Makerbot Replicator 2 Repair Question

[Wing Wong]

Hi All,

I recently offered to help the local teacher's resource center to take a look at a donated Makerbot Replicator 2 which wasn't working.

Details about the machine:

• Makerbot Replicator 2 (out of warrantee)
• Firmware 7.5 & 7.6
• Mightyboard Rev H
• 4 pin DIN 24V external power brick.

Brought it home to take a look at and have the following symptoms:

• LCD display fires up, but is flashing.
• Buttons are unresponsive.
• After it starts up, it keeps looping, playing a series of notes.
• If SD card is inserted, the LCD goes dark.
• Printer prints for about 15-20 minutes, then just stops. (RGB LED lights stay lit, USB serial connection dies.)
• Using Makerbot Desktop software and Simplify3D software, I'm able to control the printer and get temp readings.

Recorded a video of it flashing and making the sound, power cycled it, showing it displaying startup and going back into tone cycles. 

https://www.youtube.com/watch?v=NyA-botU3MI  ( sorry for the noise in the video ... -_- )

I checked online and it seems to be either the LCD/keypad control, the ribbon cable, or the Mightyboard itself. 

Things I've tried and results:

• I reflashed the firmware to 7.5 and later 7.6. This doesn't seem to make a difference.
  
• Reseated the various ribbon cable connectors, which allowed me to print for a few hours that night, but the next day, it hung after a few minutes of printing. (going to re-check the cables over the weekend)
• Tried printing with the LCD/Keypad/SDcard module's ribbon cable disconnected, but it makes no difference.

Was wondering if it's just a case of the Rev-H board having failed somewhere, hence the original owner donating it to the school, or if it's something else. 

Ideally, I'd like to be able to give the school some good news that the repairs won't end up requiring replacement parts to be purchased, and they get to a working printer from a dead donated one. 

Ryan was kind enough to give me a rundown of the situation(as well as point me in the direction of this forum) with the Mightyboards: basically, nothing past Rev-E is available, and the various versions out there are either the original flawed Rev-E boards, or a modified Rev-E under a different name. 

I did take a moment to search through these forums for references to the MightyBoard and the LCD issue. Seems like there are a number of possible things that can happen that would have caused a part on the board to have failed. In reference to the thread on broken fan blades, there are 3 blades on the 40mm cooling fan that are broken, causing a bit of vibration. Not sure if it would have ended up causing a component to fail though.

Any help would be appreciated. Worst case, my recommendation back to the school is that they need to get a new board and LCD module, and I spend some time doing the swap. 

Thanks in advance,

Wing.

[Ryan Carlyle]

First thing to check when there are SD card insertion symptoms: is there any debris in the card slot that might be shorting pins together?

Does the school have a working Rep2 that you could try swapping parts with to check what specifically is broken?

[Ryan Carlyle]

Dan or anybody, do you recognize that beep sequence? I don't recall ever hearing it. 

Taking off the rubber cover from the buttons and cleaning out the contacts with some rubbing alcohol may help if you've got a sticking button.

[Dan Newman]

Well, it's not rebooting: if it were, then the splash screen would appear for a few seconds, then the menu,
then repeat (splash screen, menu, splash screen, menu, ...).

The tune doesn't strike me of anything offhand. I suspect it's just an electrical problem
triggering the Piezo speaker. There is an error tune played when a heater is shutdown owing
to a bad error (E5, B4, D4). However, there's also be an error message on the LCD. And the
RGB LEDs would start flashing red.

Dan

[Wing Wong]

Hi All,

Thanks for all of the helpful info/responses. 

Some datapoints:

• The resource center does have another printer, but it's the newer model, the Makerbot Replicator (angular frame).
• If front panel module plugged in during power-on, the repeating tones occurs. 
• If the front panel module is removed after power-on, the tones will continue.
• If the front panel is NOT connected during power-on, the repeating tones will not occur.
• If the front panel is plugged in after power-on, it will not be initialized and repeating tones will not occur.

