On the other hand, leadless devices — common types include QFNs [quad flat no leads] and LGA [land grid array] package styles — pursue miniaturization through a different route. Ratherthan attach to the board with any extended legs or leads,these devices make contact using solder “bumps” on thebottom of the component package. The place you will mostoften see these types of SMTs will be where very flatstructure heights are required, such as in handheld devicesor where a lot of heat dissipation is necessary. However, the price of this compactness is that both ofthese component types are consequently difficult to placefor hobbyists for single devices when there is no stencilprinting involved. In addition, these packages generallyRoboticists need a plethora of skills to create and construct theirautomatons. Knowing how to solder is a major part of moving fromsimple kits into the realm of advanced circuits and chassis. SERVO 06.2015 63Figure 2. Make sure the apertures of the stencil are properlyaligned on the part. Figure 3. Don't worry if there's a little excess paste on the stencil. It can be easily wiped off with a lint free cloth. Figure 4. If using a brush to apply alcohol, be careful not to scratchFigure 5. Make sure that the apertures are well aligned beforeyou fully stick the stencil down.