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+The most significant challenge in this project is easily the Dreamcast serial
+connector.
+
+As a comparison, Dreamcast "AV connectors" can be purchased at a unit price of
+roughly $1.70 USD on Ebay or $1.00 USD on Aliexpress. These are quality
+connectors that appear to use a copper alloy for the conductive pins. The
+dimensions and fit appear to be reasonably perfect, and the mounting style is
+suitable for direct soldering to a 2.0mm thick PCB.
+
+In contrast, Dreamcast "Serial connectors" only exist either as Sega-original
+parts (and therefore not available in consistent bulk quantities), or in the
+"Dreamcast SD adapter".
+
+I asked many sellers whether they were able to provide the raw connector (not
+yet soldered to a printed circuit board), and in all cases the vendors informed
+me this was not available. The best-advertised price for a complete "Dreamcast
+SD adapter" appears to be about $7.00 USD.
+
+The Dreamcast serial connector from the "Dreamcast SD" product is also vastly
+inferior to the Dreamcast "AV connectors", despite being a very similar
+connector differing only in width and pin count.
+
+At least the following issues exist:
+
+- the outer dimensions of the Dreamcast SD serial connector are too small
+
+- the retaining holes that are intended to "latch" with the female connector's
+  detents are slightly misaligned
+
+- the injection molding is significantly lower quality compared to the Dreamcast
+  AV connector
+
+- the conductive pins appear to be a plated aluminum alloy, a downgrade from the
+  AV connector's copper alloy
+
+Despite this, $7.00 USD is still a decent price. I then investigated the
+viability of salvaging the Dreamcast serial connectors. However, I was
+discouraged when I found desoldering to be too difficult. The issue is a
+combination of:
+
+- the pads on the Dreamcast SD PCB are too narrow (both as a general statement,
+  and as it applies to desoldering specifically), which increases the
+  difficultly of applying copper braid
+
+- a high-temperature solder was used--this means excessive heat is required,
+  which risks deforming the injection-molded plastic
+
+I found the best approach to salvaging "Dreamcast SD connectors" is to instead
+cut the PCB, first separating the Dreamcast serial connector from the bulk of
+the PCB, then cut the PCB between each conductive pin. The pins can then be
+ removed individually, which makes cleaning the pin much easier.
+
+However, all of this considered, I felt that surely it would be easier to just
+make a completely new connector, rather than undertake this scavenging
+process. This would have an additional advantage that already-cleaned connectors
+could be installed at a PCB-assembly factory, no doubt more cleanly, quickly,
+and cheaply than I can do myself.
+
+My original idea was to attempt to directly copy the design of the Dreamcast SD
+adapter's Dreamcast serial connector verbatim.
+
+In my discussions with rapid prototyping factories, the most immediate issue is
+the outer metal shield. This metal shield must fit between a small gap (roughly
+≤0.5mm) inside the female connector. At that size, it effectively means the only
+practical material that could be both the appropriate thickness and
+simultaneously durable would be sheet metal. The Dreamcast SD's serial connector
+uses 0.3mm aluminum sheet metal.
+
+After re-creating a technical diagram for the reverse-engineered dimensions of
+the serial connector's shield, I was correctly informed by rapid prototyping
+factories that this type of sheet metal bending/tolerance requires a mold, and
+the minimum order quantity would be somewhere around 10,000 units.
+
+I don't think I can sell 10,000 units, so the idea seems too risky.
+
+I then redesigned my 3D model to be appropriate for SLM 3D-printing. Compared to
+sheet metal, printed metal is significantly more brittle. To counter this, the
+shield needs to be thickened and reinforced significantly to prevent cracking
+and excessive fragility.
+
+I decided given the overall maximum outer dimensions of the connector, the
+placement and size of the conductive pins, and the consequences this would have
+on the durability of the interior plastic, that the maximum shield thickness
+would would be around 0.7mm.
+
+This thickening has a further compromise, in that 0.7mm will not fit in the
+≤0.5mm gap inside the Dreamcast serial connector. Taking inspiration from the
+RetroOnyx SLS 3d-printed connector, I decided it would be acceptable to remove
+that area of the shield entirely.
+
+After ordering SLM 3d-printed aluminum shields for a fit test, I found the
+results simultaneously impressive and disappointing.
+
+- the outer dimensions, particularly after light sanding, are far superior to
+  the Dreamcast SD connector tolerances
+
+- my slightly-corrected detent-receptacle positioning appears to be perfect; the
+  connector mates with a Dreamcast with a satisfying "snap" feeling.
+
+- I don't know exactly what happened, but during assembly testing at the rapid
+  prototyping factory, the shields were about 0.5mm too long. The factory then
+  corrected this by grinding the parts by hand. This grinding was not done
+  carefully, and many parts are visibly no longer square as a result.
+
+Most importantly, SLM-printed aluminum (and aluminum in general) very strongly
+resists naive attempts to plate it with tin. In my discussions with factories, I
+was surprised to learn that they apparently have never tried to make custom
+connectors like this, and don't formally support any surfacing options that
+would be explicitly usable for soldering.
+
+This causes two problems:
+
+- the solder joint between the PCB and the connector shield is the primary means
+  that the connector is mechanically joined with the PCB
+
+- not being able to provide a solid electrically-conductive path from the ground
+  plane of the PCB and the shield causes the shield to lose some of its "shield"
+  properties.
+
+After thinking about this for many days, I decided that it would be "ok" to join
+the connector to the PCB with a precise application of (non-conductive) glue, if
+I were not able to find a factory able to provide tin-plated 3d-printed aluminum
+(or an equivalent surfacing option that makes the part usable for soldering).
+
+The next issue is in price:
+
+- the factories are able to provide fairly nice laser cut conductive pins, but
+  these are still very expensive: about $1-2 per pin, depending on
+  material/surfacing. I could "save" up to $4 per connector by simply not
+  installing the unused 5V and 3.3V pins, but this feels "too cheap" for me to
+  be comfortable with.
+
+- overall, the material cost for a rapid-prototyped Dreamcast serial connector
+  appears to be around $21 to $31 USD.
+
+I personally think these are quite nice, but I doubt most people think the
+"satisfyingly tactile snap" is worth +$31 USD to the cost of a Dreamcast
+USB-UART adapter.
+
+The next option is to look at higher-volume production. This would mean
+commissioning:
+
+- molds for sheet metal bending for the shield
+
+- molds for injection molding for the pin guides
+
+- cutting stamps for the conductive pins
+
+All of these have minimum order quantities around 1,000-10,000 units. The goal
+would be to get the price of the connector down to somewhere on the order of
+$2-$4/each at 10,000 units.
+
+Is it just me, or is anyone else interested in crowdfunding "a better Dreamcast
+serial connector" into existence?