First soldering project, QFR [FIXED] THANKS!

[shreebles]

Hi geekhack,
It's been a while. I'm not usually very active around here because I live in Europe and many of the discussions/offers/group buys here are US/NA centered.
HOWEVER it'd be really nice if someone could help because I do believe that GH is the place for soldering/modding enthusiasts, especially when it comes to the Quickfire Rapid.

This board has a strange quirk in that issues with the keys QWER UIOP and scroll lock seem to appear commonly and frequently for very different reasons.

In my case however, I did not experience the issue until I took a soldering iron to my QFR to convert it to ergo-clears. I'll try to make a long story short to save you some time.

After converting everything to ergo clears, most of the board works fine, with LEDs even but the keys QWER UIOP and scroll lock do not work.
I desoldered and re-soldered everything in the last 3 hours, to make sure that spacing between the metal plate and PCB is adequate (so the metal plate doesn't short any connections). Some people had the same problem and loosened the screw on the back because apparently it got too tight in the case. Of course mine is outside the case, but it doesn't work either way.

Three solder joints are bypassed with insulated wire on this keyboard, one already was (refurbished unit) and I followed the example of the first to fix the left Winkey, I also did it on the left ALT not because it was broken but because it's such a common issue I wanted to avoid in the future. These joints look sketchy as **** but they all work fine, something is wrong with this board or the controller but it's nothing I can see with the naked eye.

I have a second QFR so I was able to cross-check and rule out a few things

- It's not the cable
- It's not the internal connector cable
- It's not the USB port, or the PS2 port for that matter, same behavior

Maybe someone had a similar experience while modding this thing? Did I mess up the controller somehow, possibly?
Things to note:

-I am a noob to soldering and especially desoldering
-I may or may not have touched some of the traces with the soldering iron on accident
-I have good quality solder but my iron is pretty old and has no temperature regulation. It's possible that it got too hot
-The solder joints on the controller are too small for me to desolder and resolder them

I am actually considering baking the PCB in the oven, like some people have baked GPUs that had broken solder joints...

Unless someone has a better idea? Any help appreciated. 

PS: Funny thing, there are even people who have the same issue despite having a completely different keyboard. Maybe they all use the same/similar controller:
https://geekhack.org/index.php?topic=60046.msg1381549#msg1381549

[Spopepro]

Do you have a multimeter?  Something that can do a continuity check would be massively helpful for troubleshooting.

You appear to have lost a row of your matrix.  Either a connection is being lost due to a component joint breaking, or your rewiring has missed a connection, or.... something else.  In any case, I'd try and find the pin on the microcontroller that is responsible for that bank of keys, and then poke around to try and find where the discontinuity is.

[shreebles]

You appear to have lost a row of your matrix.  Either a connection is being lost due to a component joint breaking, or your rewiring has missed a connection, or.... something else.  In any case, I'd try and find the pin on the microcontroller that is responsible for that bank of keys, and then poke around to try and find where the discontinuity is.

Thanks for providing insight! Now, at least I know what's broken. Possibly it's not that the soldering iron was too hot but rather not hot enough, so I had to keep it in one place too long while desoldering.

I do have a multimeter somewhere, and I knew that you can check PCBs with it but did not know how. All I ever used it for was to check if PSUs delivered the correct voltages on each line. I'll have to look for a tutorial tomorrow because I know how to measure when there is current on the line, but do not know how to determine if a connection is faulty.

[Spopepro]

Easiest way to do so is with the diode setting.  It should beep, or show some reading, when a current is allowed to flow (i.e. there's continuity).

[suicidal_orange]

I knew that pattern sounded familiar - it's the same strange matrix split as my Ducky!

It's a bit of a long shot, but if you can see a connection between the Pause key (which I'm assuming works?) and Scroll Lock solder a jumper wire there and it might just fix it.

[shreebles]

I knew that pattern sounded familiar - it's the same strange matrix split as my Ducky!

It's a bit of a long shot, but if you can see a connection between the Pause key (which I'm assuming works?) and Scroll Lock solder a jumper wire there and it might just fix it.

 
You are the MAN!
IT WORKED! I cannot believe it, I am so happy right now
Can I buy you a beer?

Typing this from the newly completed and fully working board.

Easiest way to do so is with the diode setting.  It should beep, or show some reading, when a current is allowed to flow (i.e. there's continuity).

After figuring out that the triangle and line is the mode to check continuity on my cheap multimeter (no sound) I poked around a bit on the PCB to learn how it works, I didn't really know what I was doing.
But I did pay special attention to the area around Scroll Lock and as it turned out there was some connection between it and the Pause key. Or rather, there was supposed to be some connection there as  I could tell from the pins (two pins aligned means there is a wire running across on the other side of the PCB), but it didn't work. So I just bridged the connection using the crude methods available to me and to my complete and utter astonishment this has fixed the issue.