Some new datapoints:

• Removed the LCD module from the carrier board and the button pcb module from the carrier board. On power-up, it makes the repeating tones.
• Note, there seem to be two chips on the Carrier PCB Rev D ©2012 that have burned out, similar to the issue noted in this thread: https://groups.google.com/forum/#!msg/makerbot-users/p-NM1hsgRz0/ptUN3a2JAwAJ
• Replacement carrier board:  MP03057 from Makerbot ($23.33)
• Gave one of the two chips a light prod and it flaked off like charcoal. :/

Going to try:

• Mightyboard cable re-seat, but leave the LCD ribbon cable disconnected, to see if prints can be completed.
• Alcohol wipe of the pads on the keypad, but at this point, I suspect the issue is burned out chips(literally, they are burned out.)
• Call Makerbot on Monday and see what they have in terms of replacement parts.

Wing.

[Ryan Carlyle]

I'm surprised it works at all with chips burnt out. Not that I have any idea what they do...

[Jetguy]

One is a level shifter.
It takes the 3.3v IO from the SD card itself and converts to 5V signalling used by the atmega1280

The other one is a serial to parallel shift out register.
The LCD data is fed in serial across the ribbon cable, clocked in to hold 8 bits of data, then shifted out 8 bits of parallel data to the parallel character LCD.
Of that, 3 bits are control bits and 4 bits are the actual data. The LCD is in 4 bit mode
 
If say the SD card slot shorted, that could burn up the regulator and OK, maybe fry only the regulator and the level shifter (the 3.3V regulator is fed by the 5V source).

I could see the SD card subsystem damaged by a piece of plastic entering the vertical slot, then bending a finger of the SD card slot in short. That event would have nothing to do with the LCD.

So, going back over the message, I have to think the LCD was working but the SD card system not working.
That in turn means that the 2 items burned are likely the 3.3V regulator and the level shifter.

[Wing Wong]

So, some added data points:

• With the larger of the two burnt out chips removed, the LCD now flashes a bit slower, but the other message it is showing seems to be "NO SD CARD" so I'm guessing yeah, those two chips are critical for the SD card reader.
• I tried a print with the LCD module and it's ribbon cable removed using the Makerbot Desktop software, trying to print the Makerbot screw set, and it stopped after about 10-15 minutes.
• When it's stopped, on the desktop, it indicates that the printer has an error and to go to the Makerbot Support page.
• Please see the <a href='https://www.makerbot.com/support/'>MakerBot Support Page</a> for more information.
• The printer itself is making a sad constant buzzing/ringing sound. I checked the motors and fans and that isn't it. It's like it's coming from the piezo speaker.
• Retry from Simplify3d shows this in the output window:

• WARNING: Firmware unresponsive. Attempting to force continue...

  SENT: d5030a0002d6

I was at 7.6, tried reverting to 7.5.5, but it didn't make any difference.

What's interesting is that I printed three times and each time, the print failed at the same height.

Reprinting with an extra copy of the nut/bolt set on the fourth time, it failed, but at a little less height than the first three times. At this point, I'm kinda leaning towards the Mightyboard board itself might need to be replaced.

Thoughts?

W.

[Jetguy]

entirely possible you have one of a dozen known issues.

You could have had a thermocouple short and that sent 24V down all 5V logic paths.
You could have a failing endstop X axis cable shorting only in a certain position thus resetting the board at a given point.

The thing is, this sounds like an abused and less than cared for machine. There could be a bunch of issues.

[Wing Wong]

@Jetguy, yeah, the more I read up on the issues, the more I think this poor printer has had a rough time of things. 

Which is a shame, since when it is printing, it seems to do a decent job of actually printing. 

I tried printing again and giving each of the endstops' wiring/toggles hits, pulls, and shakes, to see if there might not be something vibration related, but it did not interrupt the print when I did that.  It still locked up at roughly the same height.

So, at this point, in regards to the school's resource center continuing to use this printer in a reasonable manner, it sounds like the only viable option is to replace the Mightyboard and LCD panel with one from say, Flashforge. That would rule out the issue of burned out components or borderline failing components on the board. Though it would require rewiring/etc. due to the different connectors. :/

W.

Wing Wong
winge...@gmail.com
http://about.me/wingtangwong

https://www.facebook.com/wingedpower

[Wing Wong]

Btw, wanted to say thanks to everyone who helped me diagnose and debug this issue. (The group's answers to other folks in different threads were also very helpful in running down issues.)

W.

Wing Wong
winge...@gmail.com
http://about.me/wingtangwong

https://www.facebook.com/wingedpower