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onebuck 07-02-2012 08:04 AM

Hardware hacker wanna be then you will need to know how to solder.
 
Hi,

For new or old hardware hacks then you must know how to properly solder. Full Solder Comic is a simple but useful guide to get you started.

Remember practice, then practice some more and be sure to be safe. :)

Soadyheid 07-02-2012 09:15 AM

Did you find this on the Raspberry Pi web site? ('Cos it's there as well!)

Over here in the EU we're being tied to RoHS (Pronounced "ROSH" and meaning Restriction of Hazardous Substances Directive) which was put in force on the 1st July 2006 which, unfortunately, prevents the use of resin (rosin) cored solder so it's nigh impossible to get hold of here. Note the "Don't breath in the fumes" comments from the Icelandic guys who wrote the comic.

I spent three weeks of my apprenticeship back in the late sixties learning to solder and have to say that non-lead based solder is definately not as easy to use. I have great difficulty getting the solder to "wet" the component lead and pad to give a good joint. The magic marker style flux needed to do the job of the resin (rosin) doesn't seem to be as efficient. Then again... Maybe it's me. :)

Play Bonny! :hattip:

onebuck 07-02-2012 10:44 AM

Member Response
 
Hi,

I think it was from the Pi pages originally.

I made bulk purchases of micro rosin core lead a few years ago. One # spools and enough to last me years of projects. You can use a fan to blow the fumes away/collect them through a filter box with a fan drawing the fumes. Depending on the job, I tend to rely on third hand devices to aid when soldering. One set to hold the board and another to hold or heat sink the device being soldered. Surface mount devices are a different animal. :)

Most school systems in our area have dropped shop classes. Some project classes do offer elementary sessions for electronic device handling and builds. Local manufactures are sponsoring mini-robotic academic based competition so some are learning techniques via experienced mentors. This is a win-win for everyone. Advanced education does need to address issues now but it would be best if elementary-secondary provide some hands on or develop interest in these type of learning sessions. Motor skills, hand eye coordination are important when mechanically doing something. This can be taught and improved with practice. As they say: 'Practice makes perfect' or: A tool is but the extension of a man's hand and a machine is but a complex tool. He that invents a machine augments the power of man and the well being of mankind.” - Henry Ward Beecher

Today everyone wants to play games and not really desire to know the underlying operations be it electronic/mathematical or graphical operations. Everyone tends to think that games build or development are the demand. I think otherwise. I am not saying everyone should know how the systems are built but system builds/electronic interfacing are becoming a lost art. Heck, some of my projects still evolve from wire-wrap & perf. Others may come from a breadboard before even consider of a proto-board. Really depends on the complexity of design and the frequency spectrum for the devices on which technique is to be used for proto-board or circuit.

As to your difficulty with non-lead; Be sure the device leads are clean and the pads have been buffed. Sure the job of resin is both isolation of the solder joint and cleaning of the two contact joints thus allowing a good electrical bond between the pad and device lead. Placement of the tip & proper tip type can be a problem for some. Then where you place the solder in respect to tip & joint is very important. Good iron is very important. I use a closed loop temp controlled pencil iron. Keep your tip clean!

Recently I needed to repair a CMS for my Yamaha Venture motorcycle. I could tell that the circuit hand been partially wet soldered and hand soldered for spot jobs. Molex board mount receptacle pads had broken joints(known problem for the 1983). Just sucked all of the pads for the connector(one row at a time to prevent creep). Rosin joints had to be cleaned thoroughly for some of the discreet components. Surprised the problem had not occurred earlier. This repair was a real challenge, even for me. Reasoned the type of solder was the main point to remove the old solder completely instead of wetting again with a repair joint. Best to remove the old solder completely then re-solder. Successful!

EDDY1 07-02-2012 10:45 PM

Great comic onebuck, you brought this out right on time.
My acer aspire 3620 dcjack went bad & I recieved the new part a couple of days ago. I went shopping for soldering supplies today, but aborted mission.
Was trying to ask the guy at radioshack which iron 15 or 30 watt was best for pcboard he was too busy.
1.Which iron 15 or 30 watt ?
2.Is flux necessary?
3.What size or guage of wire?
Thank You in advance. I miss my acer.

brianL 07-03-2012 03:55 AM

I spent quite a lot of my working years soldering, so this quote from that comic explains everything:
Quote:

