Hakko 936 users

[seanohue]

What tip do you use for SSIP stuff? I'm talking about the real small pins, thinner than the ones on most op amps (like the pins you would see on a DAC chip). The tip # would be really helpful too

 

[n_maher]

Rather than change tip sizes you could try the "flood and suck" method. Check the Alien DAC construction thread, I'm pretty sure there's a link there for it. In my experience there is no tip/solder combination that will allow easy soldering of DAC chips.

 

[AndrewFischer]

900-M-T-0.8D

Plato HS-2863

 

[DaKi][er]

The size doesn't matter much at all, you do not want to be soldering individual pins on an SSOP SMD.

Mentioned is the "flood and suck" where you flood all the pins with solder and then suck away all the excess which does work quite well, but what I think is a far better method is the "paste and draw' where you tack 2 corners of the chip down on the pads and then paste the thing in flux paste and then wipe the iron along the edge of the pins and the solder that is already coating the PCB pads will flow into the pins

I've used both methods and the paste and draw produces far better and professional looking job with very little effort

 

[seanohue]

I cant use flood and suck because I will be modifiying a chip on a PCB that has already been soldered so I will be needing to do precision soldering this time.

 

[DaKi][er]

Quote:

Originally Posted by seanohue /img/forum/go_quote.gif I cant use flood and suck because I will be modifiying a chip on a PCB that has already been soldered so I will be needing to do precision soldering this time.

Modify in what way?

 

[SiBurning]

How are your eyes and hands? I have a lighted magnifier to make it easier to see small parts, solder bridges, etc. My hand's really shaky.

What I'm getting at is you should practice on some spare cheap parts before doing surgery.

Then the only problem is getting stuff to practice on. Any ideas?

 

[seanohue]

Quote:

Originally Posted by DaKi][er /img/forum/go_quote.gif Modify in what way?

Attach 30ga wires to the pins of the SSIP chip.

I got plenty of stuff to practice on, I just need a tip that will give me a good margin of error.

 

[splaz]

I just used a 0.5mm conical. I also have a 0.2mm conical and a 0.5mm bevelled long reach tip that goes to a very fine needle like point.

I didn't use the last 2 as they were ineffective for heating up the ground plane and I found the flood and suck method to work best.

I do use the smaller ones though not as often, the very fine tip I use for wiping out bits of solder between pins etc.

I had to attach a small wire to jumper a pin to the track after the pad err... went for a walk.

Just used the 0.5mm tip. Tinned the wire, held it onto the pin and heated it up.

 

[SiBurning]

Quote:

Originally Posted by splaz /img/forum/go_quote.gif Just used the 0.5mm tip. Tinned the wire, held it onto the pin and heated it up.

Makes sense. If you tin the wire, then all you need to worry about is whether the wire itself is touching only the pin you want. You could use one of those 1/2" wide flat irons and not care.

 

[mono]

Agreed, but it wouldn't hurt to first take a swap w/alcohol and clean off the pin then put a tad of flux on it.

 

[Sinbios]

Personally, I don't like the flood and suck method because it's too easy to screw up and leave the entire row of pins bridged, or have pins with too much solder sucked away. I like the paste and draw method much better, since it guarantees a solid connection and is super easy with some flux. For that you'd need a smallish chisel tip, so you can wipe the flat side over the pins.

 

[seanohue]

Hmm I'm having a real tough time with this. I think proper heat levels may make this easier. I'm trying to solder 30ga wires to the pins on a chip and I keep making bridges between the pins. I don't want to kill the chip on the board that I am working on because, well, its going to be expensive if I mess up. What can I try to do this more effectively? Temp ranges, tips, techniques, etc all help.

 

[mono]

It's hard to say without seeing the technique but I would wonder if you had the wire tinned already (do), and if using too much solder, not enough flux. If you are trying to hold the wire still in your hand while soldering, try tacking it down first.

 

[beerguy0]

Quote:

Originally Posted by seanohue /img/forum/go_quote.gif Hmm I'm having a real tough time with this. I think proper heat levels may make this easier. I'm trying to solder 30ga wires to the pins on a chip and I keep making bridges between the pins. I don't want to kill the chip on the board that I am working on because, well, its going to be expensive if I mess up. What can I try to do this more effectively? Temp ranges, tips, techniques, etc all help.

I do this all the time at work, even on QFP packages. Magnification helps a lot (I work under a microscope - I'd never be able to do this without it). The method I use it to lightly tin both the wire (usually 30 AGW Kynar)and the pin I'm soldering the wire to. Add a tiny dab of flux on the pin, and with a small chisel tip (700F Metcal, or set your temp to 700 or so), hold the wire to the pin and just touch it with the iron. The flux should let it solder almost instantly. Easy on the solder - too much solder and you'll get solder bridges. Get some .015 or even .010 solder. Those are my two most used solder diameters, but 99% of my soldering on the job is SMD, usually 0402 or 0603 components.

The 900-M-T-0.8D is one of my favorite tips for the Hakko. I find the chisel point tips to be much more useful than the narrow conical tips. The really skinny tips don't have enough thermal mass to transfer heat well, and you have to stay on the joint for too long. I use Metcal irons at work, but I have my old Hakko 928 at home.