Damaged heat bed  

RE: Damaged heat bed

If it were mine, I would replace the heatbed.

It's difficult to tell from the photo exactly how badly the surface of the heatbed has been damaged, but it looks like it's down to the bare copper tracings of the heating element.

It may still be usable, since the bottom surface of any PEI build plate is non-conductive, but my question is along the line of the heater being damaged enough to have an 'open' in there, resulting in no heat or inconsistent heat on one or more parts of the plate.

RE: Damaged heat bed

Thanks for your reply jsw. 

I'm going to try painting on a layer of nail varnish and if that doesn't work then I'll have to buy a new bed. Printer is only a couple of weeks old. I could cry. 

Is there risk in trying to print with it damaged ? Like could it short and damage something else? 

RE: Damaged heat bed

I think this heat bed is permanently damaged and won't heat anymore -at least on photo, it seems that copper traces are broken.

RE: Damaged heat bed

If this were mine, I would test the heating capability by simply preheating to 60C or so and either carefully feeling for heat across the bed or using a digital thermometer to sample points across the bed surface.

If there are cold spots, it's time for a replacement.

RE:

2 posibilities for you:

1) I would clean it with Isopropanol and after that I would glue Kapton tape on the whole surface of the heatbed - best would be a complete sheet of Kapton - search the internet and you will find it. It ist isolating (electricity) and can handle the temperatures of the heatbed with ease. That would be my way. I am sure that that will work.

2) Buy a new one (it is always worth to have spare parts!)

Best regards, Clemens

RE: Damaged heat bed

Thanks Bodgan. 

It's actually only just exposed the copper in one area. 

With the layer of varnish the entire heatbed is heating up. 

But I then got a watchdog reset when trying to run a self test. 

Any thoughts gratefully received. 

RE: Damaged heat bed

What was going on during self test when you received the watchdog reset - during heating of the heatbed or what?

Best regards, Clemens

NOT nail varnish, uness you are very sure of the chemistry you may be applying something that turns into glue when hot.

Have you got a multimeter?  Temporarily unplug the heatbed and check the resistance.  If the circuit is open than you have ruined the part but IF there is a resistance, it will be low, it may still be useable, so: Try heating the plate, you are risking popping a fuse but there is a good chance it will still work.

To reinstate insulation you might use a thin layer of radiator or stove paint.

Cheerio,

RE: Damaged heat bed

@ Diem:

Resistance check I am sure will not work. As the Mini heatbed is in principle similar to that of the MK2.5 you have lots of parallel circuits. If one is open (broken) you will not detect it this way.

Best regards, Clemens

RE: Damaged heat bed

Well, a new heat bed is $70. Not the cheapest part but affordable enough. I wouldn't be penny wise and pound foolish and try to futz around with a broken heat bed and create hazards. Write it off as a learning experience and don't start your printing experience with the Mini with a half-assed repair job that may cause more problems downstream and may make issues if they arise harder to troubleshoot. A mistake was made, pay the price, and move on.

Fair comment @clemens-m, and @fuchsr's thoughts are sound too.  I didn't intended to misdirect the OP.

Cheerio,

RE: Damaged heat bed

There are always different opinions and that is good. So the person asking for help gets more than one opportunities and can decide. I am a person who loves to repair and get most out of it. Others like to have parts where they know that they are 100% ok. So no problem to me. There is not the only one right way to go.

Best regards, Clemens

RE: Damaged heat bed

Thank you all. I really appreciate it. 

It seems to working fine now after the layer of varnish. 

The Watchdog Reset happened when I tried to run a self test so I buried my head in the sand and just didn't do that again 🙈 and its printing fine. 

I'm going to order a new bed anyway as I'm worried that it may still short something. 

Completely gutted as it's only 2 weeks old and I'm ashamed to say I'm not quite a novice. I have 3 Prusas and 2 Enders but have never been so dumb-ass as to do something like this before. 

Again, thanks all for your advice. 

(I have another problem with another printer so will probably be posting again tomorrow so thanks in advance if you are around for that! 😂) 

RE: Damaged heat bed

As long as the copper tracks are not damaged, I would cover the print bed with Kapton foil (no varnish layer). I have also carried out various repairs with Kapton.

It's worth a try.

wbr,

Karl