If you don’t wash your hands after soldering, the lead may
get in your body, where it gets stored in your brain
for your entire life. if enough collects there then you
go insane, and you lose all of your friends.
:D

onebuck 07-03-2012 07:41 AM

Member Response
 
Hi,

Quote:

Originally Posted by EDDY1 (Post 4717725)
Great comic onebuck, you brought this out right on time.
My acer aspire 3620 dcjack went bad & I recieved the new part a couple of days ago. I went shopping for soldering supplies today, but aborted mission.
Was trying to ask the guy at radioshack which iron 15 or 30 watt was best for pcboard he was too busy.
1.Which iron 15 or 30 watt ?
2.Is flux necessary?
3.What size or guage of wire?
Thank You in advance. I miss my acer.

For an experienced user a 30W pencil iron with a clad thin chisel tip for components. A clad thin pointed tip is best for DIP/Transistor joints. You should use a heat sink for DIP/Transistor work. You will be using resin core solder, additional flux is not always necessary unless the solder is a alloy then additional flux can sometimes be a good thing. You can get flux in a marker type applicator or paste. If the pads are clean then the resin cored solder should be enough. As to the wire size/gauge, are you speaking of interconnection? If so then short lengths of 24 AWG wire wrap wire can be used. If you are speaking of the solder diameter, it will depend on the soldering job at hand.

For general component, discreet & integrated parts I will use 21 AWG(.031 Dia) single core resin 40/60(you can get multi-core at more $$). Even smaller gauge for flat pack/surface mount (SMD). If the task is new then I will use a smaller gauge solder with more heat so that my solder time is cut short. Experience will dictate your soldering time for each task, as you get better at the task then your time can become shorter. Be very careful since you can make cold joints or resin joints if you do not use enough time for heat. That is one reason to have temperature controlled pencil iron(closed loop), once you set the temp then the tip will remain at a constant temperature when out of the cradle.

If you need to solder discreet active components (transistors, DIP or like) then be sure to use quality heat sinks. For transistor I will use hemostats or alligator clips. DIPs', I have sinks for each DIP series size that I custom made. I use these to insure no possible damage to very expensive DIP. At the time these were very expensive so I used a Mill to make a set. Some will use a DIP test clip but these really do not have enough sink. Most times I will not heat sink general DIP chips since the single pin heat requirement should not damage the substrate with single pin heat application. You can look at the data sheet for each DIP/series for heat limits for flow soldering which can be a good indicator.

I do purchase refurbished/used surgical tools that suit my soldering jobs; tweezers, hemostats(many type) straight & angled(locking/free clip),scalpels of all type, Dental tools: picks, probes & points.

Please remember that your soldering task does include cleanup. You can purchase board cleaners in liquid or spray. I use alcohol with a fine toothbrush(this can be used to prep for the soldering task). If you choose denatured alcohol then test a board area on outside edges to see if the mask will be harmed. If not then proceed to remove resin.

Most important cleanup is yourself. Wash your hands and exposed areas especially if you choose to use lead based solder. Even with alloy you can experience respiratory issues if you do not use a fan/filter box. If your repair board is older then you will be reheating lead based solder so be sure to use caution & good cleanup. Also remember here that the older solder should be removed. Do not mix alloy & lead joints.

Inspection of the board after soldering is important. You can use a magnifier to inspect for shorts created while soldering or shorts between pads or leads. Solder beads can cause issues if not removed. I use a lighted magnifier and dental picks to probe the areas in question.

REMEMBER: Safety first, so use those goggles/safety glasses. I have been splattered many, many times and my glasses saved the eyes from damage.

Few more useful links;
http://www.sparkfun.com/commerce/tut...s_id=36&page=1

http://www.infidigm.net/articles/solder/

http://www.aaroncake.net/electronics/solder.htm

http://www.kpsec.freeuk.com/solder.htm

http://www.instructables.com/id/How-to-solder/

HTH!

EDDY1 07-03-2012 08:03 AM

Last but not least how can you tell if they used lead instead of lead-free solder?

onebuck 07-03-2012 08:47 AM

Member Response
 
Hi,
Quote:

Originally Posted by EDDY1 (Post 4718070)
Last but not least how can you tell if they used lead instead of lead-free solder?

Visually, not always possible, sometimes the slow cool of alloy will be a dull color instead of shiny but that too depends on the alloy type. Early use for alloy solder was pre-tinning a PCB for wave soldering since the alloy melting temperature was high and cooling slow. Of course, again the alloy type will dictate here.

