After lurking in the Cthulu thread on SRK for a while, and seeing countless people have issues with wiring. I've decided to create a solution for many people who have a Madcatz Fightstick xbox 360 TE (and SE). This should serve as a two fold operation, it will help those who are terrified of soldering ease into the modding scene, by allowing things like the popular dual mod to require very few solder joints, or possibly none at all. This will also allow those who are familiar with soldering, but don't want to risk screwing up the PCB of their fightstick, and would rather do it solderlessly...and save the soldering to the kits that are usually easier for novices to work with.
I've been researching parts for the past couple of weeks, and when I finally had an idea of what parts I should use for this, I began to take my measurements and undertake the daunting task of learning to use Eagle 5.7. Since this project required me to do multiple things that I'm new at, it's been a very rough road...lots of hair pulling, and not in the fun way that involves sex, but the way that will cause me to go bald at an early age.
Step 1:
Parts, and wtf to do about getting them in a good fashion. Well, I've found that you can get LOST in parts research, because sometimes part A fits the bill pretty well, but then you find out that there's a minimum order of 5000, and even at $0.11 each, that's a pretty hefty sum to front for a hobbyist project. So we move to part B, which doesn't fit things *quite* as well, but is much more attainable, with smaller lead times, and much less of a dive for cost.
The main part in this project, what to use to make a flexible, yet firm connection to each point on the PCB that we want to break out. After HOURS of research and comparison, I found that my answer is within Pogo-Pins, which are normally used for test stations...but seeing as how I'm a modder, we're going to use it in a non-standard fashion.
Secondary part, how the hell do we attach the boards together... well remember my example regarding 5000 pieces minimum? This is the part where I saw that quote and nearly shit myself. This is probably where I spent the most time, and on a last ditch effort to try and find what I was looking for, I found my answer. This part is extremely important, because I wanted to make the user able to install this board without any modification to the case, or the PCB. I found that edge holding PCB clips are what I needed, but finding a supplier is surprisingly difficult. However, I found (as luck would have it) a local distributor that didn't require such a large order. Awesome.
Step 2:
Board layout is something I've never done. I've used many schematic programs through engineering school, but never were we given the task of board design. I figured it was about time I learned how to do this stuff, so I went with Eagle, which is able to be converted and used in damn near any PCB fabrication house in the world. Giving me loads of options when it comes to prototyping and full production if the interest is there.
Here's the thing about Eagle... it has got to be the most non-intuitive program I've ever used. Although that's probably still second to Cadence design software, which is based from a non-windows platform, and equally as hard to learn to use. The first thing I learned how to do was create custom footprints and parts, because unlike what I thought, the pitch between some of the pins on the Madcatz PCB are of a non-standard nature (2.51mm for 2 spots, 1.91mm for the other 2). After struggling and swearing through that, I found how to manipulate things, and now I can use the software fairly well, go me!
Step 3:
Making everything fit together... holy shit, what a pain in the ass. I could write for hours on how many changes and alterations I've had to make. Since most people who create PCBs don't give a shit about measurements, other than trying to cram everything into a small board, this type of step doesn't bother them. Mine, however is hugely dependent on measurement accuracy...so I ended up printing out my board layout on a 1:1 scale, and adjusting the layout based on that.
Currently, I'm finishing up my mockup of the board, and I've run to the hardware store more times than I ever have, just to fetch nylon washers, and drill bits smaller than 1/16".
Enough rambling, here's a few shots of what I've got so far:
Doesn't look like much, but basically I printed the layout 1:1, and pasted it onto a piece of proto board, cut it with a dremel to the general size of what it will end up. Then drilled all of the important holes to see if my parts all fit together and play nicely. Yes, the pogo pins are crooked, but you try drilling a hole that size and being accurate to +/-.003mm like the board house will.
The object of this was to see any obvious defects in the design, and I'm sure as hell glad I did this, because I caught quite a few things that needed to be fixed. See the corners of the board? Those are edge holding board supports, and the only ones I've ever found that actually hold the corners of the board...they're pretty fucking snazzy, and also pretty sturdy.
The board clipped in and aligned as well as I can with my horrid drilling. As you can see the board is held pretty well by those clips. Also something of note is the end header that everything will be routed to for easy access. I find that people like to use ribbon cable headers, as they keep things very nice and neat.
The pogo pins, there are two styles I'm utilizing. One of them is a cup tip, so that the header pin will sit neatly inside, and the other one is a crown tip. I'm specifically using the crown tip on the USB lines, because those are generally cut by the factory worker, so having some pointy edges will be better in catching the solder joint. You'll notice that the pins are crooked in the second picture, again...they're all off to a single direction, that results from a right handed driller and standoff holes that are mis-drilled to a slight degree. This will look WAY better when the prototypes are made, this was just to check my pitch spacing...which seems to dead on, score one for me!
Also, you may notice that my board is bending slightly. Even at 3.8oz of force, a lot of pins will cause that, I'm currently trying to figure a way to stop that from happening, more parts research... yay! /sarcasm.
What is should look like inside of the case. Currently I've got a few #10 nylon washers sitting the board up a tad, this is a direct result from the length of the pins, and also the cause of my headaches when trying to find something to stop the board bending. YOU try finding a board standoff/spacer that's 9mm, that shit is impossible.
Anywho, since everything seems to have come out fairly well, I may ship this off to be prototyped sometime this week. Researching board houses is another challenge in itself...and the rabbit hole gets deeper.....
