> On Jan 27, 2016, at 7:48 AM, Ethan Dicks <ethan.di...@gmail.com> wrote: > >>> >> >> Practically, I would not want to use 60 way connectors and cable. They are >> not as easy to get as the 40 way ones. > > I just did some pricing and 60-way cable is a touch pricey. Through > cable surplus vendors, I saw one quote of $1.33/ft and from the same > vendor, prices close to $0.30/ft for 28-34-way (you need twice as many > feet, of course, but it's still half the cost. Not a big deal for one > 10' run, but trying to cable up 4 RK05s, for example, it would start > to add up). 3x 40-way wouldn't be too bad, if designing from scratch > (I totally get the design goal of a simple double-sided paddle card to > simplify the construction of that - I'm not complaining about Guy's > design, just investigating costs for different methods. For just one > pair of paddle cards and one set of cables, the differences aren't > going to be enough to matter. Wanting/needing multiples for multiple > systems or drives might start to tip the balance). >
I just ran some numbers (Digikey*, so YMMV) and here’s what I came up with: 60 pin connectors (PCB & cable ends): $46.60 4 PCB connectors 8 cable connectors 2 10’ 60 conductor cable: $42.12 40 pin connectors (PCB & cable ends): $50.46 6 PCB connectors 12 cable connectors 3 10’ 40 conductor cable: $45.30 I believe when I started these, I looked at both. Given that the 60 pin solution is marginally cheaper (going with new parts which if I’m selling that’s what I use) and results in fewer connectors (and was simpler to route). Note, that *if* I do end up selling the paddle boards, I’ll sell just the boards and the connectors on the boards. I will *not* be selling the cable itself (nor the cable connectors). As you can see from the above, any solution is going to be expensive. This does not include the boards (since the price for either solution is the same). I just wanted to illustrate the comparison between 60 and 40 pin cables. TTFN - Guy * - I used the same family of connectors for both (from 3M). The only difference was the total number of pins (60 vs 40). This wasn’t the most expensive solution either and was pretty close to the cheapest as I recall but I this is what I’m using for my “prototype” run and will probably investigate more fully if/when I do a production run (of course if folks want just the bare boards they’re free to “do their own thing”).