If you re-heat a test joint then the melting point for tin-lead is lower than solder-alloy. Experience will allow you to identify types. Again, you can use manufacture references to identify. 'MSDS' can/should provide this data.

You can sometimes use the manufacture dates on the PCB to potentially identify solder type if the 'MSDS' is not available. I believe the turning point was in the early to mid 80s'. Testing 'alloy' started in the early 70s'. Some advantages for 'alloy solder' is the higher melting point. Most consumer products do use 'alloy(Sn60, ASTM60A, ASTM60B)' or for common electronics uses then 'alloy' (Sn63, ASTM63A, ASTM63B) to meet industry standards to have lead free products. I really do not know of too many people who put a PCB in their mouth but 'Stupid is as stupid does'. Boy, I love that movie!
Really the problem is if the device fails and the joints melt then producing gasses that are potential carriers.

"Life's tough...It's even tougher if you're stupid." - John Wayne

HTH!

jefro 07-03-2012 11:15 AM

The fumes of heated lead and lead-free solder can also be a health issue. Glad it was posted to wear safety glasses above. Assume all controls are to be used. The device you are soldering to may have lead. Again lead free isn't safe to breath or eat either.

Surprised they didn't offer correct soldering iron temperature ranges. More heat is not better.

EDDY1 07-03-2012 07:14 PM

My radio shack soldering iron 15-30 watts would not heat up joints on the circuit board enough to remove but it does melt solder that's from the spool.

jefro 07-03-2012 07:29 PM

That is why a better soldering station is used by people who do this for a living. They don't rely on watts, they rely on both their training and the stations ability to set temperatures for the task.
Simple things can also reduce the heat at the tip. I had to solder a wire in the middle of winter on top of a ship in Japan. I never could get enough heat to melt the solder as it was so cold outside and the wind was blowing like 50MPH. I guess extension cord also played a part but I tested it before I climbed the mast. Darn shame I had to do that in the PI. It was warm enough there.

towheedm 07-03-2012 10:08 PM

Quote:

Originally Posted by Soadyheid (Post 4717143)
I spent three weeks of my apprenticeship back in the late sixties learning to solder and have to say that non-lead based solder is definately not as easy to use. I have great difficulty getting the solder to "wet" the component lead and pad to give a good joint. The magic marker style flux needed to do the job of the resin (rosin) doesn't seem to be as efficient. Then again... Maybe it's me. :)

Lead-free solder is best done in an oxygen free environment. The lead-free solder tends to oxidize much faster than the lead-based solder. This is what causes the 'wetting' issue.

From a training video I saw from PACE, their lead-free solder rework stations has a small built-in nitrogen generator that generates the nitrogen gas from the surrounding air. The gas is applied over the joint to be soldered via a small nozzle in close proximity to the solder tip. This displaces the air and prevents the oxidation problem. This elimimates or greatly reduces the problem of proper wetting during the soldering process.

This is in no way an endorsement of, or an advertisement for PACE, but IMHO, they make the best damn solder rework stations around. And I've used quite a few others over the last 30 years or so.

EDDY1 07-04-2012 06:25 PM

I ended up taking the other soldering iron back & getting a 40 watt got the part off now I just have to cleanup some of the solder in the holes & put the new part on.

Soadyheid 07-05-2012 03:42 AM

Quote:

Lead-free solder is best done in an oxygen free environment.
Wow! There's one for the Health and Safety Directorate! Either you use the old multicore resin (rosin) solder which works great but may possibly cause you to die a horrible death from inhaling the fumes, or you use leadless solder in an oxygen free environment and risk a horrible death from asphyxiation!! :D
The Whole World's gone mad!

Play Bonny! :hattip:

onebuck 07-05-2012 09:00 PM

Member Response
 
Hi,

Quote:

Originally Posted by EDDY1 (Post 4719437)
I ended up taking the other soldering iron back & getting a 40 watt got the part off now I just have to cleanup some of the solder in the holes & put the new part on.

You can use a SolderPult from Radio Shack. Simple device that creates a vacuum via a plunger that is spring loaded. You reheat to wet the solder for component or through hole then when you place the solderpult on the opposite side of the reheated hole, you activate the solderpult via the trigger then the hole is cleared. Same for a component lead. If you are wanting to change a DIP then use a micro-snip to cut each lead then reheat the pin with the solderpult over the pin then active so the solder and pin are sucked into the cylinder.

HTH!


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