1. Keep component changes to a minimum
When specifying a bill of materials (BOM), it is notuncommon to find a design engineer listing several similar components in thesame board reference. While this selection element may be provided with thebest of intentions, it can be a challenge because the sizes and shapes of partsoffered by different manufacturers may vary.
Surface mount pickup and placement programs aretypically set up for a specific component. Any deviation from the expectedtolerances may result in the part being rejected and the production linestopping grinding. For consistency, always ask your material supplier toschedule only one approved part -- or at the very least, they should let youknow of any possible changes so that your pick and drop program can be updatedoffline 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 packagingmethods can include waffle trays, tubes, and reels -- each usually identifiedby a specific letter or number at the end of the part number.
If your goal is to achieve optimal efficiency, tapeand winding parts are preferred, as the use of tubular parts relies on theoperator to change parts as the tube empties, which can delay the manufacturingprocess. Of course, in some cases, requesting gummed and wound parts may not befeasible, such as in the case of a new product introduction (NPI) with atypically small batch size. In these cases, it may not make business sense topurchase a larger quantity of the device, so you can receive it in both audioand scroll formats.
If you decide to replace the parts from tubularpackaging to tape and reel, you also need to ensure that the sealing quality ofthe cover band is adequate. Poor quality seals increase the risk of cover bandmovement, which can mean that parts can be damaged or lost.
3. Avoid splicing components
In some cases, it may be necessary to splice a smalleramount of tape and a combination of winding components together to form alarger continuous strip. But if this splicing is not performed well, the tapemay get stuck in the surface mount machine. If the cover is pulled away fromthe load belt, you will be left with stuck machines that need to be resolved bythe operator, resulting in costly downtime.
4. Planning isn't always something to plan
Inherent in the manufacturing process is that sometimesthings 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, youmay have two difficult choices. You can choose to continue with the SMT buildand manually fit the part once you arrive, or you can stop working while youorder (and wait) for a replacement part. The reality is that neither option isparticularly ideal. Manual installation of parts can affect quality, increasethe risk of damage, and affect your delivery time. In the meantime, choosing tostop working means your machine is idle and costing you money.
Putting wear and tear into your component kit may costyou a small amount to start with, but it can save you hundreds of pounds inextra rework. So whenever possible, make sure you ask for more of eachcomponent than you actually think. The smallest details can have a huge impacton the efficiency of PCBA production. By having a process in place tocontinuously monitor and improve processes, you will be able to identify andeliminate what isn't working, hold on to quality, and improve profitability.