When Soldering Double Sided PCBs...

[MaltiK]

When I solder components to double sided PCBs, what often happens is, only one side yields continuity. Meaning, I will get my continuity tester/multimeter, and put one probe on one terminal of the Capacitor or whatever, and put the other on the other terminal, and I will see that theyre is no continuity. And then I flip the board over to see that the terminal with the Cap on it, does not have any solder on it, but the other side, the side supposed to have solder, is a good solder joint. Does this happen to anyone else? And am I supposed to put more solder on it so it goes semi through the terminal along the lead of the component? Or do I solder both sides?
Note: this does not apply to SMD components.

I hope that made sense, if not I will take a picture of an example.

[Soeren]

Hi,


It sounds like you are using home made PCB's?

Professionally made double sided boards are allways plated through and only if you drill the hole larger you'll get such an issue.

[Dscrimager]

so, when using boards that aren't plated through or boards that are not double sided is it good practice to use some extra flux to get the solder to flow to the other side through the hole or at least to better coat the connection on the plated side?

I am no soldering expert, but am trying to get better and a few of the boards I have gotten in kits are one-sided and my experience in soldering them is horrible compared to the nice two sided through-plated boards I had been experiencing up to now...

[want2learn]

When making up a double sided pcb and you need to link tracks on opposite sides of the board it is possible to use the leads of through-hole components. I personally don't like doing this.

You can buy things called vias, you just push these in the hole with a little flux then solder them.
Watch though because some via types are meant for heatsinking surfacemount components.

[Dscrimager]

Not to hijack the thread, but where can you buy them I cannot seem to find them....

[want2learn]

I don't know if you're in the U.K. or not so here's a page for someone outside the U.K.

http://www.harwin.com/T1558-T1565/T1564-46-product.html#T1564-46

Select the size you want.

If you use these here's a couple of points:
1. Use a pad with a hole diameter of 0.5mm, if you make the pad hole say 0.8mm for a 0.8mm via you may not get a good contact due to variations in etching

2. Fill all required holes before soldering, solder one side completely then move onto the other.

3. Solder all via's before any other components