Diagnosing a faulty 3D printer controller

I killed an A4988 driver years back by slipping with the screwdriver when adjusting the potentiometer, just as you supposed. It shorted out and got hot same as that one. It was on a replaceable module and when I swapped in a new one, I found nothing else had been damaged. I bet you would find the same thing.

Good habit to get into. Always using a plastic tipped tool to fine tune potentiometers. I was using such recently to align the laser trimmers of a CD player.

Andrew Donaldson

Also handy for putting tiny magnets back into encoder wheels.

Big Clive

Yes. The part number is "ceramic tweezers" eBay lowest-price-first. Also very useful for placing tiny magnets into encoder wheels. https://www.ebay.co.uk/sch/i.html?_from=R40&_nkw=ceramic+tweezers+-charcoal&_sacat=0&_sop=15

Big Clive

Yeah, the tiny heatsinks are uninspiring, but they seem common.

Big Clive

Ceramic tweezers, very useful for surface mount components as they don't conduct heat to your fingers and there is no metal to short out or scrape off onto the ceramic parts. In the UK Amazon have them. Popular with the vaping people for fiddling with coils and such. Most seem t be ceramic tips only these days but I also have some fully ceramic ones that are good for RF work.

Tokkan FX

Instructive watching you get that QFN33 off. I assume your tweezers are high temperature - do you have a part number?

Mike Page

I'd like to see you actually fixing it. Maybe a part two?

Bas

I killed my anetA8 board by running 12v through one of the endstop I/O pins. The board still worked but the end stop didn't so I had to replace it.

I'm dubious over the aluminum heater-sinks and I haven't watched the video yet. :p EDIT: BOOM Good one brain -you get a cookie! One can also use some shrink on your screwdriver to protect it.

Michael Thompson

Oh a A8 death trap controller :) They are the ne plus ultra of dodgy. What with their habit of turning into a firey ball of death (yeah I loooove my A8 - it's such a hands on bit of kit).

Rik Kershaw-Moore

I have to use the poor man method - isopropyl alcohol to find hot stuff. Great diagnosis.

Nuts 'n' Proud

I bought three of those A8s because the parts were worth more than the price. I'm still printing with one of them with a lot of upgrades after 6 years. I have started using the Big Tree Tech SKR v1.5 Turbo for higher quality.

That was my first 3D printer, it provided me with lots of fun and frustration 😄

elias