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I bought a small "fancy" protoboard from Sparkfun. It includes a solder mask and through plated holes(double sided).
Now I'm trying to do a simple circuit and I can't seem to figure out how to drag solder across the board. The solder mask keeps the solder out of where I want it to bridge and it ends up just going through the plated holes and accumulating on the other side.
How exactly do you do point to point wiring?
Various ways:
After you have done this long enough you put a goodly blob of solder onto each pad then feed solder rapidly onto the iron to forma growing floating molten blob between pads. Then you perform a Vulcan mind meld and the floating blob reaches out and joins hands with the excess solder on the pads on each side and wicks onto them both. You pull the iron away as it all starts to happen as otherwise the molten blob will be pulled onto the pads by surface tension. At least, I think that's how it goes – it gets a bit dim around the mind-meld part after you have done enough of these to make it work enough of the time to be useful. Problems include wicking hot solder onto cold solder is liable to leave the driest of joints, and if you touch or approach it with a hot iron while working nearby the blob will gleefully liquefy and rush off onto one or other pad. Murphy says you never see the crucial ones go.
Easier, better quality, will not vanish in a puff of soldering iron:
Use wire, probably single strand. Tinned.
Either bend one end with a few mm bent at 90 degrees, place bent end down one hole, tack solder, swing wire across 2nd pad to be joined to. Tidy. Cut off excess wire flush. Or ...
As per (2) above but wire is on surface at both ends. Can avoid wire in holes, easy to suck off latterly, easy to accidentally remove.
Place U of wire into holes to be joined, LIGHTLY bend to retain in position. Cut wire now or after soldering. If now bend ends lightly so link will stay in PCB until soldered.
Added
@Earlz - I didn't realise you meant that you had pins in the holes.
If pins were long and have been trimmed, bend leads over as required before trimming - as others have said.
BUT you can get superb wires that will often fit in hole with pin.
Kynar or Tefzel or other flurocarbon insulations.
Super thin - down to 30 gauge = 0.002 inch = 0.05mm dia.
Very good for links etc. Highly soldering iron resistant. A coil of Kynar can be wrapped around an iron tip and maintain its mechanical integrity, while looking "a little sad."
Jaguar Kynar and Tefzel wirewrap wire here down to 30 gauge ~= 0.002" dia. =~ -.05mm dia. Goes down holes nicely. Super super super hard to strip. Use sharp wire cutters and magic. Other irrelevant to this thread but needed wire products.
http://en.wikipedia.org/wiki/Polyvinylidene_fluoride Insulation is highly heat resistant. Can put end down hole with pin and solder or make a small loop around pin!
DuPont™ Tefzel® is a modified ETFA (ethylene-tetrafluoroethylene) fluoropolymer available as pellets or as powder for rotational molding. Tefzel® ETFE resin combines superior mechanical toughness with an outstanding chemical inertness that approaches that of Teflon® fluoropolymer resins. Tefzel® features easy processibility, a specific gravity of 1.7, and high-energy radiation resistance. Most grades are rated for continuous exposure at 150°C (302°F), based on the 20,000-hr criterion.
Here's an idea that I think will work ok, though I haven't soldered it yet (I've tried it physically, though): get some 22 gauge STRANDED wire, and a small manual wirewrap tool (I had an "Cambion" one on hand).
Use single separate strands of the 22 gauge to wirewrap between pins & leads & wires. Then solder the pins/leads/wires to the solder pads. I tried wrapping IC pins & solid wire and header pins, all wrapped fine. This also helps to hold parts in place.
Often you have to bend the ends of the wires or leads on the solder side to cross the gap between the pads you want to bridge. You may find the boards with breadboard-like patterns of joined holes easier to work with, though you can't create as dense a circuit with them.
Electronics solder is usually chosen from alloys which have a have little distance between the temperature at which they solidify (solidus) and the temperature at which they melt (liquidus), so they flow quite freely but resist bridging gaps. There exist solder alloys with a larger temperature range where a mixture of solid and liquid is present which can as a result have a paste-like consistency and fill gaps, but they're not usually used for general electronics assembly. And with any alloy, practice and experience can lead to improved skills for fully exploiting its capabilities.
I know that's a bit older topic but helped when I was looking for the right wire name to buy. Again, Kynar/Wrapping wiring is the way to go - yes, they are more expensive than common wire!
Save the clipped Leads
I also save most of the components leads that I clip to use as a bridge. They are not insulated, but works great when you need a tiny bit of "wire" to join two ICs' pins or to build the ground and Vcc nets. It also looks very neat as is easy to keep straight or make right angles.
SMD 0805
I realized another day that SMD size 0805 are perfect to solder on green protoboard (the one with solder mask). They are 2mm long, so they'll fit perfectly between the 2.54mm holes - even if you already have some other through role or SMD component on the same pad.
Just add a tiny bit of solder on each pad, put the component on the top and re-melt (reflow) the solder by touching the pad on the opposite site (no need to touch the component). This will "glue" the component in place so you can later add a bit more of solder on each side. Passive SMDs are much cheaper easier to source than through role ones IMO.
It may not be designed for solder bridging - if you mention the part number this can be confirmed.
Anyway, proper point to point wiring is where you use a wire straight from one hole/tab/whatever to the other. If you want some nearby pads joined together you can either use some bare wire and solder it across the necessary pads, or you can use the component leads where possible also (i.e. don't clip them and use the extra length)
You may want to look at stripboard/veroboard.
