, but it had no effect on the active low drive). Therefore, the problem isn't that I've got my logic states messed up, or at least that's not exclusively the problem.

My next step is to try experimenting with wiring setups to try and get the enable functioning. First I'm going to try Vsarak's two suggestions above, first utilising the 5V rail and another output (schematic B), and second, using a differential connection from a spare axis output (schematic A).

The third step would be to try the NPN connection recommendation in the EM806 manual (which I now realise is effectively what I've been trying to do). The only difference here is that the resistors are placed on the ENABLE - line rather than the ENABLE + line - would that really make a big difference? See attached.

Attachment 27311

Quote:

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Originally Posted by AndyUK

I suspect I've totally missed the point here though :) Please educate me further!

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I'm trying not to mis-direct this thread (tangent?, what tangent...), but to explain my logic....

If I redraw your schematic (lesson #1, "Eagle" is not good for this)

Attachment 27314

and zoom into a bit of text that I torturously added

Attachment 27315

If you /assume/ that the opto-isolator on the UB1 OSSD output has a forward current through the LED (I1) of 10mA (not unreasonable, and likely a design goal). Also, /assume/ the CTR is 0.5 for that device. That means that the switching current (Iossd) would be I1 * CTR = 5mA.

Now, Kirchoff's law says basically that the sum of the currents at a node equals zero. So, if 5mA is flowing into the OSSD input, then the sum of currents through the 4 separate '806 drivers must also equal 5mA. Give them the benefit of the doubt and say that all '806's are created equal, then your forward current through each '806 LED is that 5mA, divided equally by 4, or 1.25mA. Not the 10mA that you believe you have. Then you're at the mercy of the circuit design in the '806 behind the internal opto-isolator. That 1.25mA is multiplied by the local CTR and further diminished. Also, the CTR is impacted by the forward current - it's less at 1.25mA than if driven by 10mA, and so the internal switched voltage swing is further diminished, and may, or may not impact on the performance of the ENA input.

The bit of maths around Vossd is easily verified by yourself - measure the voltage, wrt ground, at the OSSD output when you have a fault condition. If the OSSD output was an ideal switch you'd expect it to be 0V. I expect it to be rather higher (calculated around 20V), based on the less-than-ideal switching behaviour of the opto-isolator (and if I have to correct my auto-correct for opto/onto once more....).

I'm cautious of playing too much behind a calculator - measure the voltage yourself. Reality beats theory any day. The one thing that worries me about my theory is that I would expect the behaviour to be accurately described in the owner's manual of the UB1. And the manual doesn't describe my perceived behaviour - so I could be wrong here.

I've tried to look online for a high-res image of the UB1 for information on the opto-isolator chosen - to no avail. If you can check and advise? It could be an intelligent selection of a device with an unusually high CTR. Pretty sure they are not buffered devices as they look to be 4-pin devices.


EDIT:

Here's an idea. Short the OSSD output to ground (or just the wire from the OSSD output). Either that will work as expected (inhibit each driver) or not. That's a quick way to fault-find the circuit.

Wow thanks for that Doddy, I see what you mean now :)

Attachment 27317
What I think are the optoisolators (4pin IC directly above each output) have 838 written in small font above a larger central "P185". Bottom row is "GB JG".

Also, how the hell did that board get so dusty?

Measured the voltage but wrt 24V not ground (oops). Withe all drives on and connected, OSSD output off (i.e. fault condition drive should be disabled) I get 0V reading (so the OSSD pin is at 24V). With the OSSD output on (drives should enable) I get a reading of 23.3V (so OSSD pin is at 0.7V).

Connected a single drive to 5V and the OSSD pin without resistors, worked perfectly. Enabled and disabled the drive like a champ exactly as expected in both active low enable mode and active high enable mode (enabled in opposite situations obviously). Will try connecting all drives simultaneously next, and I guess worst case will just run them through a spare relay operated by the OSSD pin?

Likely a TLP185 or equivalent. CTR = 100-400%. Your measured voltage is fine and indicates the behaviour should be as you expected. Disregard all my random ramblings about optos.

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Originally Posted by Doddy

Likely a TLP185 or equivalent. CTR = 100-400%. Your measured voltage is fine and indicates the behaviour should be as you expected. Disregard all my random ramblings about optos.

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As someone who likes to design and build the odd circuit of his own, I have found your 'ramblings' extremely informative.

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Originally Posted by Kitwn

I have found your 'ramblings' extremely informative.

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Seconded, this train of thought has more than doubled my knowledge of Optos.

Quote:

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Originally Posted by Doddy

If I redraw your schematic (lesson #1, "Eagle" is not good for this)

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Sorry to side track Andy...

Doddy have a look at Fusion 360, they've been working on updates for the PCB design side more recently, I don't know if schematic support is available as I haven't had time to explore just yet...Autodesk owning Eagle i'm now thinking probably not.

Lee, the work auto desk have done is to integrate the eagle board design together with 3d models of components to post forward into F360 for correlation between electrical and mechanical design. Think of it as a 3D viewer for Eagle, but with obvious advantage for designing the mechanicals around the electrical design.

It’s neat when it works but a complete buggeration from a component library manager POV.

Unfortunately it doesn’t make schematic capture any better (though in fairness autodesk have developed Eagle more in the last couple of years than any of the previous owners)

Sorry!, Andy, thread hijack

Quote:

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Originally Posted by Doddy

Lee, the work auto desk have done is to integrate the eagle board design together with 3d models of components to post forward into F360 for correlation between electrical and mechanical design. Think of it as a 3D viewer for Eagle, but with obvious advantage for designing the mechanicals around the electrical design.

