Set it a little higher around 350 C.
1mm is fine.
Clean the pads on the board with a pencil eraser to remove any oxidation and then clean with alcohol.
Also don't use any metal object to hold the header pins while soldering because it will draw away the heat
I went to my local electronics supplier and they were kind enough to show me how to correct it (and correct one in the process), so my HX711 number 2 now resembles this:
Yet, it seems quite weird to me that the serial now spits seemingly random values
(as a reminder, no load cell is connected to this HX711... )
If I connect the load cell, it goes back to "HX711 reading: 8388607" and doesn't budge whatever force I apply to this [insert vulgar word] sensor from hell
After a few minutes, the HX711 also gets quite hot, so it can't be good.
Everyone seems pretty OK with these, so why the heck does it behave like that with me? is there no mercy for the beginners?
Without anything connected it will, so nothing unusual there.
8388607
That is the max value so it indicates that the data pin is stuck high.
Not good, the board may be damaged.
Did it get hot without the loadcell connected?
I don't think the board gets hot without the loadcell connected to it. What does it mean in your opinion ?
I'm done with this for today (Europe, 17:30, 35°C, time for a fresh glass of wine to honor the concept of the "jeudredi" (jeudi = Thursday, vendredi = Friday) ;) Tomorrow i'll solder a fresh HX711 and give it another go. At some point, I'll solve this, but what a pain ! 
How is your load cell connected? Wrong wiring or shorts perhaps?
You connected it wrong or the loadcell has a short inside or the HX711 board is bad, could be a lot of things.
If you have an ohmmeter/multimeter you can check the load cell. You should see a fixed resistance between any combination of the four wires ( green-white, green-red, white-red etc.). The resistance will depend on the loadcell but is probably somewhere between 350 and 1000 ohms.
If the loadcell is good, I'd try a different HX711 board.
Don't blindly trust some online descriptions. And measure all resistances to be sure sensor is ok.
Yes.
Check between red and black and red and white and green and black and green and white just to make sure there are no short circuits.
If there are no shorts, then I suspect the HX711 board is bad.
I'll check the resistance between each pair tomorrow, but my guess is that the HX711 is toasted
Hi, @le_stan
Now its time for a schematic and images of your project so we can see your component layout.
Thanks... Tom.... 
I have been soldering for 60+ years and I never use flux for this sort of thing.
Some green boards have a manufacturing fault, where the ground plane is missing.
Test for continuity with your DMM between E- and ground on opposite sides of the board.
It should be close to zero Ohms.
Faulty boards are also transparent if you hold a string light behind it.
They can be easily fixed by adding a short wire between E- and GND
So...
Time for some data ;)
--> seems at least consistent, but I'm not entirely sure which pair (red/green or white/black) is the power and which is the signal...
This what the HX711 looks like when exposed to light
E- is the second pin from the bottom on the right side, GND is the first pin from the bottom on the left side
Additional measurements:
When the HX711 is connected to the Arduino, I get
And additional information: The HX711 gets hot even when the load cell is not connected.
I'll now try the "Wawa trick" on one of the HX711 and see what kind of measurements I get
Yes, you definitely have the board with manufacturing defect.
Just solder a ~4cm long wire across the board (bottom side) between E- and GND.
After that you should have 4.25volt between E+ and E-
It's not a trick. This fault is well documented all over the internet.
Can't explain the hot HX711. Shouldn't get hot even before the mod. See what it does after the fix.
The higher resistance pair (input impedance) is for the excitation voltage. So white-black goes to E+ / E-
If it's gets hot without the loadcell then it's bad, use another board but make sure it does not get hot before you connect a loadcell.
Don't be surprised if you find out all are bad.
Great, so I get to go against the wiring instructions provided by the seller... I'll try that with another load cell first ;)
It easy to make a mistake on a website.
If they did not provide a datasheet it's best to make your own measurements.
It's weird how - at some point in a troubleshooting like that - you somehow kind of lose hope. It seems that whatever you do, you'll always end up in the same place
Yet, my load cell (on of the 3 "originals") is now connected to the HX711 (number 5), clamped to my desk and the example from the library reads between 67450 et 67500. If I press on it, it goes down, if I lift it, it goes up...
It's almost like it is working... weird !
Try first without a load cell. Measure the voltage between E+ and E- (4.25V)
And see if the chip gets hot.
If the voltage is Ok and the chip stays cold, only then connect the load cell.
