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eviltwin wrote:I am almost done with my pcb design, It seems the soldermask adds a lot to the cost of the board, do you beleive I can solder the cyclone II, caps, regulators, etc on the board without the soldermask?? Or will it be a disaster?

BTXSistemas wrote:Sorry mrand. I usually solder QFP's TSSOP packages using a single iron solder (cheap, made in China) in a PCB without soldermask, the "trick" is using in example a "flux gel", you dont need to solder each pin at time, you apply the gel, and then pass the iron solder over all pins together, no short circuits at all. although the "view" of the PCB finished is not the better.
It's not bad, for a beginner.
Also, you can try with a piece of "paper tape" near the pins line, to simulate the solder mask, solder all pins in that side, and then take the tape out, and voila !! a better "view" of the board. Repeat for the four sides of the IC.

PS: Hope you understand my mean....my natural language is not English.

WadeH wrote:

BTXSistemas wrote:Sorry mrand. I usually solder QFP's TSSOP packages using a single iron solder (cheap, made in China) in a PCB without soldermask, the "trick" is using in example a "flux gel", you dont need to solder each pin at time, you apply the gel, and then pass the iron solder over all pins together, no short circuits at all. although the "view" of the PCB finished is not the better.
It's not bad, for a beginner.
Also, you can try with a piece of "paper tape" near the pins line, to simulate the solder mask, solder all pins in that side, and then take the tape out, and voila !! a better "view" of the board. Repeat for the four sides of the IC.

PS: Hope you understand my mean....my natural language is not English.

I'd like to second 'BTXSistemas's reply with the caveat that a microscope will make it _much_ easier. It should also be noted that, at least for the case of the Cyclone II in the PG240 package, soldermask is not an issue: the pins are so close together that there isn't any mask between pins.
Wade Hassler