Tools and Equipment
Board level repair is not an easy job. To do it without the proper tools is even harder. In the article below, I’m going to detail all of the tools and equipment that you’ll need to get started.
The definition of microsoldering is being able to solder through a microscope because the components are so small that they’re almost impossible to see without one. Just to get an idea of how small these components are, here is a chart of the surface mount components commonly found in iPhones and iPads:
In the schematics, you’ll see each component identified along with their size, similar to this:
For FL25, which is a filter (inductor), you can see that the component size is 01005 (displayed at the bottom). Looking at the wikipedia chart above, under “imperial code”, you can see that that this is the smallest surface mount component made. The black rectangles in the size chart above is the actual size of the component, so now you can see how trying to solder one of these components on a logic board is nearly impossible without a good microscope.
So, what do you need to know about buying a microscope? Do you need a barlow lens, a boom stand, an objective lens, 2x/4x, trinocular, simultanous focus, etc? Unless you already own a microscope, it’s so overwhelming trying to figure out what you actually need for smartphone and tablet repair.
You’re in luck because I’m going to help you with deciphering the different kinds of microscopes used for microsoldering.
To cut to the chase, here is the microscope that I recommend:
I would definitely stick to Amscope. It’s best to buy it through Amazon. The 0.5x barlow lens will give you a greater working distance between the scope head and your workbench.
The 0.7x-4.5x zoom objective will allow you to zoom way into the logic board, so that you can see what you’re soldering. This zoom objective is standard for pretty much all microscope heads. The eyepieces and the barlow lens is what changes the magnification from 0.7x to 0.35x (0.5x barlow) or from 4.5x to 9x (2x barlow).
The trinocular port will allow you to record videos through the third eyepiece. And the most important thing is the simultaneous focus, which will allow you to see through both eyepieces AND record video through the trinocular port without closing off one eyepiece. Without simul-focus, you’ll only be able to see out of one eyepiece while recording video. The above scope doesn’t come with a digital camera or a light ring, but you can get a cheap light ring on ebay for around $10-$20. I would definitely recommend getting a light source when you order the scope.
Here are some other alternatives:
- AmScope SE400-Z – $184 (I think you’ll regret buying this one)
- AmScope SM-3BX-80S – $399 (same as above without the trinocular port)
- AmScope SM-4TX – $419 (same as the above, but without simul-focus)
- AmScope SM-4TPZ-FRL-5M – $699 (same as above, but comes with a 5MP camera and a light source)
- Search for Amscope Professional Trinocular Simultaneous Focus Microscope at Amazon Warehouse
- Search for Amscope Professional Trinocular Simultaneous Focus Microscope at Amazon
Soldering Rework Station
Every microsolderer needs a good rework station. What’s a rework station? A rework station usually comprises of at least a soldering iron and a hot air gun. You can buy a cheap X-tronic or Aoyue hot air station on amazon, but I think the way to go would be a good Hakko. They’re not too crazy expensive, they work a lot better and they tend to last a lot longer than the cheaper alternatives. I would also recommend buying separate stations for your soldering iron and your hot air. The stations that are combined tend not to work as well. You’ll probably want to add a good microsoldering pencil or micro-tweezers after you get the rework station. This will help with the extra small 0201 and 01005 smd components.
Without further ado, here are my recommendations for a good rework station:
Personal Note: Best hot air rework station that I’ve had.
These are the soldering equipment that I recommend, but I know price may be a factor, so here are some alternatives.
Hot Air Stations
- JBC Tools JT-1QD Hot Air Station – $1,300 (I can’t get myself to spend this much on a hot air station, but this is the one that I would get if it made sense.)
- Kohree Hot Air Station – $59 (I’ve never used this, but great reviews on Amazon)
- Weller WHA900 – $720 (Still crazy expensive for hot air)
- Oki/Metcal HCT-900-11 – $637 (look for a used one on ebay.)
- Quick 957DW+ – $120 (I have one. It’s good, but I would spend a little extra to get the Quick 861DW because that one has 3 programmed channels. The good thing about this station is that it works with the Aoyue and Hakko tips.)
- JBC Soldering Tools NASE-1B – $1,300 (This is what I use. If you have the budget, then don’t look any further.)
- Hakko FM-202 – $100 (Can only buy used – works with FM-2032 pencil…BEST for the price)
- Hakko FX-951 – $236 (Doesn’t work with the micro-tweezers though)
- Aoyue 937+ Digital Soldering Station – $60 (Great heat distribution.)
- Hakko FX-100 Induction Microsoldering Station– $299 (never used)
A digital multimeter is essential for logic board repair. You don’t really need anything fancy, since most of what you’ll be dealing with is low voltage (~5V) and you’ll be testing for continuity, diode mode, resistance, voltage, and sometimes capacitance. Sure you can get one of those awesome, but expensive Fluke multimeters:
But the truth is, it’s probably overkill for microsoldering. Personally, I use the Uni-T UT60G. It costs around $60-$70 at Amazon or Aliexpress and it has pretty much every feature that you’ll ever need for microsoldering. The bonus about the UT60G is that it also comes with a thermocouple which measures temperature. I use this to calibrate my hot air rework station. Other than that, it’s just like any other digital multimeter and it’s fairly accurate.
