The two options for transporting an assembly are finger conveyors and templates. The finger conveyor is more expensive to buy initially, and needs to be set up carefully in order to avoid dropping boards. Maintenance is substantial, in terms of dealing with bent fingers and particularly in removing flux residues from the fingers – after all, these are continually fluxed and then their tips are immersed in molten solder.

The great benefit of a finger conveyor is that it can be arranged as part of an in-line conveyor system, with no need for manual intervention. However, the board is not supported, and larger more flexible boards need some support, for example, with a central wire running along the wave soldering machine.

The template option for carrying a board needs much more operator intervention, since boards need to be secured within the carrier before soldering. Although some adjustable templates are available, for most boards specially-tooled templates will need to be commissioned – for volume production this can be quite expensive. Also, the boards go through the machine and have to be returned to the entrance and re-loaded, and, because the templates are fluxed and immersed in solder, they need to be cleaned fairly frequently.

There are, however, advantages in using the template, particularly with thinner boards, because support can be provided on all four sides. Other advantages of using templates are that having a standard external dimension removes the need to reset the conveyors, and difficult-to-solder assemblies may be positioned at an angle to the template, in order to improve drainage. A final benefit for the template is that it can be arranged only to expose to solder selected areas of the underside of the board.

On this basis, a standard 1.6 mm thick board could be handled either way, but a finger conveyor would probably provide the cheapest alternative. However, for the 0.7 mm thick board, which is likely to be quite flexible, a template would provide much-needed support and stiffening, to prevent the front edge of the board being submerged under the solder wave. The template would also be one solution for an assembly with an number of areas that needed to be screened during soldering. However, this needs to be considered quite carefully, because applying a peelable solder resist might prove a less costly option, one screen for printing being cheaper to buy than multiple templates.