This adds to the total number of ghetto fixes on this keyboard, up to 4, three of those I did commit 


A million thanks to everyone involved, especially suicidal_orange 

[suicidal_orange]

I knew that pattern sounded familiar - it's the same strange matrix split as my Ducky!

It's a bit of a long shot, but if you can see a connection between the Pause key (which I'm assuming works?) and Scroll Lock solder a jumper wire there and it might just fix it.

 
You are the MAN!
IT WORKED! I cannot believe it, I am so happy right now
Can I buy you a beer?

Can you see the other side of the board to know what you've done there?  I only ask because although it's working I'm not sure your fix is correct - it looks like you're bypassing the diode.

If you're happy to keep using it as it works feel free to but if not a pic with the fix removed would be good.

Mine's a cider, but as a perfectionist I won't accept until it's fixed properly )

[shreebles]

Can you see the other side of the board to know what you've done there?  I only ask because although it's working I'm not sure your fix is correct - it looks like you're bypassing the diode.

I could but I would have to desolder and resolder the whole board again, and I did it twice this weekend. My first time, it took over 10 hours. Yesterday, I only needed two. But I would need at least 1 and a half to do it all again, and my soldering iron keeps getting worse. Also, a lot of the spots for the solder joints are really f**d up by now and I would probably need ANOTHER quickfix to bypass a joint.
It's possible that I bypassed the diode - but key rollover seems pretty good, I can press more keys at once than I would ever need. Not NKRO despite using PS2, but more than 6KRO.

If you're happy to keep using it as it works feel free to but if not a pic with the fix removed would be good.
Mine's a cider, but as a perfectionist I won't accept until it's fixed properly )

What do you mean by cider? Non-native speaker here...

I am a perfectionist too but I spent way too long this weekend trying to get it to work, and right now I'm just glad it does. Being really new to soldering electronics, I don't feel comfortable trying to improve the fix on this board.
But I do hope to do more projects like this in the future, with a quality soldering iron (and using a quality PCB) to learn more and begin to understand everything better.

[suicidal_orange]

Cider is an alcoholic drink made from fermented apple juice, best served chilled on a sunny summer day.  If you don't have any in your country a light beer or lager will do just fine

Probably a good idea to leave the board alone if all seems well, it's impressive you got away with so few fixes doing the whole board twice.  Enjoy the ergo clears and I look forward to seeing pics of your future projects

[shreebles]

Probably a good idea to leave the board alone if all seems well, it's impressive you got away with so few fixes doing the whole board twice.  Enjoy the ergo clears and I look forward to seeing pics of your future projects

Yeah, I can actually see more solder joints breaking if I desolder with this crappy iron again. I consider myself lucky to have my learning project with no previous experience turn out well after all.
 As for next projects, I may be going for a Phantom build next. I don't like 60% keyboards, the smallest layout I could see myself using everyday is the Keycool 84, and no ISO version exists.
A Phantom ISO with 1.5 modifiers and a 7u space would be the perfect platform for my Cherry Dye-subs.
As for switches, I'm considering ergo-clear (lubed, this time) and Gateron blacks. And swapping for blues or whatever would be so easy, too 

Cider is an alcoholic drink made from fermented apple juice, best served chilled on a sunny summer day.  If you don't have any in your country a light beer or lager will do just fine

I should've known!

Of course I do know what Cider is. It's easily acquired even here in Germany. I was simply confused because you mentioned the Cider in the same sentence as being a perfectionist with keyboards so I thought it was just some figure of speech unknown to me. I'll buy you a Cider of course, can you PM me your Paypal address?

As for me, I'll stick to beer, but definitely not light ones!  ) I'll have you know that I have unfortunately become somewhat of a beer snob. The light stuff won't do.
You should try a few different beers sometimes, even if you prefer Cider I know some beers that could really fit your taste. Belgian Geuze is a delicious, dry and sour beer made with wild yeasts and fermented in the bottle - just like Champagne! It tastes quite similar to Cider, some say better 

[Spopepro]

Shreebles,

It might not totally be your iron--you are probably exhausting the flux in the solder.  I find that when I am doing a whole bunch of re-work I need to add flux to make it all go smoothly.  I put a little spot of it on each joint I am working on and it makes desoldering/resoldering much, much faster and easier.  You can tell when the solder is tired of being redone--it gets lumpy, hard to melt, and very sticky and kind of putty like.

Do be careful--do not get plumbers soldering flux, which is highly corrosive and designed for flowing brass with a torch.  You need pine rosin flux.

And the best beer is the one served in a big mug out of a cart in a park on a warm summer evening.  Unfortunately, not so much of that here in the states.