Minimum spacing between PCB components

Question

I am laying out a 2-layer PCB that has only through hole components, and I need it to be as small as possible. I was wondering how small I can set the clearance rule between the components?

When I searched I found very dense PCBs that has components nearly very close to one another like this one:

Does any component spacing work as long as pad to pad clearance is nearly 1 mm for easy soldering?

EDIT:

Here is a screenshot of my PCB:

I am leaving very small distance between the fuse holder, pin header and the diode (aprox. 1 mm), is there any thing I need to consider?

Answer 1

Unless you have

• high voltage issues

• crosstalk (by electric fields) between components

• heat dissipation issues

then pack the components as tightly as you are able to insert the thru holes.

You can even have components flush with the PCB, with alternate components raised up a few millimeters, with the solder pads offset as you wish.

And you can hand_form the leads, to be LONGER than usual, to act as very useful jumpers across troublesome traces.

In other words, use the components as a way to have 3 layers or even 4 layers of routing.

Answer 2

Just so you know, that PCB example you posted has very wide spacings.

How closely together you can place traces and components depends is limited by things like how the high voltage and noise. But as far as how close you can physically produce something, this depends on the PCB house you are using. But even a subpar PCB house should be able to accurately produce spacings as small as 0.3mm/12mil, and your typical PCB house will be able to be able to produce spacings much less than this standard.

You should order a PCB ruler from some place like Adafruit, Digikey, or Mouser that has examples of how wide different PCB traces actually are. It gives you a good feel for how things will come out. You will find that a 1mm trace/spacing looks a lot bigger as a trace than it will just looking at the markings on a ruler.