soldering tips needed

[tony.silveira]

hey guys,

i'm about to start the mounting of the led's around my joysticks, to be driven by an ledwiz.  i have the led's and also the resistors needed but am asking for advice on the best way to solder them.  i'm used to soldering soft wires together but each of these parts has hard wire legs (pic attached).  also, on which leg does the resistor get attached to, the short or long leg of the led?

fyi, once i figure out how to solder these legs together, each one will have heat shrink around it to prevent any shorts.

thanks of any input

[Mysterioii]

Doesn't matter which leg you solder it to.  As far as how to solder them, I like to trim the leads fairly short (like a centimeter, ballpark) then hook them with needle nose pliers.  Both on the LED and the resistors.  When you hook them together it makes a stronger mechanical connection, you're not relying on the strength of the solder (not like anyone will be tugging on them, but it's how I was taught... plus when you hook them it holds them in place while you solder.)  Then a little touch of solder and slide some shrink tubing over 'em.

[tony.silveira]

Doesn't matter which leg you solder it to.  As far as how to solder them, I like to trim the leads fairly short (like a centimeter, ballpark) then hook them with needle nose pliers.  Both on the LED and the resistors.  When you hook them together it makes a stronger mechanical connection, you're not relying on the strength of the solder (not like anyone will be tugging on them, but it's how I was taught... plus when you hook them it holds them in place while you solder.)  Then a little touch of solder and slide some shrink tubing over 'em.

hooks, sweet jesus why didn't i think of that.  thanks a ton man!  and just to confirm, it doesn't matter which leg the resistor goes on?  that sounds crazy to me!  does it matter which leg is connected to the + terminal in an ledwiz?

this is my first time working with led's so please excuse the rookie questions...

thanks again, t

[HaRuMaN]

Either leg is fine for the resistor.

[Mysterioii]

Doesn't matter which leg you solder it to.  As far as how to solder them, I like to trim the leads fairly short (like a centimeter, ballpark) then hook them with needle nose pliers.  Both on the LED and the resistors.  When you hook them together it makes a stronger mechanical connection, you're not relying on the strength of the solder (not like anyone will be tugging on them, but it's how I was taught... plus when you hook them it holds them in place while you solder.)  Then a little touch of solder and slide some shrink tubing over 'em.

hooks, sweet jesus why didn't i think of that.  thanks a ton man!  and just to confirm, it doesn't matter which leg the resistor goes on?  that sounds crazy to me!  does it matter which leg is connected to the + terminal in an ledwiz?

this is my first time working with led's so please excuse the rookie questions...

thanks again, t

Nope doesn't matter which side you put the resistor on.  They're just there for "current limiting" and they'll do the same job on either side of the diode.  The long leg is the anode and the short leg is the cathode....  when configured properly the current flows from the positive supply into the anode and out the cathode to ground...  I haven't actually wired up an LEDWiz (have one sitting in a box somewhere) but I believe it's outputs are active low, current sinking outputs.  Meaning there's a shared supply (+) terminal and then the individual output pins go low and sink current to light an LED....  At least I think that's how that board is configured, you may check the diagram first.  If that's the case, then yeah the + terminal you're seeing would be connected to the long leg and one of the output pins would be connected to the short leg, with the resistor somewhere in between on either side of the LED.

[Nephasth]

Also, if it's easier for you, the resistors don't need to be soldered directly to the LEDs. They can be several feet away from the LEDs in the circuit in a more convenient location.

[tony.silveira]

Also, if it's easier for you, the resistors don't need to be soldered directly to the LEDs. They can be several feet away from the LEDs in the circuit in a more convenient location.

didn't think of that either, sheesh!  i can just run wire to my ledwiz and have the resistors installed in the screw terminals and then solder the wire to that.

thanks for the input guys!

[knave]

Nobody's gonna tell him that he can buy new tips at Radio Shack?   

[Mysterioii]

No prob.  BTW even if I'm just soldering wire to an LED or other component, I like to tin the wire first then hook it with the needle nose pliers just like if I was soldering two components together.  Mechanical connection... that's how I was taught, and it stuck...  

[alfonzotan]

There's always Old Faithful when it comes to soldering tips:  "The bigger the blob, the better the job!"

[tony.silveira]

Nobody's gonna tell him that he can buy new tips at Radio Shack?   

 

[compute]

I'm a big fan of those "handy helper" things with the two aligator clips that can be positioned.  If I need more hands, I'll bring in a hemostat or two to hold the thing together while I solder.

[PL1]

+1 to solid mechanical connections and tinning your wires before bending and soldering them.

If you don't have rosin core solder, a little rosin soldering paste flux is your friend.  You can apply it with a toothpick or dip the wire/component into the container. 

Make sure you get flux like Radiio Shack P/N 64-022 which is labeled "For electrical and electronic applications." DO NOT USE ACID FLUX which is intended for metal repairs.

Clean up the joint area afterward with a little isopropyl alcohol on a brush or cotton swab.

Also, if the components don't reach a high enough temperature, you can get a cold solder joint.

General soldering info on power ratings, tip selection, and flux.


Scott

P.S. In case anyone misunderstood Alfonzotan: "The bigger the blob, the better the job" is an old soldering joke.

[shponglefan]

Nobody's gonna tell him that he can buy new tips at Radio Shack?   

That was my first thought when I saw the thread too. 

[eds1275]

Nobody's gonna tell him that he can buy new tips at Radio Shack?   

Me 3. I actually just looked all over town for tips that fit my iron and couldn't find any in stock, so I busted out the dremel and ground my old one back into a point. It worked like new. I still ordered some new ones online when I got home though.