As a certified IPC Trainer the video shows a soldering technique for a practice board to understand the basic technique, although the inspection part was not included at the end. Meaning usually the solder fillets are best inspected when the board is tilted in relation to the microscope to give the best view. You can also use a head mounted magnifier for this large package. Which if you are doing many in production, actually can be faster than using a microscope. The advantage of the microscope that has an attached camera is you can capture an image of the soldered part if this is part of the procedure from the production engineer. For the most part IPC procedures are targeted towards production and production rework rather than repair. This is important because if the task was as seen in the video the PCB lands are usually very clean (new PCB) and without oxidation, so tining the pads before soldering has been omitted. So this video should be seen as an introduction of how to approach the task for contact soldering. However, in actual application SMT power packages are used to convey heat usually through the board with thermal vias (the vias are filled as to not wick solder from the pad), or from the top of the package (IR DirectFET), or into a metal substrate (plate) embedded in the board, and as such are positioned just like any other component in the automated pick and place after application of solder paste. So, are usually not hand soldered in a production setting. For ease of manufacture any required hand soldering is minimized, and relagated to through hole power devices on a heatsink, connectors or temperature sensitive components that are not suited for high reflow temperatures, especially for a lead-free process. I think realistically what you might see in production is if a problem was found in testing that identified an unsuitable power part or perhaps defective or counterfeit parts that then required rework. In this case the procedure would be very different from what is shown in the video. In my experience a preheater is used in conjunction with a hot air station usually running some simple closed loop time-temperature profile to remove the part. Then after the board has cooled a different procedure to solder the new part is used, which would also use preheat and a contact or noncontacting approach depending. In either case the pads are tinned, even after excess solder removal, because of having been used to solder the original part. A mini stencil and solder paste could be used with hot air, or the part could be hand solder using a contact method. In either case the board temp is usully monitored in close proximity to the part being replaced with a thermolcouple. For repair I think a similar procedure would be needed for an SMT power part with a PCB heatsinking approach.
preferred method (compared with another "pro instructor", that heated the drain for 36 sec .. on a lead cushion. nicely done , clean and logical thank you
+stevenv1992 - Hello Steven, my future video releases will have a larger font. You raise a good point. You are correct, it is a wet tack. I very seldom bump a pad unless I am doing chip components. A bump tack preloads the pad prior to component placement.
John Gammell Mr. Gammell, good video, however, you showed the technique with pads that had not been soldered before. When replacing this type of devices and removing as much old solder as possible, would you proceed to solder the component the same way shown here? Thank you, sir.
some times when I solder my hands shakes a little bit but I wanted to be a Repair Man in one Electronics Industry, Now I do it without worry, my hand shakes sometimes hehe. I have seen I am not the only one that hands shakes when soldering Hehe.
Not using IPC-7711/21 procedure? Using external flux in conjunction with flux cored solder wire, are these compatible? Heating the termination leads twice, promoting intermetallic growth. Final result looks in good shape, but we can't judge IPC requirements just by looking at it afterwards.
Yea you can check your solder and flux datasheet to know if it’s compatible or not. Example: using rosin flux core solder with liquid organic Acid water soluble flux, or using Nc flux with water soluble flux core solder. You need to check data sheet.
I need an electronic map for a voltaic regulator for special Russian armor generators so that the input voltage of 24 volts enters the regulator and exits it to the generator. The generator specification is an armature generator with a speed of 1500 cycles and even a minute and an excitator induction coil with a small resistivity of 5 ohms. ) Go to the card can help you in the simplest electronic map
+John Gammell - I'm Mostly interested in the hard stuff, like BGA soldering, fine pitch, etc. Seeing how you solder definitely inspires me to do a better job!
+Haitian Refugee - Proficiency is acquired through repetition. We teach and transfer these skills regularly at Circuit Technology Inc. John Gammell, MIT
If I remember it right: yes it does. Voiding is common with these packages and as far as I know accepted up until a certain percentage of total solder 'fillet' dimension. I'll have to check at work to see if I'm right (yep... DPAK packages are not part of my SMD reworks (yet...)).
+John Gammell This looks really great, but how is it competitive with machines? It seems so slow, do hand soldered boards service a different market than mass produced boards?
Most components are not hand soldered. Hand soldering is for rework and repair, touch up after SMT, prototyping, and some times depending on your application or process certain components are run by hand. Some times boards come back from their end use environment with a latent defect. After test components are swapped to restore functionality. Almost all soldering is done with wave, selective and SMT reflow. I hope this helps.
@@RoadSurferOfficialNope. That's the thing with the vast amount of different solder alloys out there: they all look different to very different after the solder connection has cooled down. To a non-trained eye, leadfree solder connections can look like bad solder joints, while they aren't. The IPC-book at work shows a large table of the 7 (or so) most common or the 7 available solder alloys and how connections look after cooling down, to prevent judging a joint as bad, while it isn't.
