Soldering disaster (16x2 Blue LCD)

[Jcink]

I tried to solder my 16x2 lcd board's components together and I made a huge disaster. I have no idea how to do this correctly, I need recommendations for a soldering gun as well as exactly what type of solder to use. I bought thin solder like what's in the tutorial, but I couldn't get it to stick, it practically burned away the moment it got on the gun and had no hold on the board. I don't know what I'm doing regarding soldering and really need some advice.

Furthermore as you can see I really screwed up my board. The holes where the i2c are supposed to go got all covered up by accident. Is there a way I can salvage this at all?

[adafruit_support_rick]

"Gun"? You're not using a soldering gun, are you?
You need to use a soldering iron designed for electronics work. Please review our tutorial on soldering:
https://learn.adafruit.com/adafruit-gui ... ring/tools

You may be able to salvage the board with solder wick and a solder sucker to remove all the excess.

[Jcink]

I used a Weller sp32l with this end bit that solder, thinking I could make it work and failed. It's not a gun, sorry, just an iron. Is the tip I have just too big on it?

So for the solder and this type of project, I should get this right?

www.adafruit.com/products/145

I'll also try the wick. Thanks for the tutorial. I wish I had found that before.

[Franklin97355]

YES get that or at least regular electronics solder. What you're using looks to be plumbers solder and it is too big and there is no flux in that. I don't know where you live but a store like radio shack should have it or you may go to the local radio tv repair guy and ask for a bit.

[adafruit_support_rick]

The tip is a little bit big. See if you can get a smaller "screwdriver" tip. I generally use a 1.98mm screwdriver tip

[ggotnomoney]

Or you can do like me who had no experience soldering whatsoever and posted an ad in the jobs section. I got a few replies and found someone to do it for me at a great price. I received it yesterday and it looked so good that you would think it came like that from the factory. I am extremely satisfied going this route, maybe you should consider it.

[Jcink]

Or you can do like me who had no experience soldering whatsoever and posted an ad in the jobs section. I got a few replies and found someone to do it for me at a great price. I received it yesterday and it looked so good that you would think it came like that from the factory. I am extremely satisfied going this route, maybe you should consider it.

What did it end up costing you? At this point I am considering the same. I got to a point where I thought I was okay, but now I'm experiencing the problem this user has with no solution: http://adafruit.com/forums/viewtopic.php?f=31&p=197256

Now I don't know where I went wrong as I have verified everything is 100% pieced together correctly, so either my soldering is shoddy or I damaged the board. Sucks when you make so many mistakes in one project that when it doesn't work like this at the end it could literally be anything.

[Franklin97355]

Let's have a new picture of the final soldering to see if there are any problems we can spot.

[Jcink]

Appreciate it.

http://someimage.com/1LnK

Some of the leads look soldered together, but they aren't.

Also, now the backlight on the screen won't come on for some reason. Definitely messed this up.

[Jcink]

I obtained a free multimeter from somewhere and have been trying to test the joints. I have a few questions:

The ohm resistor that goes in the BLUE spot in the upper right hand corner... is this what makes the screen backlight come on? I connected the multimeter to both ends and I am not getting a reading of 0.00, instead it's just something like 153 or whatever. This means one of the joints is cold, right? If so, this may explain why the blue backlight doesn't come on.

I also tried testing some of the leads using the back of the arduino, and I either get readings of 0.00 or 0.02/0.01, sometimes fluxing... is even having 0.02 a problem in a continuity reading, or is there margin for error?

[adafruit_support_rick]

"Continuity" is really a measure of resistance. If you probe both sides of a resistor, you'll see the resistance provided by the resistor. Instead, you want to be looking at the ends of the traces between components.

I've attached the schematic. You should be able to see that the 'blue' resistor connects to the LCD at pin 18, and to the MCP23017 at GPB0 (pin 1). So, to check continuity, you want to probe one side of the resistor and LCD pin 18. You should see some low number; if not exactly zero, then at least close to it. Then probe the other side of the resistor and pin 1 of the MCP23017 (pin 1 is indicated by a small dot on the chip. Pins are numbered own the side from 1, and then back up the other side - pin 14 is opposite pin 15, pin 1 is opposite pin 28).

Since you're looking for soldering problems, it's best to do your probing on the component side of the shield, so that the pressure of your probes don't create a false connections inside a marginal solder joint.