Soldering is the well tried and true method that is used in all of the electronics you are currently using to read this. It's reliable, strong, able to be automated & relatively easy to do once you've had some practice.
If you need to make anything with a component that has a pitch less than 1.5mm - it becomes almost impossible to squeeze out conductive paste without shorting between them. Solder however will re-flow over the pins and will often prevent shorts almost by magic even on the smallest of pitch spacings.
If you have the skill to solder & your substrate is compatible - soldering will always be the best choice. Tutorials on learning how to solder can be found from many websites, some popular ones being: Sparkfun and AdaFruit
- Low resistance - The resistance of a solder connection is often entirely negligible.
- Mechanical Strength - The physical hold of a solder connection is much greater than almost any other component mounting method.
- Re-flow - This is by far the greatest advantage of using solder. Once the solder melts under an iron or hot air, it will preferentially flow only onto metal tracks and component pads. This means that you don't have to be a surgeon to attach a fine pitch component, just squeeze on some solder paste and watch it jump to right where you want it.
- Difficult to Master - Soldering is a technique that often takes lots and lots of practice to get right. The up side is that with the Argentum, it's not a big deal if you ruin your board. You can always print another.
- High Temperature - Soldering requires temperatures often upward of 250C (480F) so it can be dangerous and is not suitable for very young children.
- Toxic Chemicals - Most solder contains lead & even lead free solders contain metals really not great for your system. Additionally fumes from flux inside solder should *not* be inhaled. With proper care of storage, fume extraction and washing your hands after touching solders, the process can be quite safe but without preparation and care it can be damaging to long term health.
List of all substrates compatible with the z-axis tape application method: