Soldering Basics >>Please read if new to soldering<<

gassy said:
Had to take some triacs off a Ren24 (wrong ones mixed in the bag) and I've never desoldered before. Went out and got a desolder braid and went at it. The problem/question is, in the process I ended up removing a couple of the solder pads. Is all lost?
Click to expand...

The best method to remove the TO-220 package parts from the board is to first take your solder wick and set it aside until the part is out and use for cleanup. Next get a pair of hemostats. Clamp that to to tab and turn the board upside down hanging the hemostat over the table. Apply solder and heat. Eventually the weight of the hemostat will pull the TRIAC out once the solder becomes liquid and leave the runners and through holes in tack. Now use the solder wick to clean up the holes. Learned that trick over 30yrs ago and have never damaged a board since. It works for most leaded components. If you are industrious you can even place a narrow strip of thin metal under dip packages and clamp the ends with the hemostats and pull out 16 and 20 pin dips also.

All other SMD work I prefer a hotplate. Works like a champ. Though you have only about two minutes or so to get the part on or off the board , then off the hot plate before you start to cook the board. I have very good success with 80 and 100 pin 1mm pitch BGA parts using a hot plate. Even fine pitch BGA parts can be done with a hot plate.

james
 
Hi guys, newbie here. Just getting ready to try soldering my first boards. I've never done this type of soldering before but I have soldered pipes, I guess it's kind of the same principal. Lol

Here's my question...I went down to radio shack to pick up some solder. I saw at the beginning of this thread you were using 63/37. They don't carry that, I picked up a spool of 60/40 rosin-core solder. Is this okay?
 
Javo said:
Hi guys, newbie here. Just getting ready to try soldering my first boards. I've never done this type of soldering before but I have soldered pipes, I guess it's kind of the same principal. Lol

Here's my question...I went down to radio shack to pick up some solder. I saw at the beginning of this thread you were using 63/37. They don't carry that, I picked up a spool of 60/40 rosin-core solder. Is this okay?
Click to expand...

Should be fine. You don't want Lead-Free, it's much harder to work with.

Also, if you haven't soldered before, go to Radio Shack and buy a Perf Board and a thing of cheap parts. Use this to practice soldering. It's a great way to practice
 
Javo said:
Hi guys, newbie here. Just getting ready to try soldering my first boards. I've never done this type of soldering before but I have soldered pipes, I guess it's kind of the same principal. Lol

Here's my question...I went down to radio shack to pick up some solder. I saw at the beginning of this thread you were using 63/37. They don't carry that, I picked up a spool of 60/40 rosin-core solder. Is this okay?
Click to expand...

Yes, 60/40 is just fine.... 63/37 is just better.
 
Thanks for the input gentlemen. I figured I would start with the SSRez's before attempting the 64xc. I did order extra of everything from Mouser so I would have spares due to rookie status.
 
For a beginner, I certainly recommend soldering one whole board first. So complete a single SSR and review. Not a whole lot to mess up, but make sure you have sockets, LED and triacs oriented correctly.
 
Unfortunately I didn't come across the thread discussing the new triacs before I ordered my parts. Mouser didn't have them (the "old" ones) so I ordered them from a company called digi-key. I did see from your posts you haven't had any issues. Hopefully mine will work fine too. Now to figure out how to connect these to my computer.
 
I've done a fair share of soldering and desoldering on PCB boards. I find a solder sucker tool is a must have. I don't know if that is the correct term for it, but thats exactly what it does to hot solder. Sucks it right off the joint. And no mess like when using a braid. My Opinion.
 
IMHO, I actually like this better than my Kester44. I use the MG for fine work and Kester for larger fills. I think the MG flux splatters less and leaves less flux on the board.
 
MichiganLights said:
How well does this "no clean" solder work?

http://www.circuitspecialists.com/4865-227g.html

Is there any difference between no-clean and traditional rosin-core solder? It says none corrosive, so how does it clean the impurities and oxidation off he parts being soldered?
Click to expand...

Pretty much the same way all solders work.

The main purpose of the flux is to react with oxides on the pads and allow the heated solder to become a more uniform liquid prior to heat removal. Thus mix with the base metal , often copper, to form a strong uniform joint.

Ever since the days of freon banned from use, there has been a constant search for the magic solder flux that needs little or no cleaning afterwards. In the past the need to clean after soldering was to remove the flux from the board. This is in part to the fact that the flux residue can trap moisture and holds contaminants. This can lead to dendrite growth and cause issues with high impedance lines. I have seen a huge evolution is agents used to clean the boards after soldering. In the old days the resin flux used was not water soluble. It was only soluble in alcohol. Alcohol mixed with freon was the standard prior to the 80's. The alcohol diluted the flux and the freon allowed the whole mess to be evaporated off the board. Worked well until the patents for freon ran out and then the world got some sort of religion about the use of freon. That is another subject to its own.