ZXW Tools Dongle
This piece of software tells you what each component is connected to on the logic board. In a way, it’s better than schematics because with the schematics, you still don’t know where each connection is made on the logic board. For example, the backlight on an iPhone 6 went out, but it’s not the backlight filter, so what component is next after the filter?
You can search the schematics for what’s next in line, then go back up to the top where the drawings are located, but that’ll take forever when working in real life. With ZXW Tools dongle, you can see what component is next in line very quickly.
We sell the dongle in our online store. The dongle is just a security key that allows the downloadable software to work. The software is updated automatically via the internet with the latest iPhones versions. But the dongle only works for a year before the subscription will need to be renewed. This tool is essential for iPhone repair though.
Solder, Flux, Isopropyl Alcohol, etc.
Now that you have your microscope and a good soldering rework station, the next step is to buy some solder, maybe some solder paste, some good flux, and a jug of isopropyl alcohol. This could also be a little overwhelming because there are so many different types of solder and fluxes.
For solder, most newer devices use lead-free solder, which have a much higher melting point. The higher the melting point, the harder the solder is to work with. For most microsolderers, we replace the lead-free solder with leaded solder when we’re replacing smd components.
I stole this chart from Kester (big company that produces solder):
As you can see from the chart, lead-free solder melts at roughly 220 °C and leaded solder melts at 183°C and higher. “Sn” is tin and “Pb” is lead. The standard solder that most microsolders use is Sn60Pb40, which is 60% tin and 40% lead. How much solder will you actually need as a microsolder? Very little. Depending on your volume, one little stick will probably last you a good while. This Kester 60/40 0.031 diameter stick costs $6.
In addition to some 60/40 leaded solder, you’ll probably want something to help you remove existing chips, like Chipquik. Chipquik is a low melt solder that melts at 58°C. Using Chipquik allows you to remove existing chips without applying too much heat to the surrounding components. The way it works is that you apply a little bit to the end of your soldering iron, then mix it into the solder on the component, which lowers the melting temperature of whatever solder is already on it, usually lead-free solder. Once the melting temperature is lowered, then it’ll be a lot easier to remove the component from the board.
Or you can use the higher melting (138˚C) low melt solder paste.
Flux, what is flux? Flux is a yellow like substance that helps the solder flow onto the smd components more easily. Think of flux like this…if you put oil in water, the oil won’t mix very well, but if you add a little bit of detergent (flux),then the oil and water will eventually mix together. Flux is necessary for making a good strong solder joint. It helps the solder flow onto the smd component.
There are many different kinds of flux. My favorite? The Amtech NC-559-TF. Make sure that you buy from a reputable ebay dealer or online shop because there are a lot of fakes out there. A 10CC tube should cost about $15 and 30CC should cost about $25. Anything less that ships from China is probably not the real stuff.
One 10cc tube should last you a long while depending on your volume. There are a few ebay sellers that sell them as well.
Here’s a chart from Amtech that kinda describes all of the different kinds of flux:
What is solder paste? Solder paste is essentially liquid solder in the form of little balls.
Solder paste comes in the form of a tube and comes mixed with flux. Solder paste is great for instances where it’s easier to use a hot air gun than a microsoldering pencil or micro tweezers. For instance, pry damage near the battery connector on an iphone 5. It’s almost impossible to access the 01005 filter with anything but a hot air gun and some solder paste.
Solder paste is also good for removing chips or connectors due to it’s low melting point. The low melt solder paste above melts at 138°C — much less than leaded solder, but not as low as Chipquik. The idea is the spread the low melt solder paste on the legs of the connector to reduce the melting temperature of the lead-free solder, so that it’s easier to remove the connector with hot air. SRA low melt solder paste does the job. I prefer Mechanic brand low melt solder paste though.
A bottle of solder mask might be a good idea to have on hand. Solder mask is a glue like substance that turns solid, just like glue, once it’s introduced to the surrounding air. For microsoldering, sometimes it’s useful to put a “mask” around the surrounding small components, so that they don’t burn or move when you’re removing a component. The solder mask protects the surrounding components from the heat.
Here’s the stuff that I use:
You’ll also want a mini duster/blower. This high powered blower will help you get rid of the isopropyl alcohol much faster. It’ll replace the canned air that you can also use, but this will last forever.
Some other random things that you’ll probably want to have on hand:
That’s about all for now. You’ll acquire a bunch of things along the way. Some useful and some not so much. Don’t forget to buy some good tips for your soldering iron, maybe some tip tinner, and maybe a smoke absorber for the solder fumes. Good luck!
You’ll need some isopropyl alcohol too. Preferably something with 91% alcohol or higher. Isopropyl alcohol is used to help dissolve the flux, so that you can scrub it off of the logic board or wipe it off with a KimWipe. It is alcohol, so it evaporates. It’ll also help you clean off the logic board without leaving a corrosive element like water. You can buy a bottle at your local walmart or computer store (Microcenter) or at Amazon.