Electronics Help-Needed: Motherboard tray docking circuit

The case-half of the PCB is designed.
http://www.captainslug.com/modding/mk6_plug-bus_ch_pcb2.gif

The case-half will be only female connectors while the tray half will be only male. This made the traces easier to do since Male and Female connectors have reverse pinouts allowing me to simply mirror most of the elements.

The last part to design is the front panel interface PCB.

 

The front-panel PCB is finished.
http://www.captainslug.com/modding/mk6_plug-bus_fp_pcb2.gif

Feedback is appreciated.

 

After some concerns with using D-Sub connectors I broke down and decided the use high-amp (4.5AMP max!) capacity Mill-Max Pin Header, which look like this.

One row of 100 pins on each PCB makes the traces much less complicated and allows me to use wider traces for almost everything. In other words EVERY is connected with an overkill amount of trace so this should be a very durable device. These PIN headers also have a longer service life. I also added optional board underlighting LED sockets to opposing corners of all the boards for an aesthetic touch.

All of this meant redoing all three boards, but in the end I'm much more satisfied with the results.
This PCB will attach to the motherboard tray
http://www.captainslug.com/modding/mk6_plug-bus_th_pcb3.gif
And it will dock into this PCB which will be hard-mounted in the case
http://www.captainslug.com/modding/mk6_plug-bus_ch_pcb3.gif
And all of the front panel connections will be forwarded to this PCB
http://www.captainslug.com/modding/mk6_plug-bus_fp_pcb3.gif

The case-half and front-panel PCBs will interface with eachother through a rounded floppy cable instead of a D-Sub. This will not only reduce weight and improve cable management, but it will also make the end unit much cheaper. The revisions I made reduced the end-cost by atleast $20.


And my last question is: If anyone knows of a good source, I need some 5V or 12V push solenoids with a low current draw and 100% duty cycle. Force application is not an issue here I simply need one or two solenoids to lock the tray in place when the machine is turned on.

 

I've begun ordering parts for this project and after discovering no viable sources for double-sided 3oz copper-clad board I alleviated the problem by making the case-half PCB single-sided like the rest of the boards. This allowed me to buy more affordable 3oz single-sided copper-clad board from eBay.
I now need to decide on an etching method.

 

I've seen the laser printer iron on method work quite well.

 

I did my very first etching with H²O²+HCl, was much easier than expected, and the pcb was perfect. only keep caution on the (poisoning) gases

 

Sorry if this has been mentioned, but are all the traces for the PATA cables the same length? That's definitely something you need to take into consideration since it's a parallel method and is therefore subject to rather tight packet delivery timings.

 

The new board design is only for power cables. The drive cable interfaces will be through SATA cable extensions.
I revised the schematic and board layout in Eagle and I'm waiting to hear back from someone that has access to PCB milling equipment. If they can help me get the boards made it would save me alot of time. Even automating just the drilling would be a great help.

 

Any news.
Sounds interesting. I hope it's still going ahead, forget the patenting, i just want to know how well it works, and how it looks.

J.

 

Despite what some of the feedback you have gotten has said, you may not need 3oz copper PCBs to accomodate the current loads, especially since you have many unused pins on your connectors. By simply splitting the power lines between several pins (especially the 3.3v ones, as I believe they draw the most current) it may be possible to decrease the required weight of copper to an easier to find 2oz/sq ft, and making the board double sided, for additional "copper weight"

Check this calculator, for the width needed for the traces, (the external widths are what you need, as the traces are external. I would stay with the default 10 degree temperature rise maximum)
http://circuitcalculator.com/wordpress/2006/01/31/pcb-trace-width-calculator/

One thing you need to be aware of, plated copper does NOT have the same characteristics as the initial layer of copper on the PCB, it is much more resistive. Many pcb's are made "1 plate 1" meaning a 1 oz/sq ft initial layer, and then an additional 1 oz/sq ft layer plated ontop of it. I am unsure of the thermal characteristics (although I expect they are linear), however the resistance drop is much less than expected (~25%) when using 1 plate 1 as opposed to 2 oz