In the past several decodes water soluble fluxes have been developed. Some have worked better than others. Today there are steps taken to prevent the boards from oxidizing so much. HASL coatings instead of tin. Even the use of gold plating both acidic placed and catalytic process are used. Copper oxides are not conductive. They are also resistant to heat. The process of soldering is a chemical bond in which a thin layer of the copper surface merges or alloys with the solder to make a strong mechanical connection. What happens when there are oxides on the copper and the flux does not clean that, the joint becomes brittle and weakened. It can over time become resistive. Acid core flux can not be used on PCB materials as the copper is often to thin and the residue flux left on the board is acidic enough to start to play PACMAN on the remaining copper traces. Not a good solution.

Kester made several different reactive fluxes. Almost of the old ones had to have the board cleaned somehow. The Holy Grail is to have a flux that does not need cleaning. Have they really found that? I am not so sure but maybe MG has found the right mixture.

james
 
Its been quite some time since I soldered at the board level. Repairs mostly. On through hole I just solder then clip off the excess lead/wire. Not very professional looking though.:eek:hwell:

What do you guys do to get a clean professional look? Solder & cut, cut & solder, neither?

What do you do with the heavier leads on triacs and larger transistors?
 
Buy a can of cheap 'Brake Parts Cleaner' from Wallyworld (less than $3.00) or any Auto Parts store. Spray the back of the board off real well, it does a great job of cleaning any residue from the board and dries almost immediately. In fact buy two cans, cause you always need more than you think.........:wink:
 
MichiganLights said:
Its been quite some time since I soldered at the board level. Repairs mostly. On through hole I just solder then clip off the excess lead/wire. Not very professional looking though.:eek:hwell:

What do you guys do to get a clean professional look? Solder & cut, cut & solder, neither?

What do you do with the heavier leads on triacs and larger transistors?
Click to expand...

I take the "Solder & Cut" approach.

The cutters I use are "flush cut pliers" like this:
http://www.homecontrols.com/Platinum-Tools-5-Full-Flush-Cut-Side-Cutting-Pliers-PL10531

I then use cleaner like this:
http://www.blowoff.com/cleaners/heavy_duty_parts_cleaner.htm
 
I have another question. I had trouble soldering the center lead on a Voltage regulator. U1 in this picture.

index.php

http://www.doityourselfchristmas.co...e=File:Wiki_-_Renard_SS24_Assembly_Step16.jpg
This is the ground/tab lead. The solder started to flow then went cold quickly. I believe the Voltage regulator absorbed all the heat. So i tried to reheat and it was taking a long time and the VR package was getting extremely hot.

How much heat can these VRs take? What techniques do you use for similar IC's with a heat sink?
 
MichiganLights said:
I have another question. I had trouble soldering the center lead on a Voltage regulator. U1 in this picture.

index.php

http://www.doityourselfchristmas.co...e=File:Wiki_-_Renard_SS24_Assembly_Step16.jpg
This is the ground/tab lead. The solder started to flow then went cold quickly. I believe the Voltage regulator absorbed all the heat. So i tried to reheat and it was taking a long time and the VR package was getting extremely hot.

How much heat can these VRs take? What techniques do you use for similar IC's with a heat sink?
Click to expand...

What heat setting was your iron on? 700ºF is good for those parts.
Sometimes on the tabbed parts, after they cool, a retouch on the top side will give good results.
 
MichiganLights said:
I have another question. I had trouble soldering the center lead on a Voltage regulator. U1 in this picture.

index.php

http://www.doityourselfchristmas.co...e=File:Wiki_-_Renard_SS24_Assembly_Step16.jpg
This is the ground/tab lead. The solder started to flow then went cold quickly. I believe the Voltage regulator absorbed all the heat. So i tried to reheat and it was taking a long time and the VR package was getting extremely hot.

How much heat can these VRs take? What techniques do you use for similar IC's with a heat sink?
Click to expand...

Most leaded parts like a TO220 package can take 700 F for three to five seconds per pin with no ill effects. Preferably a little hotter say 800F. Most will have a maximum of ten seconds for the three leads combined.

Another thing to consider is the wattage of the iron. When soldering, the heat of the iron transfers to the surrounding part and PCB traces. If the iron does not have enough wattage to recover for the loss of heat in this transfer then it will take longer to get a proper solder joint. Not only is temperature important but wattage of the iron is important when soldering large mass parts or where there is a lot of copper on the board that maybe used for heat sinking.

Leaded parts like the regulator and large TO-220 case devices I would not use anything less than a 60W iron. Also not more than a 90W iron either. Also try using a bit of extra flux when soldering with lower wattage irons. This will help the solder to become liquid quicker and reduce the total soldering time. Sometimes thin lead solders just do not have enough flux within the core to be sufficient with large mass devices.

Remember in soldering Flux is your friend. You can always use alcohol to clean the boards afterwards.

james

james
 
I'm running a 65W iron at 675 F.

I don't recall ever getting a package that hot before, it made me nervous.

Thanks for the pointers.
 
Clean or "no clean" solder for your choice?

I haven't had the need to purchase new solder in a while and came across this "no clean" stuff. Any inputs on this?
 
I like using a small chisel tip either .8mm or 1.2mm. For voltage regulators, triacs, ect.. I stand the tip up so the the end is on the pcb pad and the side of the tip is along the leg being soldered, this allows a lot of the heated surface of the tip to be directly in contact with the part being soldered. Two to three seconds will usually suffice. I am using a Tenma 60W digital station at 685 degrees.
 
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