MK3 heatbed question - chip on trace  

RE: MK3 heatbed question - chip on trace

Posted by: @alexander-4

Hey there guys and gals,

So I have been printing with my MK3 for about two years now with few issues at all.  Recently I noticed what looks to be a chip in one of the PCB traces on the heated bed.  It seems to be across about 1/3 to 1/2 of the width of that trace and I am concerned about this resulting in a potential increase in resistance or causing some other severe thermal issue over time.  I have yet to notice any change in function so far.

Should I be concerned about this issue and is there anything I can do to remedy it?

 

Alex

 

 

There is not much you will be able to do. I would seal the cut with heat resistant silicone or something similar

You could check the internal resistance of the heating bed. It should be 3,5 ohms.

MK3-Mini-Widerstaende-Heizungen

RE: MK3 heatbed question - chip on trace

Is it a divot/missing material?   Looks a bit like debris on the surface and coated with a top coat.  If the latter then likely not a problem.  If the former then only time will tell, just gets a bit hotter in the area.

RE: MK3 heatbed question - chip on trace

The coating acts an an insulator.  You ideally should restore that property but you need to do it with something that wont cause a bump in that area (or it will make that bit of your print surface bulge upwards).  I've found that using a thin nail varnish will do the trick.

I would monitor that area over time though to make sure there are no signs of excessive heat in that spot. 

RE: MK3 heatbed question - chip on trace

@agkirk

for example - this silicone has good insulating properties, is heat resistant, can be processed well and has excellent adhesion:

https://www.k2-global.com/de/products/k2-black-silicone-350c-85-g

I have used it several times on the 3D printer, for example to glue the printing plates magnets.

RE: MK3 heatbed question - chip on trace

I am not sure how deep that is.  It is easily palpable, consider filling it with the product Karl suggested.  If not, I have plenty of scratched on one of my beds and it functions well.  

RE: MK3 heatbed question - chip on trace

Use nail lacquer, you can get matt black and build it up in layers if needed. Or a thin UV setting adhesive, I suppose UV nail lacquer could work as well.

The advantage of the UV lacquer is that you can put a drop on, drag a credit card over to remove the excess, wipe away any spread still wet lacquer, then when you are happy, give it a 10 second blast with a UV torch and instant set.

Just found this: https://www.nailpolishdirect.co.uk/led-uv-halo-gel-polish-collection-navy-8ml-n2760-p25964

RE: MK3 heatbed question - chip on trace

If you have a micro applicator A tiny drop of cyanoacrylate will insulate, and if you happen to have some silver epoxy around you could very easily rebuild that trace and insulate with cyanoacrylate. without creating a bump. but if you don't already have it it's probably not worth it.

NM

RE: MK3 heatbed question - chip on trace

True.  MOst epoxy and CA glue will take 110-120 C

RE: MK3 heatbed question - chip on trace

The epoxy I use has a service temperature range of -55 to 150C and is of course more conductive then copper, and the CA's range is -55 to 250C and completely non-conductive. it also halts oxidization.

RE: MK3 heatbed question - chip on trace

@swiss_cheese

I would use JB weld.  It will take much higher temps than most epoxies.  

RE: MK3 heatbed question - chip on trace

@cwbullet

is it conductive?

RE: MK3 heatbed question - chip on trace

@swiss_cheese

JB Weld is not a conductor.  It is an insulation.  I use in in Rockets to insulate against heat and electricity.  

RE: MK3 heatbed question - chip on trace

@cwbullet

I see, just to be clear I was suggesting the use of a Silver epoxy specifically, it's (highly electrically conductive) to rebuild the trace and eliminate any resistance potentially caused by a nick or brake in the trace, and the use of cyanoacrylate to insulate it electrically, and stop oxidization of the circuit.

Anyway, Its just a suggestion.

RE: MK3 heatbed question - chip on trace

@swiss_cheese

Understood, I actually used a little JB weld on my printer on a small gouge with clear tape (to shape it flat).  I pealed off the tape.  It worked and does not effect the heat transmission that I can’t tell.   I would not use it for a larger lesion.