What am I doing wrong?

[Timh]

Hey, lurker and first time poster here. It's been a while since I've built anything but lately I've been dying to get back into it, so I got myself a 51x PSU and rack. I also got a new iron tip, and after my first day of soldering the thing was shot. It kept sucking up all the solder so my joints would bubble at the top. I think it was due to using a wet sponge to wipe it clean. So tonight I went to Radioshack (desperate times. it was 8pm) and got a new tip and a brass wire sponge. My joints got cleaner for a while, but then they started to "bubble" and not get sucked through to the other side, and the tip of my iron is chipping away. So...what am I doing wrong? Do I wipe it off too much, and not keep it wet enough? Why are my joints bubbling up? Will my joints still make a connection? Any help will be greatly appreciated as I can not WAIT to see my finished product. Thanks!

 

[abechap024]

What kind of solder are you using?

 

[berkleystudios]

And what kind of iron are you using? How hot does it get?

 

[Timh]

Alpha Fry 60/40 and a Weller SP40L 40 watt. I used to use leadless solder when I first started, so I thought that was the problem, but it's still happening after I switched over to real solder.

 

[JohnRoberts]

Rosin core solder should not be a problem.

Is iron running unusually hot?

JR

 

[Timh]

Eh. Not too sure. How can I tell? Is it almost necessary to have an iron with adjustable power?

 

[riggler]

Have you tinned the tip of your iron? I use a wet sponge to clean my iron tip often. Make sure that your sponge is REAL sponge, and not synthetic. Real ones get hard when dry. The tip of your iron when hot should look like clean wet solder.

And is it maybe technique? With a tinned tip, heat up the parts for a good few seconds, then feed your solder onto the joint. Keep it still while you remove the iron. You probably already know all this, maybe like other people said your iron temperature isn't right.

 

[abechap024]

I don't know what kind of iron you have, but I remember trying to work with a crappy one in the past and the tips would just get eaten away and it was a general PITA experience...So I don't think its anything you are doing wrong.

 

[Timh]

It's working better now, and I sometimes get great joints. I feel like a 40 Weller shouldn't be the problem. I always tin the tip, but maybe I wipe it on the sponge too much because it's distracting to have an excess pool of solder on the tip. Anyways- My MAIN concern is- my joints are still making contact, right? even if they're not a perfect small little cone and being sucked all the way through to the other side?

 

[riggler]

Can you post a picture of your hot iron tip and also an example joint?

 

[abechap024]

If the solder is melting, and not being sucked through the hole (51x are dual sided circuitboards right?) Then its def. not your soldering iron, Its a solder problem. Or your not holding the tip on long enough (but I imagine you are)

If its not getting sucked through and your worried about it you can always flip it over and solder the other side.

 

[Timh]

Not the best pictures, but there ya go.

 

[PRR]

Those joints are terrible. You melted the solder and set it on the pad/lead. What you need to do is *heat* the pad and lead, *then* let the solder melt on the pad/lead.

Imagine ice-cream on a hot sidewalk. It "wets" the sidewalk. Imagine ice-cream on the same sidewalk on bitter-cold day. It just sits there, barely touching.

Yes, the tip should be wet with solder. You can't heat a round wire with a flat iron; you can't even heat a flat pad with a flat iron all that well. Molten solder fills the space with metal so heat transfers WELL. I don't mean dripping wet, but enough so heat flows good. I generally flood the tip then shake it. (Yes, I have scars on my eyelids; gentle swipe on that brillo-thing is wiser.)

 

[Timh]

Those joints are terrible. You melted the solder and set it on the pad/lead. What you need to do is *heat* the pad and lead, *then* let the solder melt on the pad/lead.

Imagine ice-cream on a hot sidewalk. It "wets" the sidewalk. Imagine ice-cream on the same sidewalk on bitter-cold day. It just sits there, barely touching.

Yes, the tip should be wet with solder. You can't heat a round wire with a flat iron; you can't even heat a flat pad with a flat iron all that well. Molten solder fills the space with metal so heat transfers WELL. I don't mean dripping wet, but enough so heat flows good. I generally flood the tip then shake it. (Yes, I have scars on my eyelids; gentle swipe on that brillo-thing is wiser.)

I already got the whole "heat the lead and melt the solder onto it" I guess I just hold my iron there for too long?

 

[Kingston]

To answer the thread title: almost everything.

Please have a look at some basic soldering tutorials on youtube. Your technique has more than one serious problem.

You really should have practised soldering on something less critical. I would not trust even half of those solder joints in the picture. In fact now you have to clean up the board and start from scratch. Also, desoldering is actually more difficult than plain soldering so now you have some serious learning to do.

You could start from here: http://www.youtube.com/watch?v=J5Sb21qbpEQ

 

[gemini86]

Speaking from my own mistakes, a lot of that has to do with a filthy tip. With a brand new tip, you need to tin the it before use. Just load the thing up with a ton of solder, get it everywhere. Then wipe it with a clean damp sponge. After every few joints I solder, I wipe the burnt up rosin off the tip. It should last a long time if you keep it clean. What's happening to you now is that the tip isn't transferring heat to the pads, it's only melting solder onto the component leads. You may be able to save those solder joints if you dab each one with some solder paste and reflow the joint. Then clean everything with alcohol to remove the paste residue. If you're in a pinch and your tip is all worn out, I've been able to file it to a point again, clean it and re-tin the freshly files tip and it will get you through the rest of what you're doing that night, but not much more. They burn up really quick once the nickel/steel plating is gone.

 

[Timh]

I've already re-soldered some joints that I know are bad. I'll continue to do more tomorrow. Right now I'm just tired and most of all disappointed.

 

[Kingston]

I've already re-soldered some joints that I know are bad. I'll continue to do more tomorrow. Right now I'm just tired and most of all disappointed.

Time for a break then!

Then go buy some vero-board and practice a little. The technique is surprisingly simple, but none of us were born with it. You'll feel great after the "a-ha!" when those joints all start to flow.

 

[jplebre]

Dont' give up. Like kingston said, get a vero, get one of those "maplins" "resistor set" for £.50 and just solder away.
The 51x was a tricky one. Huge coper traces, a lot of heat. I made a few solder joints half heartedly and they were terrible. Because of the heath and the time you have before solder gets "dry" I felt I needed to solder each and every point with confidence.

What sometimes help if I'm in a hurry is a flux dispenser pen, mainly to reflow. May not be the right way, but from my experimentation that's how I got best success in reflowing some odd joints.

 

[thermionic]

I reckon PRR is on the money here. Put another way: hold the hottest part of the tip in the 'corner' point between component lead and PCB (or whatever 2 items you're soldering). The idea is to heat both faces being soldered equally. After a second doing this, then feed the solder against the component faces, not directly into the tip. If you're heating everything correctly, the solder will simply melt against both faces without touching iron tip. Voila!