Surface Mount Soldering + PCB questions

ncrn · World Chat Champion Joined: 24 May 2006 Karma :

Hey; I'm at uni at the moment studying robotics, which means I build a lot of electronic hardware. I've been experimenting with making my own PCBs and I've gotten pretty good at etching PCBs and soldering through hole components to them, and while this works well everything comes out large and its not very neat, and I feel a bit limited by what I can do.

I've done a bit of research on surface mount soldering and it looks like something I can do, but I was wondering if anyone had advice about decent soldering irons to use, as I use the uni irons at the moment and they are quite large so I'm not sure how good they would be.

Also does anyone have any advice as to how I can join top and bottom layers of PCBs in a good quality method, currently I'm poking bits of wire through the two layers and soldering on each end, its not neat and its very time consuming. Looking at professionally done boards they tend to have the gap inbetween layers plated, how is this done?

Also another question how do they make the boards green and solder resistant?

Not sure if all the questions are answerable but any advice would be great as I'm hoping to make a really good quality robot for my final year project rather than the sky-wired bodge-bot I built this year Laughing

.

Thank you.
____________________
Past: 55 Sym Jet, 91 ZZR250, 03 NSR125R. Present: 97 ER-5.
https://www.nsr125.co.uk - NSR Owners forum.

MattHirst · World Chat Champion Joined: 25 Jun 2006 Karma :

I thought most 'professional' PCBs were generally multi layer boards, where they have tracks on the top and bottom, but actually on different layers in the middle aswell.

As for irons, you'd want something fairly low power i presume, and obviously with a fine tip.

Not sure what you mean by solder resistant, the green colour is just the colour of the board that they etch onto i think. They may clean the boards after soldering the components on. But on large scale production (tellies or whatnot) then it will be robotics soldering anyway so they will use exactly the right amount of solder and flux, hence it will look VERY neat.
____________________
It's all fun and games until someone gets hurt, then it's bloody hilarious!!!

Stoo · PoshBoy Joined: 11 May 2006 Karma :

Im-a-Ridah · World Chat Champion Joined: 20 Oct 2006 Karma :

Some videos on youtube show some good techniques for it, but look's like you'd need some practice to get it right.

https://www.youtube.com/watch?v=3NN7UGWYmBY

What microcontrollers do you use for your robotics at uni?

ncrn · World Chat Champion Joined: 24 May 2006 Karma :

Perhaps the green stuff is just the board type, I will have to look into that.

Just looked up what a reflow soldering oven is and nope there is nothing like that which I have access to at uni, and I doubt I could afford anything like that.

The video is great though, I'm amazed at some of the techniques he uses especially when he is basically shorting tracks but they don't remain shorted.

At the moment we are using PIC Micro controllers, but I've played with arduinos and we're looking at ARM processors soon, also briefly looked at XMOS chips but they are a bit crap for mobile robots due to their lack of ADC.
____________________
Past: 55 Sym Jet, 91 ZZR250, 03 NSR125R. Present: 97 ER-5.
https://www.nsr125.co.uk - NSR Owners forum.