1. Keep component changes to a minimum
When specifying a bill of materials (BOM), it is not uncommon to find a design engineer listing several similar components in the same board reference. While this selection element may be provided with the best of intentions, it can be a challenge because the sizes and shapes of parts offered by different manufacturers may vary.
Surface mount pickup and placement programs are typically set up for a specific component. Any deviation from the expected tolerances may result in the part being rejected and the production line stopping grinding. For consistency, always ask your material supplier to schedule only one approved part -- or at the very least, they should let you know of any possible changes so that your pick and drop program can be updated offline and you can avoid any expensive machine downtime.
2. Choose the most efficient packaging
The format of the supplied devices can vary widely -- especially in the case of integrated circuits (ICs). Typical IC packaging methods can include waffle trays, tubes, and reels -- each usually identified by a specific letter or number at the end of the part number.
If your goal is to achieve optimal efficiency, tape and winding parts are preferred, as the use of tubular parts relies on the operator to change parts as the tube empties, which can delay the manufacturing process. Of course, in some cases, requesting gummed and wound parts may not be feasible, such as in the case of a new product introduction (NPI) with a typically small batch size. In these cases, it may not make business sense to purchase a larger quantity of the device, so you can receive it in both audio and scroll formats.
If you decide to replace the parts from tubular packaging to tape and reel, you also need to ensure that the sealing quality of the cover band is adequate. Poor quality seals increase the risk of cover band movement, which can mean that parts can be damaged or lost.
3. Avoid splicing components
In some cases, it may be necessary to splice a smaller amount of tape and a combination of winding components together to form a larger continuous strip. But if this splicing is not performed well, the tape may get stuck in the surface mount machine. If the cover is pulled away from the load belt, you will be left with stuck machines that need to be resolved by the operator, resulting in costly downtime.
4. Planning isn't always something to plan
Inherent in the manufacturing process is that sometimes things don't work out as expected. If a surface mount machine misplaces, drops, or damages a component, and you have no more of that component in stock, you may have two difficult choices. You can choose to continue with the SMT build and manually fit the part once you arrive, or you can stop working while you order (and wait) for a replacement part. The reality is that neither option is particularly ideal. Manual installation of parts can affect quality, increase the risk of damage, and affect your delivery time. In the meantime, choosing to stop working means your machine is idle and costing you money.
Putting wear and tear into your component kit may cost you a small amount to start with, but it can save you hundreds of pounds in extra rework. So whenever possible, make sure you ask for more of each component than you actually think. The smallest details can have a huge impact on the efficiency of PCBA production. By having a process in place to continuously monitor and improve processes, you will be able to identify and eliminate what isn't working, hold on to quality, and improve profitability.
