Dangerous Prototypes Open Source Hardware

DIY Bus Pirate PCB

January 05, 2010, 05:45:20 pm

I wanted to test out my new setup so I tried to create a home made bus pirate pcb, all in all the results were pretty good, the board came out real well and drilling didn't give me any problems, the small vias tend to be a bit weak so spraying over a protective coating is pretty important.

To do the through hole plating I use small wires if I can afford a bump on the board where I soldered it or fill it with a conductive paint, if using conductive paint you can simply put some sticky tape over the board before drilling to prevent the paint from going anywhere unintended.

I've made some pretty stupid mistakes in the past with my layouts so I prefer making a cheap prototype first, what do you guys prefer, going cheap or doing a professional prototype run?

[EDIT]

Oh, I did a single layer board because I overexposed the first attempt which was double layer, the results are near perfect with double layer since alignment when using photo resist is pretty good.

Re: DIY Bus Pirate PCB

Reply #1 – January 05, 2010, 05:48:23 pm

Nice. I always do prototypes with inkjet on photo-transparency. Good to QFN and 0402, never tested smaller. I don't do double-sided boards unless there's only a few jumpers though. Now I'm making so many boards every month it's cheaper (time and materials) to just send it off for a panel, unless I need something RIGHT NOW.

Re: DIY Bus Pirate PCB

Reply #2 – January 05, 2010, 05:49:45 pm

Adding, the Bus Pirate was prototyped on my own boards until v2. v2 and v3 each took two tries to get 'right', which is frustrating when you're paying for the boards

Re: DIY Bus Pirate PCB

Reply #3 – January 06, 2010, 02:01:29 am

I etched a V1 board with the toner transfer method from a magazine page. I did 2 prints on one copper... One came out well, but the iron smeared the other.

I couldn't really get great holes drilled in the board that worked... They all seemed too big, probably from hand wobble. I'd likely need a drill press for it.

Re: DIY Bus Pirate PCB

Reply #4 – January 10, 2010, 08:24:35 pm

I didn't think a drill press would make that big of a difference but boy was I wrong. I use to use a dremel for drilling pcb holes and it worked fairly well but I did lose a pad every now and again.

Getting a new drill was partly why I tried making this board, it's pretty big and not cheap considering I'm using it only for pcb drilling but works real well, I've tried drilling holes down to 0.4mm with no problems.

Re: DIY Bus Pirate PCB

Reply #5 – January 11, 2010, 08:47:37 am

What kind of drill press are you using? I love my little Proxxon, and I used to store it under a dorm bed

http://hackaday.com/2009/02/27/tools-pr ... 115tbm220/