Data needed on Ormerod failures

Hi all

I really need your help, to collect some data, to try and work out what is going on with a spate of recent Duet failures. I am not apportioning blame, and it will not affect the state of any warranty claims. I just need to understand what's going wrong, so we can fix it. This relates to a number of emails I have received recently, but I have also seen in comments in the forum of other, similar problems. Examples of these failures have been cited in this thread [forums.reprap.org] by PhilipTheMobster, tat88 (maybe), robbycar, emmander, TONYR, OttoES and possibly quite a few others, and some who don't post here but have contacted me by email.

The specific failures I'm looking for are usually from a printer that has been running, and printing, already. Typically, the ARM processor gets hot, and then strange behaviour is observed - either locking up, or random USB behaviour. The lock-up may happen first (or just be noticed first). It may kill the ARM processor, making the Duet non-functional. The processor should normally run at around 30 to 40C, cool enough to hold a finger on the chip.

We need to rule out any other possible means of failure - ie short circuits through 12V to 5V/3.3V circuit, or 5V to 3.3V. Most of these are through mis-connections of wires, hitting the proximity board on a bed clip when the heated bed is incorrectly constructed, and other such failures - please don't post these sorts of failures here.

Questions:
What was the last thing the printer was doing before the failure? (eg mid-print/homing axes/turned heater on (more likely to be wiring or board fault)/sat doing nothing)
What happened? (eg USB failure, burnt components, board locked up for a period of time until chip cooled down)
Was there any indication in the logs/Pronterface console? (One email report suggested an M-code command was not recognised)
What specific firmware version are you running? (eg RRP 0.57a, RRP 0.69 duet branch, dc42 0.57x etc.)
Any other relevant information? (eg config.g settings)

Please add a picture of the board if there is any evidence of component failure or poor manufacturing processes. Often the ARM chip will end up with a scorch mark on it, but this is usually when 12V has been shorted through it, and may not be relevant. Connections bridged with solder and solder beads may not be relevant - it's usually clear in these cases that it's a board fault.

I'm looking to try and define if there is any consistency in these failures. It's possible that it's a manufacturing fault, failure of a component, or related to firmware. I just need to know where to start even looking! It's so frustrating for everyone involved, and it has us foxed. So if you've had similar problems, please help.

Ian
RepRapPro tech support

Edited 2 time(s). Last edit at 05/13/2014 08:19AM by droftarts.

Ian, you might also want to ask how many kg of filament the board printed in total, in case the failures are related to the amount of printing done.

You've probably already seen my theory about a possible cause in the 'Fried my Duet' thread. I think transients on mains ground with the USB cable connected may be another cause.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

I fried my duet and i send you the info when i get back from work.

Edit : I sendt you a looong pm Ian, hope this describes my problem, if not dont hesitate to ask for more info.

Regards
Christian Jansen
Norway

Edited 1 time(s). Last edit at 05/22/2014 12:42PM by CJansen.

No real light that I can throw on the issue other than the Ormerod stopped a few times when hitting the end stop on the x axis with the ATX psu shutting down before the demise of the Duet. It may be that the cartridge heater wiring allowed the feed wires to short across the Al block. There are marks from the Z axis threaded rod on the sleeving for the cartridge heater which points to contact and perhaps pushing of the heater further into the Al block.

When the Duet died, the Ormerod drove the Z axis down into the bed and didn't stop. I did not notice any smoke or smell (other than normal PLA smell) but the Atmel ARM chip just got hot when I switched it in again, and the laptop flagged a failed USB device.

New Duet has been installed (thanks to prompt replacement by RepRapPro) and I am up and running again printing a whistle. I've taken extra care with wiring routing round the print head and it doesn't touch anything when the x axis is at the end stop.

Tony

Quote
TONYR
It may be that the cartridge heater wiring allowed the feed wires to short across the Al block. There are marks from the Z axis threaded rod on the sleeving for the cartridge heater which points to contact and perhaps pushing of the heater further into the Al block.

My heat protective sleeving had started to split on one of my heater wires, right around the crimp connector, so I have just replaced it. (I have had my hotend apart more times than I can remember, which is probably the cause more than general wear) My wires come out the opposite side so there was never a danger of hitting the Z rod, but even so I thought it wise to replace it.

I had to buy 5m of the stuff though, so if anyone needs any let me know.

Regards,

Les

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Pointy's Things
Pointy's Blog

Hi Ian, I realise you are mainly concerned with Duet Failures here, but I've just has a near miss with the Power Supply PCB.
The problem being that the screw connectors for the Main Power lines for out going 12V had slackend off on my machine without me noticing.
The ends of the Power Supply cables are burnt, and the heat build up has been enough to warp the top of Power Supply PCB Box.

I was going to start installing an Override switch for my Auto Shutdown system when I noticed it...

A few other people have had this problem in the Past. I class this as a near miss, because the insulation on the wires has started to discolour
due to the heat. I'd suggest every one check that the screws on the connector blocks haven't started to slacken back.

After printing a replacement box I intend to solder the wires directly to the PCB.

Regards,
Kim..

Edited 2 time(s). Last edit at 05/24/2014 03:00PM by KimBrown.

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Please send me a PM if you have suggestions, or problems with Big Blue 360.
I won't see comments in threads, as I move around to much.
Working Link to Big Blue 360 Complete

Hi Ian,

Sorry for my late input.

My first board fail to read temperature properly, temperature always stay at high side, I think around 260+ and 60+. Temperature doesn't change with and without thermistor. Main chip get really hot when turn on, wouldn't able to touch it for a long time. XYZ axis able to move.

Second board, intermittently will fail to turn on, usb not recognise and direct connect to PSU also fail (got no respond from web interface). Main chip do not generate heat when fail to turn on, feel warm when it able to turn on. LED near USB will turn on once it is connected.

Do not hesitate to let me know if there is anything that I can help.




Best regards,
tat88