<p>Yes, it should be possible to fix, although you might choose to replace anyway on the basis that the repaired bed might give you concerns about how long it will be before your repair fails.</p>

<p>You will need to carefully remove the protective layer to expose the heating element (assuming you can identify where it is likely to have broken). Then carefully solder across the break (maybe with a short fragment of wire).</p>

<p>After making the repair, you should cover the exposed track. This provides both electrical and thermal insulation. In the absence of any suitable high-temperature paintable covering, you could try using kapton tape.</p>

CC BY-SA 3.0
2016-11-24T11:02:16.437Z
2016-11-24T11:02:16.437Z
Sean Houlihane
<p>What happend was short circuit of course. There is no doubt you overheated HB so copper detached from HB base plate. Because you wrote it doesn't work it means copper tracks are broken.</p>

<p>There is very low chance to fix it. I mean it - near to zero.</p>

<p>What you could do is:</p>

<ol>
<li>Detach HB from arduino</li>
<li>Find a place where track is broken (which needs to uncover it from protective layer)</li>
<li>Connect it with a wire</li>
</ol>

<p>Unfortunately even if you do it and your HB will work (electrically) your fixed HB which won't be flat anymore.</p>

<p>So definitely it's to be thrown away.</p>

<p><strong>[edit]</strong></p>

<p>I just realised you have double power HB, which means your HB has 2 heaters... which gives a bit hope.</p>

<p>take a look here</p>

<p><a href="https://i.sstatic.net/GZMZc.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/GZMZc.jpg" alt="enter image description here"></a></p>

<p><a href="http://reprap.org/mediawiki/images/thumb/6/62/Heated-bed-schematic.png/800px-Heated-bed-schematic.png" rel="nofollow noreferrer">here is schematics</a> which could give you an idea</p>

<p>You could check if your second heater works ok</p>

<p>If yes then you are salvaged! :)</p>

<p><strong>[edit2]</strong>
I really suppose the schematics of HB is more or less like this</p>

<p><a href="https://i.sstatic.net/AS2I1.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/AS2I1.png" alt="enter image description here"></a></p>

<p>So if H1 is broken there is a chance to use H2 connecting pins respectively</p>

CC BY-SA 3.0
2016-04-21T11:30:42.567Z
Isn't that track only for the sensor in the middle?  On the other side of the pcb, at the end of those tracks is the thermistor.
zkent
CC BY-SA 3.0
2016-04-21T15:20:09.997Z
@zkent My understanding of this circuit is that there are 2 heaters. #1 between pin 1 and 2 and second between pin 1 and 3. It means pin 1 is common. One of these heaters is broken so try to use second pair. (pairs are 1-2, 1-3)
darth pixel
CC BY-SA 3.0
2016-04-22T02:11:24.537Z
It will still be flat after the repair if you remount it with the heating tracks on the bottom.  That will also help spread out any localized heat difference from a bypassed section.
Chris Stratton
CC BY-SA 3.0
2016-04-21T05:11:33.050Z
2016-04-21T22:13:20.023Z
2016-04-21T22:13:20.023Z
darth pixel
<p>I was working on my printer when something metallic came into contact with the pcb. I smelled smoke and quickly unplugged the printer. Anyway, this is the result and, of course, the heat bed won't heat. </p>

<p>Can this be salvaged or should I toss it and buy a new one? </p>

<p><a href="https://i.sstatic.net/WhRPu.jpg" rel="noreferrer"><img src="https://i.sstatic.net/WhRPu.jpg" alt="shorted"></a></p>

<p><strong>update</strong> the heat bed was not hot at the time. I had the heat bed unscrewed from the chassis but had forgotten to unplug the printer. I am not exactly sure how it shorted but I think it shorted between the power lead connection and the thermistor. </p>

CC BY-SA 3.0
2016-04-21T14:58:56.640Z
FYI I have already ordered a new one for $20 but I still want to see if I can fix this one for the experience.
zkent
CC BY-SA 3.0
2016-04-21T15:23:21.747Z
Worth noting here that all heaters in a 3D printer are always energized with positive voltage. The ground side is what is switched. So shorting any heater element to ground will cause current to flow, whether or not it's "on."
Ryan Carlyle
CC BY-SA 3.0
2016-04-21T19:35:16.640Z
@RyanCarlyle what is the difference as it's in fact a resistor? According to my knowledge it doesn't matter if you change polarity (checked on Mk2 HB - as same as in the case). The only difference is that LED is lit or not.
darth pixel
CC BY-SA 3.0
2016-04-21T21:20:23.923Z
@darthpixel Doesn't make any functional difference in normal use whether V+ or GND is switched. But it's a big safety difference. The entire heatbed circuit is always energized with respect to ground, so any short to ground at any time with the system powered will cause Bad Things. If you switched V+ instead, the heatbed would be safely grounded and inert when not actively being heated by the controller.
Ryan Carlyle
CC BY-SA 3.0
2016-04-21T22:13:35.913Z
@RyanCarlyle I still don't get how it influence on the case of fixing HB. The problem is not how to do it according to all possible standards but to recognize if it can be fixed (make to heat again). Nevertheless I still suppose there are 2 heaters with common pin1. This asumption is made on the table all HB has painted with (which i linked in my answer). (take a look on my [edit2])
darth pixel
CC BY-SA 3.0
2016-04-22T19:22:05.960Z
@darthpixel Oh, sorry for the confusion, I wasn't trying to say anything about your proposed fix. Just commenting on the question -- the fact that the heatbed was "off" doesn't mean it's de-energized. It's an important safety note for people when working on the printer, cleaning build plates, etc.
Ryan Carlyle
CC BY-SA 3.0
2017-02-26T06:15:47.803Z
This sounds like the precursor to settings ones house on fire ...
MakerModder
CC BY-SA 3.0
2017-02-27T15:50:15.997Z
Hello @zkent, I noticed your question has been up for a while now. Have any of the answers below been able to solve your question? If so, would you mind accepting the appropriate answer. If not, what is missing so that we may help you further? Also, if you have figured it out on your own, you can always answer and accept your own solution. Thank you.
tbm0115
<heated-bed>
Can a short-circuited heat bed be salvaged?
zkent
# Can a short-circuited heat bed be salvaged?

