How to fix this Firewire 800 header by soldering?


Unfortunately I found the headers on my computer's belkin 3-port Firewire 800 all tilted back somehow, and they snapped off when I tilted them forward to where they should be. As a quick fix, I have a smaller Firewire 800 card, but, it is not fitting for several reasons.

As a result, I may be forced to cannibalize the headers from the smaller Firewire 800 card and solder them onto the broken card. I need a fast fix because this is an important computer.

Generally as you can see below there are three headers on the broken card, and the central one looks quite damaged.

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What are the steps that I should go through in thinking about whether I want to do this or not, and what are the tools I should have available? I have solder and flux, decent soldering iron, microscope. It looks like I could go for the left and right header for replacement. What do you think? Does it look possible, and where should I be most careful?

If there is a short video guide on soldering headers that is your very favorite (using the best technique), please feel free to include.

Best Answer

Disclaimer: The answers I am about to give you are personal opinion based on my own experience. Do keep in mind though, that I own a full range of Wellers from small to large and some hot-air tools.

  1. A: Should you just use the connectors from the smaller card? Only, and I do mean only if you are 100% sure you will not want to use the small card again, no matter the outcome. Successfully harvesting a connector with both through-hole and surface mount pins without deforming it is not the easiest thing, but leaving everything on the original board in tact to be able to put them back, is downright hard without a semblance of hot air tooling made for that purpose.

  2. B: How do I think you'd have the best chance of success? Heat the board from the bottom with hot air at about 320 degrees Celcius. "Commercial hot air guns" often show the air temperature inside without a lot of accurate knowledge about the temperature of the air hitting the board, if the solder doesn't become gooey or liquid within/after 10s, turn it up a little. Be aware, that at this point, you are probably already getting close to severely stressing any processors near the connectors and you are closing in on the point of no return fast. If the solder is nice and gooey or liquid, start lightly pulling on the connector with some heat-proof tool and switch to heating the topside. Since normal hot-air guns have a lot of poorly controlled airflow and "big mouhts", you are now genuinely heating half the board up to 300 to 330 degrees. This may loose other things or damage sensitive processors, you may be lucky, but don't expect to be using the donor card again.

  3. What do I think you should do in earnest? Find out the type of the connector. I'm not quite knowledgeable about firewire series, but maybe someone else here is. Buy a couple from DigiKey or Mouser, clean off all three mount points, make sure holes are opened, solder in the new connectors, maybe see if you can think of a way to fix them a bit stronger and see if anything works.

  4. If you do everything right with putting new ones on, will it work? There's no guarantee. It looks to me all three ports might be potentially saved. Though for the middle one check if the missing pad is connected to ground on the other ones and replace that by a wire to the nearest reachable ground or a wire to another point that does the same as that missing pad on the other connectors. There doesn't seem to be very extensive damage, but I have been fooled before and a picture is never like really holding the PCB.

If you have a "day job" that pays okay, chances are your time and the materials needed are going to overtake the cost of a new card quite soon. Consider that as well. If you want to try it because you find it exciting and no cure as a result is okay for you, go for it.