Incrementally installing surface mount as parts shipments arrive

RECEIVED 10 OF 15 SHIPMENTS OF PARTS FROM SUPPLIERS

In several cases, the distributor Digikey broke up my order to ship the bulk immediately and then any items that were temporarily unavailable in a slightly later package. One of my Mouser orders is also in the mail. At this point, I know of two additional shipments that should arrive in the next day or two.

There is a package from China, bought from Aliexpress, which is festering in Customs in China since it is the midst of Chinese New Years over there - eight days so far for two connectors. That is likely the last package that will arrive; currently projecting Feb 9 to Feb 16th as the date range but it all depends on customs in two countries plus the third-tier delivery service that actually comes to my door with some shipments from China. 

A single part has not yet been dispatched by Digikey, thus the date of arrival is unknown, so it is a contender for the last package award. Finally I am building a 'catchup' order with Digikey, on eI have not yet issued, where any tiny parts that get lost in assembly will be replaced. 

SORTING AND MARKING PARTS TO EASE ASSEMBLY

I am working with the bill of materials (BOM) for the Main Board to identify the parts that are intended for that assembly. I mark the component designator from the board for the parts on the package. This makes the actual soldering easier, as I just grab bags, take out the parts and solder them on the board according to their names. After each batch of soldering I cross off the parts from the BOM. Conveniently, the BOM indicates parts for the underside of the PCB in red, so I know which side to search for each part's location. 

Parts that don't match the BOM or are surplus to parts I already soldered on will be sorted into three other boxes for later handling. These are hardware, other Main Board, and other board boxes.

All hardware related items including knobs, connectors, switches, transformers and other  non electronic parts go in one box. 

All the through-hole parts I identify for the Main Board from its BOM go in a second box, as these only get installed on the board once I have finished all the small surface mount parts; this preserves easy access for the soldering tip until the surface mount stuff is complete. 

Finally, any other electronic parts are put in the box which is going to be used on either the Front Board or Front Panel. There may be some superfluous parts here as well, but I won't work on marking these bags until I am sure I have finished the Main Board and truly don't need any parts from this box for that assembly. 

PROGRESS ESTIMATE

I have under a hundred components soldered onto the Main Board. The Front Panel has most of the surface mount parts, but not all, soldered on. The Front Board has around twenty parts already installed. 

I might be around 20% complete with the soldering tasks, after which there are physical assembly, checkout and then calibration activities to undertake, so in the grand scheme of the project somewhere just over 10% finished. 

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