(Asked by: username_0 on 2016-04-21)

I was working on my printer when something metallic came into contact with the pcb. I smelled smoke and quickly unplugged the printer. Anyway, this is the result and, of course, the heat bed won't heat.

Can this be salvaged or should I toss it and buy a new one?

[![shorted](https://i.sstatic.net/WhRPu.jpg)](https://i.sstatic.net/WhRPu.jpg)

**update** the heat bed was not hot at the time. I had the heat bed unscrewed from the chassis but had forgotten to unplug the printer. I am not exactly sure how it shorted but I think it shorted between the power lead connection and the thermistor.

**Tags:** heated-bed
> **Comments:**
> **username_0**: FYI I have already ordered a new one for $20 but I still want to see if I can fix this one for the experience.  
> **username_1**: Worth noting here that all heaters in a 3D printer are always energized with positive voltage. The ground side is what is switched. So shorting any heater element to ground will cause current to flow, whether or not it's "on."  
> **username_2**: @RyanCarlyle what is the difference as it's in fact a resistor? According to my knowledge it doesn't matter if you change polarity (checked on Mk2 HB - as same as in the case). The only difference is that LED is lit or not.  
> **username_1**: @darthpixel Doesn't make any functional difference in normal use whether V+ or GND is switched. But it's a big safety difference. The entire heatbed circuit is always energized with respect to ground, so any short to ground at any time with the system powered will cause Bad Things. If you switched V+ instead, the heatbed would be safely grounded and inert when not actively being heated by the controller.  
> **username_2**: @RyanCarlyle I still don't get how it influence on the case of fixing HB. The problem is not how to do it according to all possible standards but to recognize if it can be fixed (make to heat again). Nevertheless I still suppose there are 2 heaters with common pin1. This asumption is made on the table all HB has painted with (which i linked in my answer). (take a look on my [edit2])  
> **username_1**: @darthpixel Oh, sorry for the confusion, I wasn't trying to say anything about your proposed fix. Just commenting on the question -- the fact that the heatbed was "off" doesn't mean it's de-energized. It's an important safety note for people when working on the printer, cleaning build plates, etc.  
> **username_3**: This sounds like the precursor to settings ones house on fire ...  
> **username_4**: Hello @zkent, I noticed your question has been up for a while now. Have any of the answers below been able to solve your question? If so, would you mind accepting the appropriate answer. If not, what is missing so that we may help you further? Also, if you have figured it out on your own, you can always answer and accept your own solution. Thank you.  

---

## 2 answers

### Answer by username_2 on 2016-04-21. Score: 3 | Accepted answer

What happend was short circuit of course. There is no doubt you overheated HB so copper detached from HB base plate. Because you wrote it doesn't work it means copper tracks are broken.

There is very low chance to fix it. I mean it - near to zero.

What you could do is:

1. Detach HB from arduino
2. Find a place where track is broken (which needs to uncover it from protective layer)
3. Connect it with a wire

Unfortunately even if you do it and your HB will work (electrically) your fixed HB which won't be flat anymore.

So definitely it's to be thrown away.

**[edit]**

I just realised you have double power HB, which means your HB has 2 heaters... which gives a bit hope.

take a look here

[![enter image description here](https://i.sstatic.net/GZMZc.jpg)](https://i.sstatic.net/GZMZc.jpg)

[here is schematics](http://reprap.org/mediawiki/images/thumb/6/62/Heated-bed-schematic.png/800px-Heated-bed-schematic.png) which could give you an idea

You could check if your second heater works ok

If yes then you are salvaged! :)

**[edit2]**
I really suppose the schematics of HB is more or less like this

[![enter image description here](https://i.sstatic.net/AS2I1.png)](https://i.sstatic.net/AS2I1.png)

So if H1 is broken there is a chance to use H2 connecting pins respectively

> **Comments:**
> **username_0**: Isn't that track only for the sensor in the middle?  On the other side of the pcb, at the end of those tracks is the thermistor.  
> **username_2**: @zkent My understanding of this circuit is that there are 2 heaters. #1 between pin 1 and 2 and second between pin 1 and 3. It means pin 1 is common. One of these heaters is broken so try to use second pair. (pairs are 1-2, 1-3)  
> **username_6**: It will still be flat after the repair if you remount it with the heating tracks on the bottom.  That will also help spread out any localized heat difference from a bypassed section.  

---

### Answer by username_5 on 2016-11-24. Score: 1

Yes, it should be possible to fix, although you might choose to replace anyway on the basis that the repaired bed might give you concerns about how long it will be before your repair fails.

You will need to carefully remove the protective layer to expose the heating element (assuming you can identify where it is likely to have broken). Then carefully solder across the break (maybe with a short fragment of wire).

After making the repair, you should cover the exposed track. This provides both electrical and thermal insulation. In the absence of any suitable high-temperature paintable covering, you could try using kapton tape.


---

