Hey. I have switched from the old Pixhawk 6C Mini drone build to “Holybro Kakute H7 wing drone build” as yuri sir and most of you suggested me an year ago that Pixhawk is of no use to me. After that, Holybro sales went off and I was not able to purchase Kakute.
But i have my Kakute now with me, And From now onwards, I will be asking about my build problems in seperate topics*.
I know that in previous long thread of “Inexperienced user support”, You all helped me learn to solder and I did learn. But now, when I was soldering the Kakute H743 Wing pin headers, I really don’t know what is happening, but the tip of my iron (the tip is new and not oxidised, The conical tip shines bright) is not wetting the pins of Headers in this dense area..
Some of the pins do get wet, but in some, the solder refuses to Go into them..
I am not understanding, what mistake am I doing here!? My solder already is a rosin core one. Soldering iron temperature is set to around 320°C. But it feels as if the top of the tip doesn’t heats as much as the Bottom of the tip..
Don’t solder the pins as long as they are inserted into the breadboard. This breadboard takes to much heat away.
What kind of pins you have are this single stripes? If so you can just use the breadboard on one end to fix the strip while you solder the last pin on the other side. If this pin is correct soldered you don’t need the breadboard for the strip as it is fixed by the first pin. Next pin to solder is the first pin on the other end of the strip. And than solder all pins of this strip
As you might know, I am currently soldering that part of the Kakute H743 wing board which consists M9-M14 and the Other Camera, Telemetry pins.
So, It consists of multiple strips there.
But the good thing is that I have soldered at least one pin of each of the strips used here. So the whole pin arrangement can be readily took out of the breadboard.
Let me try after removing this from breadboard and will then report whether things are working or are the same…
You should read thru that thread because every possible aspect of soldering was covered multiple times. From the 1st post about soldering in OCT24 to the last post about soldering in JUN25.
What sizes of conical tip and solder wire you are using? If these are to small it is also contra productive.Is your solder lead-free? Your solder temperature is at the minimum end and for lead-free solder to low.
@mike_tk on such modules and pins I never use extra flux. Just only (good) electronic solder wire
@mike_tk : Yes i even added more extra flux there, although I have a good quality Rosin cored solder wire. But even it didn’t work. It just did nothing except pooling a lot around the place and then it eventually burnt. I had to stop soldering in between and then i cleaned it using IPA.
@dkemxr : For sure sir. I have started scrolling through it So as to revise any advice given before, Which I have forgot…
@Juergen-Fahlbusch : Ok, so i used this particular conical tip for soldering:
I am using a grade 60-40, 18 SWG rosin cored solder wire.
I removed the Kakute from the breadboard and all the pins readily came out easily.
I then fixed it on a soldering Helping hand and then started soldering. But to my surprise! I was applying heat from the back side And adding solder, and the particular pin-in-heat started to go down (Not the full strip went lose, but just that single Metal pin went lose and while the strip was there only, the metal pin started protruding out!)
Although, timely I saw that happening and I save my board By re heating the pad and fixing the pin back in place. I got dangerously scared. I think soldering By keeping in the breadboard is safe for me? ?
As For now, I am practising on this kind of brown board to improve My soldering there on Kakute in that dense area…
Ooh, how long did you heat your pins. If the pins come loose from the strip like that, you’ve overheated them. This will not only damage the pin strip but potentially the circuit board as well.
Also, your soldering tips don’t look very new.
First, practice properly removing pin headers from the perfboard. You won’t damage anything else that way.
To do this, insert the pin header into the board from below and place the pins on a solid, non-flammable board or workbench. The board rests loosely on top of the pins. To ensure proper alignment, place a spacer under the board at another free spot so that it lies parallel to the surface. Then solder only the first pin of a row, followed by the last pin of the row. This allows you to check if the row of pins is properly seated. If necessary, you can further align the pins by briefly heating the two solder joints alternately. Only then should you solder the remaining pins.
Wow sir. Superb advice. Followed it and magic happened!
Also, I would like to say sorry to @mike_tk sir. Because It was really one of the points i was making mess with. Actually, I was adding too much a lot of flux at the site and that’s why it was pooling up. But today while experimenting soldering on those brown boards (perforated boards), I tried applying just adequate amount of flux and Soldering became heaven!
And also, I realised that I was using an indeed thick solder wire of 18 SWG. Too much of solder instantly came on the pin pad even when I touched a little. So, I changed to a 22AWG solder wire + Adequate amount of extra flux adding + around 340°C soldering temperature + Juergen sir’s advice and this magic happened! :
(That’s really a LOT Better than the complete mess I was making till now! And now, I will make sure these points to always follow while soldering pin headers =>
Using just adequate amount of flux to make soldering 10X easier
Avoiding breadboard which sinks away all the heat
Using a thin 22SWG solder wire
Heating the pad and the pin together and The total time of contact should be under 3.5 seconds to avoid damaging board.
..Aa, thats just some burnt flux + oxidised solder coating over the tip. But when reheated and Cleaned using sponge, the tip again shines silver bright.
We have completed the discussion about The pin headers soldering. I have successfully recognised the mistakes and solutions. Now after some practice I will soon solder the Kakute pin headers and Will then proceed to the IMU Temperature calibration in the Ardupilot methodic configurator.
I have already uploaded the latest copter firmware into it and created a new vehicle template in AMC.
I will this time Make it sure that no discussion becomes an argument or goes largely off topic.
We are 3 days and a dozen posts into this topic, and it has focused entirely on your soldering issues, so I re-titled the topic. When you move to a new step and need help, start a new topic with a title that reflects the issue at hand.
Sorry sir, but I want my complete drone build in a single thread, so as to keep the previous points in revise. Please allow me to change the name.
Sir I think you are lacking the starter’s perspective that one of the most difficult tasks of Electronics is soldering. . But now i have a hand at it.
Obviously sir, Do you think of me as a guy, repeating the same mistake again and again in every single thread of mine? Just one chance sir. This time I will make sure the discussion remains in control.
This isn’t about what you want. It’s about what’s best for the community at large. Keeping topics separate and distinct with clear titles does that. I am not the one lacking perspective here.
And frankly, yes, you do have a tendency to repeat mistakes, which makes it appear as if you do not listen, despite that I know you are trying hard.
Sir, While attempting pin header soldering, There are pins in which solder flows easily. But at the same iron temperature, And extra flux also added, there are some pins, which seem to be connected to a PCB ground plane (Copper pour) like structure, and on research, i found that This copper pour acts like a heat sink and takes away all the heat!? Resulting in a cold solder joint. So in such a case, what should I do? I tried raising temperature of iron with chisel tip, to 360°C from normal 345°C, but nothing happens.
Should I go further more? Will such a high temperature be ok for The PCB board? Or is there any trick for such regions?
You can go higher than 400 deg C for a few seconds. In some cases, this may even be desirable as it means higher local temps (faster melting of solder) with insignificant temperature rise elsewhere. So, add flux, touch the tip to the pad and then touch the solder to the pad/tip and it should make a nice joint. Also make sure you clean your tip first if you haven;t done so already
Oh yes “Tip Cleaning” ! That’s one of my other big issue!
My solder has flux core, and when I tin the tip, Then the flux also comes out on the tip and due to the high temp of 340-350°C, The flux keeps burning on again and again (Making the tip dark brown/black). This irritates me a lot. . The tip needs to be cleaned a thousand times just in a small soldering session. It wastes solder too.
For sure sir. I have started scrolling through it So as to revise any advice given before, Which I have forgot…
. But now i have a hand at it.
. The tip needs to be cleaned a thousand times just in a small soldering session. It wastes solder too.