UM2 Heated Bed stopped working mid print - solved

[dkaygee 0]

I have a 2 month old UM2 that has been going downhill slowly. I was at the end of a 4 hour print when one of the belts slipped and the hot end began spilling PLA over the side of the build plate and smashing into the side. I aborted the print and scraped up the PLA. (I am not using any adhesive). When I went to print again, the heated build plate would not heat up. Should I assume it's fried or is there a connection I can check somewhere? I took the electronics cover off, but none of the wires were detached. Neither were any of the wires at the rear of the platform detached. Now I have no heated bed and a cracked plastic bearing block. I submitted a 'support' ticket but have not heard back anything yet. Does anyone have any ideas? I would even settle for installing the parts myself if I knew where to find them.

 

[illuminarti 18]

Well, the relevant connections for the heated bed are the terminal block on the electronics board where the two relatively heavy duty wires are connected, and the same on the heated bed itself.

It might be helpful to remove the heated bed to check the connections there - just unclip and remove the glass plate, then undo the three leveling screws.

Its definitely odd about the smashing into the side thing. Can you post some photos? Did you check if all the pulleys are properly tight?

 

[dkaygee 0]

I removed the heated bed and did not see anything out of place. There are 4 wires plugged directly into a block on the heated bed. The wires appear to be in place and solid. On the other end I'm not quite sure where the heated bed plugs in. I removed the larger of the two plates on the bottom of the machine. I found the board that says 'Ultimaker'. There is another cover on the bottom that is smaller below the ulti-controller where the wire harness from the heated bed appears to terminate. However, I cannot get this plate off to inspect the electronics. I'm not quite sure of how this comes apart and I don't want to make it worse.

The bearing block is definitely cracked down the middle and all the belts feel very tight.

 

[dkaygee 0]

I found the green block where 2 of the heated bed wires attach to the board. One appears to be a dark brown from possible heat.

 

[illuminarti 18]

Yes, it looks like the connection may have been overheating or arcing. The electronics board is held on with 4 screws through the base plate of the printer. You could try removing those in order to pull the electronics board free and inspect the extent of the damage, and/or check whether the screws are properly fastened.

I would also open a support ticket with Ultimaker at support.ultimaker.com

 

[illuminarti 18]

Fabrice, please open a new thread about your issues. You can also open a ticket at support.ultimaker.com.

 

[dkaygee 0]

Yes, it looks like the connection may have been overheating or arcing. The electronics board is held on with 4 screws through the base plate of the printer. You could try removing those in order to pull the electronics board free and inspect the extent of the damage, and/or check whether the screws are properly fastened.

I would also open a support ticket with Ultimaker at support.ultimaker.com

 

Thanks. I have an open ticket. I was hoping to find something obvious. I took the 4 screws out of the board and I can see the two wires are fused together (overheated?). I had to pry them apart. I also see a loose wire that I don't know where it goes. I did not see this before I took the board off. It is a whtie/blue connection. Here is a pic.

http://www.flickr.com/photos/119499626@N06/12953765994/

 

[illuminarti 18]

That white blue connector is unused currently - it's not supposed to be connected to anything.

 

[cor3ys 28]

Dkaygee

My print bed just packed up for the second time and it looks like i have the same issue as you apart from my wires did not weld together, i popped the wire back in and it now works, but i also have the discoloration on the block...

 

[gr5 2,265]

I had to pry them apart.

 

Use a meter to check those wires - check the resistance across them when they aren't plugged into the green block. It should be just a few ohms - somewhere between 2 and 10 ohms. Probably around 5 ohms. If it's more like infinite ohms then your problems is actually probably more on the print bed than here and you should resolder things there.

But more likely you already spotted the problem so just screw the "pryed apart" wires back in tight and see if things are working again. You may have damaged the mosfet that turns the heated bed on and off. If so you will be able to verify that there is no voltage at this damaged green connector. The best fix at that point would be to get a new PCB from Ultimaker.

 

[gr5 2,265]

If you do get a new PCB, get a new black block to replace yours with a big crack in it.

 

[dkaygee 0]

Use a meter to check those wires - check the resistance across them when they aren't plugged into the green block. It should be just a few ohms - somewhere between 2 and 10 ohms. Probably around 5 ohms. If it's more like infinite ohms then your problems is actually probably more on the print bed than here and you should resolder things there.

But more likely you already spotted the problem so just screw the "pryed apart" wires back in tight and see if things are working again. You may have damaged the mosfet that turns the heated bed on and off. If so you will be able to verify that there is no voltage at this damaged green connector. The best fix at that point would be to get a new PCB from Ultimaker.

 

Thanks, working with Support now. We'll see what they decide. I wasn't able to free the wires from PCB. The screws holding these wires down seem to be either overtightened or welded shut. It must have been pretty hot at one point.

 

[dkaygee 0]

Update. It turns out working with Support was quite easy. I sent them a few pics of the damaged parts and received replacements very quickly from DHL. Everything is re-assembled and I've been printing again the past few days with no issues.