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Apologies, Lee - I think I understand where you was coming from. The latest update from AutoDesk for Fusion360 starts to integrate the functions, including schematic capture, from Eagle into the design editor. This is starting to make sense from the changes to the licensing introduced by AD recently - I'm guessing they're looking for convergence between F360 and Eagle - perhaps into a single product. Not sure I like this, and the integration at this time is a bit clumsy, but I'll hold my breath to see how this develops.

Y and X axis moving, apologies for the poor videography and mouth breathing; there are still no limit switches so I was trying to manually control and stay near the estop whilst filming, took far too much concentration.

The Y is substantially quieter (smaller single screw and better alignment I guess) and here its setup for 10m/min and 500mm/s^2.

The X still needs some alignment attention, here its running at 8m/min and 500mm/s^2. I think it was slightly crooked because at 10m/min something mechanical was slipping causing it to stall. Once a pulley was tightened and the gantry realigned it seems okay at 10m/min but time shall tell.

It's sounding and seeming okay to me, but I have very little experience to compare against, so comments and concerns appreciated.

https://youtu.be/e19MUBl4nDw

Here's a short clip of the slipping I was seeing, after tightening the pulley grubscrew but before realignment:

https://youtu.be/5qFjtBsfzp8

Hi Andy, Well done mate it's coming along nicely. Have you checked the steps per is correct because It doesn't look like it's traveling 8 or 10mtr/min to me, thou it's hard to tell from a video? Just use MDI and tell it to move a distance and check it moved the commanded distance. ie: G0 X100 it should move 100mm. Make sure you Zero the axis first and leave enough space to travel.

Thanks Dean :)

Interesting to know it doesn't look like 10m/min, I'll try measuring the speed. Haven't verified the steps per yet, I'm merely going off the theory. Steppers are 1.8° per step, 8x microstepping, 10mm pitch screw, set to 160 steps per unit, jogging at 100% (although granted I could be using the UCCNC software incorrectly!)

Quote:

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Originally Posted by AndyUK

Thanks Dean :)

Interesting to know it doesn't look like 10m/min, I'll try measuring the speed. Haven't verified the steps per yet, I'm merely going off the theory. Steppers are 1.8° per step, 8x microstepping, 10mm pitch screw, set to 160 steps per unit, jogging at 100% (although granted I could be using the UCCNC software incorrectly!)

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Well that's all correct going by the numbers(provided the MS are correct on drives) so could just be the video but quick measure will verify if it is or not.

Great work well done !
For comparison my Y axis is sweet running like yours, and my dual screw X axis is much noisier. I think it’s because they are longer and there is much more going on.

The slipping in the second video sounds like classic stepper stalling to me. The stepper torque just falls away with speed so if the mechanicals are good then just drop the speed back.

Well done for getting this far it’s a great achievement !

Quote:

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Originally Posted by routercnc

For comparison my Y axis is sweet running like yours, and my dual screw X-axis is much noisier. I think it’s because they are longer and there is much more going on.

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Yep happens on all machines over a certain length and it's a combo of vibrations through the frame and resonance from the screws. You should hear what a 10 x 5 sounds like in comparison. I'm currently just finishing one that's using rotating nuts and the X-axis still sounds much noiser than the Y-axis. I'll do a video when it's fit to be seen, it's still not fully dressed with wires and pipes hanging out everywhere.

Quote:

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Originally Posted by routercnc

The slipping in the second video sounds like classic stepper stalling to me. The stepper torque just falls away with speed so if the mechanicals are good then just drop the speed back.

Well done for getting this far it’s a great achievement !

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Thanks :)

I haven't yet tuned the drivers to the steppers, and I've been a bit conservative with the current through them (the water cooling loop which feeds the spindle and the x motors isn't running yet) as I don't want to let them overheat inside the steel box section. Hopefully I'll be able to hit 10m/min reliably when that's done, otherwise I'll live with 7.5.

Today I got the spindle running and the Z axis moving, both seem okay for first use :) Had to swap the spindle rotation direction, and I'm not sure it's hitting the full speed (the VFD says 200 when the dial is at full range, but that might be because I changed the analogue input range for the UB1 which isn't yet in control). Now time to focus on getting those limit switches working before I smash into something!

Jazz, I also quickly verified the steps per using a pair of digital callipers, and the X axis was spot on at 10mm and 50mm. Y axis was 49.95 on a 50mm move which when considering I don't have ultimate faith in the measurement method I'm happy with for now :)

Also, having some fun finding an appropriate waste board. Being that its out in the unheated and uninsulated detached garage, I need something thats going to be stable.

I've been canvassing local shop fitters / plastics suppliers / kitchen fitters for some Tufnol 1P/13, Phenolic Sheet, or Trespa Athlon. Looking for approximately 20x800x1000mm - any quotes I get back are in the £300ish range which feels quite dear, is that expensive or about right? Does anyone have any recommended suppliers or alternative materials to look at?

Quote:

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Originally Posted by AndyUK

Also, having some fun finding an appropriate waste board. Being that its out in the unheated and uninsulated detached garage, I need something thats going to be stable.

I've been canvassing local shop fitters / plastics suppliers / kitchen fitters for some Tufnol 1P/13, Phenolic Sheet, or Trespa Athlon. Looking for approximately 20x800x1000mm - any quotes I get back are in the £300ish range which feels quite dear, is that expensive or about right? Does anyone have any recommended suppliers or alternative materials to look at?

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You should be able to get a piece of HDPE for a lot less than £300. I've just bought a 10' x 5' x 30mm and it was only £500.

I use these for HDPE and acetal

https://www.directplastics.co.uk/hdpe-sheet