On 9/17/2022 at 8:40 AM, BruceMcF said:
The thing is, this comes from the plastics production technology at the time. To get uniform look and feel, you'd need to use the same injection molds, and to get uniform color, you'd need to get the plastic produced by the same production process. If color match is important today, we can get it by having cameras that take a picture of the product as it is passing through the line and a robot faulting parts that are out of match, so that the line can be taken down and the color adjusted ... but they didn't have that system available back then.
I worked in the early 2000's on updating the automation a plastic plant making Lexan. While making other plastics may be different, I'd suspect that they are very similar in processing/manufacturing.
Basically the start is to make plastic resin from petrochemicals which results in a powder like material (think like flour) which has a consistent default natural colour - off white. This stage was done in a separate plant on the facility. It was then blown over via a pipe to the extruding plant which was the factory I worked on re-automating. Other chemicals are added for various properties, such as colour following a pre-determined recipe, measured by weight.
All the chemicals in a batch are then mixed in powder form. It then goes into a melting pot together to create something that had the constancy of a thick glue - think like candle wax. This process occurred in basically a heated tube with an auger in it called an extruder. if you've ever used a meat grinder that's what to think of. It comes out hot and gets put into a water bath the cools and sets the strands forming a hard continuous plastic rod. These strands then get chopped up into little pellets, dried and off to storage bins.
Here is where the pellets get checked for colour against a standard. Scrapping it doesn't make sense given the effort and cost of the raw materials. If there is off-product (ie not matching the standards - not the right colour) the batch of pellets are sold to a customer who doesn't require a specific tolerance on a property. Colour doesn't matter if the part isn't going into a piece that isn't visible, or the end customer doesn't care about it. Off-product is sold at a discount, but I assume not at a loss. There were certain regions that were known to want the cheapest product rather than an exact colour (or property.)
In making pellets, the next batch might be of a different colour for a different customer. Rather than shut the extruding line down, attempt to clean the extruder out (if possible) then start up the next batch, the next batch would go in just after the last one. This method saved time and money, but created pellets with"in-between" colour (and other properties) which were off-product but still desirable by some customers. This in-between was sent to a different storage bin, which might have pellets from another transition between batches.
The in-spec coloured pellets are then sold to a customer who uses them to mold whatever they want. I'm assuming that Nintendo had a manufacturer mold the cartridge for them rather than make it themselves, much like they would buy the burnt/masked ROMs from a supplier. If the molder didn't meet Nintendo's colour spec, I assume that Nintendo would not purchase the shipment.
Robot colour quality control is rather expensive and difficult especially with vision systems, or at least in the time I was in the automation field. I worked in several industries over a wide range of manufacturing such as automotive, food processing and pharmaceuticals and only saw a few in my time. The issues with lighting, production speed and other factors made it costly to automate. In the computer assembly plants I worked in humans did the assembly of parts to make a machine. An automated robotic system could be built to do the assembly, but one would have to be making mass amounts of computers for a long period of time for it to be cost effective. With case changes, technology advancements (how many processor form factors have you seen since CPUs came in DIPs?) and other items, the time to design, develop, build and roll out would far exceed the lifespan the resultant product would have. On the other end of the spectrum bottling is a process that automation makes sense given the quantity and consistency of the product. Cans and bottles don't frequently change in size or shape; just the contents. Anyone for an "old" Coke verse "new" Coke flame war?
All of the above may be more than you ever wanted to know, and just vaguely related to retro computing but y
ou did get it for free though ?