I have noticed that whenever I try to solder a component with many pins close together (like an IC), I get tiny bridges of solder, which shorts the pins. Is there any easy way to solder SMDs without solder bridges?
When soldering by hand, it is easier and faster to just ignore the bridges while you solder the part and then clean it up.
Just put some desoldering wick on the bridge, heat with your soldering iron (may need a bigger tip or more heat) and the excess solder will happily flow into the wick leaving perfect solder joints.
With practice the cleaning of even large parts just takes a few seconds.
There are three golden rules in hand soldering: 1. Use a lot of flux; 2. Use more flux; 3. Use even more flux.
Rosin-based mildly-activated flux (RMA type) helps a lot.
And, of course, right iron power, clean tinned tip, sharp tip (I prefer), and right iron temperature for the solder you are using.
Forget the old soldering iron method.
Solder paste (and a heat gun) is your friend. This method is MUCH easier and faster than soldering each connection!
Assuming you're soldering components on one side of a bare board:
- Put a small (appropriate) quantity of solder paste on each pad; for ICs, you can put a continuous line of paste across all the pads on both sides.
- Carefully place all the SMD components over the paste
- Heat the underside of the board with a heat gun.
All the components will be simultaneously and neatly soldered in seconds, with no solder bridges and much better looking than with an iron!
A video there showing how it's done, but there are much better videos on YouTube.
In addition you should use lot of flux. I would recommend you to try diffrent brands and find the best one for you.
You can also try to use gull wing soldertips. I have one by myself and with the right flux i rarely have to clean up with solder braid. But when i have to, it isn't the end of the world.
In addition to the excellent suggestions already provided. Solder bridges are a fact of life even for the most experienced tech. I find that cleaning the iron tip and then drawing the bridge away in a perpendicular motion to the IC (parallel to the pin/pad) is most effective for me. Oh and regardless of how much flux you use, always clean it afterwards, even the "no clean" flux. Your boards will be much more reliable and long lived.
As pointed out, you can clean that up afterwards. Just be sure to put some solder on the desoldering wick first.
Lead-based solder has much lower melting point so it's easier to work with. That's obviously quite toxic so don't chew on it or leave it where kids have access to it. Solder joints are obviously pretty inert so handling it is ok. The fumes from soldering that normally reach your nose are not dangerous, it's mostly flux. Heavier than air part is the bad stuff so do not use a fan to blow the smoke all over the room.
You would likely benefit from a decent magnifying lamp. 5x lamp makes everything bigger so you can actually see what you're doing. They're not that expensive if you shop around a bit.
Don't touch soldering iron tip with the solder wire. Heat the pin/pad and touch solder wire to another part of the pin/pad.
Besides flux, I'd also recommend using a soldering heat gun for this type of component. Here are some steps you could follow to solder with a heat gun:
- Apply flux on component's pads from PCB.
- Apply tin solder to all pads with soldering iron.
- Apply flux (Again).
- Place component.
- Apply heat with a soldering heat gun (Typically around 15 seconds with 270°C but this depends on the type of tin solder and heat characteristics from the component, which can usually be found on the data sheet).