Soldering

26

9

submitted 1 year ago* (last edited 1 year ago) by [email protected] to c/[email protected]

0 comments fedilink

A pair of friends, brothers, own a small business manufacturing custom PCBs and systems. The older of the two has always done all of the hardware and the younger the software. The older brother had a heart attack several years ago and has had a shake and weakness in his right hand ever since. He can no longer solder small components so I have taken over that function for him. I love soldering and I love the challenge.

This is a PIC microcontroller that I soldered onto a breakout board for them. It's a 0.5mm pitch (0.5 mm from the center of one pin to the center of another pin) TQFP package. I used a Weller WESD51 soldering station with a PES51 soldering pen and an ETGW angled, cupped soldering tip.

I do all of my fine soldering under an Olympus SZ40 binocular microscope that I bought for $200 a couple of years ago from a microscope shop in Montreal.

27

14

HOW TO: Hardware debounced tact switch for solderless breadboards. (lemmy.ca)

submitted 1 year ago* (last edited 1 year ago) by [email protected] to c/[email protected]

0 comments fedilink

Yesterday I posted a picture of a little tact switch that I installed on a piece of protoboard with a hardware debounce circuit on the bottom. I love those little things and thought I would share a how to for making them.

The first thing you need is the little piece of PCB. I had a bunch of these Altoids Tin protoboards made up a few years ago.

Full

I break them down into smaller pieces,

Full

then I break those down to the size that I need,

Full

then I sand the edges to make them pretty (and also to make them small enough to sit beside each other if I need more than one.

Full

Note that the board consists of four columns of 3 connected pads and four columns of 2 connected pins.

Next, I assemble (almost) all of the components that I'm going to need. These are (top to bottom, left to right) 1 uF 0804 capacitors, 1 K 0804 resistors, and 10 K 0804 resistors, the little sanded piece of PCB, three r-pin pieces of header strip (I like to use one red, one blue, and one black but you can use all black or any other color you want), and a 5 mm x 5 mm tact switch (I like the ones with the 7 mm shaft as shown because I can put a cap on them but any old tact switch will do.) Missing from this picture is a

Full

First, we're going to install the debounce components on the bottom of the board. With the columns of 2 at the top and the columns of 3 at the bottom you're going to bridge the gap on the second column with the little jumper wire and the third column with the 10 K resistor. Next you're going to bridge the top end (at the 2-pin column side) of the little wire and the 10 K resistor with the 1 uF capacitor. Finally, you're going to bridge the bottom of the right two 2-pin columns from the pint where the 1 uF capacitor and 10 K resistor meet to the bottom of the last column leaving the hole unobstructed. It will look like this:

Full

The next part is tricky. You have to push some of the pins on the header strips through. On the black one and the red one (or two of the black ones) you're going to push three of the pins through from the long side. On the blue one you're going to push through one of the pins from the long side as shown.

Full

Now, push the header strips into a breadboard as shown. The pins that you pushed through do not go into the breadboard, they stick up into the air. It's important that the pins that you didn't push through on the red and black strips line up with the one that you did push through on the blue strip as shown.

Full

Next, put the PCB over the pins as shown. The soldered components should be on the bottom of the board facing the breadboard. Make sure that the point where the capacitor and two resistors meet is in line with the three special pins on the header strips. If thy don't you can turn all of the header strips around and try again.

Full

Next, clip the pins you pushed through, the ones stick up into the air, off flush with the PCB.

Full

Now, push the ends of the short pins you didn't push through and cut off down flush with the surface of the PCB.

Full

Check one more time that the three special pins and the point where the three components meet are lined up then solder the pins marked with an X.

Full

Now, grab your tact switch. Note that the legs have bumps in them to help hold them in the holes while you solder them.

Full

Use a pair of smooth jawed plyers to squeeze the legs straight then bend two pins out at 90 degree angles as shown.

Full

Trim off the ends of the pins you bent.

Full

Insert the tack switch into the PCB as shown. The bent pins will be over the two pins in the blue row that you didn't solder above. You will need to bend the bent pins out a bit to make them reach the middle of the pads.

Full

Now, solder all four pins pushing down on the body of the switch to make sure it's tight to the PCB and lined up square to the board.

Once you've soldered the switch in place flip it over and make sure that there is a good connection between the end of the 1 K resistor and the pin of the switch. Add a bit of solder if you need to.

Full

Now you can plug the switch into your breadboard and add a Dupont wire or jumper wire to the pin of your MCU.

Full

Note that the red header strip and blue header strip match up with the red and blue rails on the breadboard. This switch can only be installed on this side of the breadboard to get a debounced going low switch. The construction of a switch for the other side of the breadboard is exactly the same but you switch the position of the red and blue header strips.

This is what one of these little switches looks like in a project. This is a prototype for a ROM switching and RESET circuit I'm going to build into a 23xx to 27256 ROM adapter for the Commodore 64.

Full

28

15

Debounced Breadboard Switches (lemmy.ca)

submitted 1 year ago by [email protected] to c/[email protected]

2 comments fedilink

This is a cool little project. I often prototype circuits on solderless breadboards. I've mostly switched to using 0805 SMD resistors and capacitors. I have a box of 1/4W 1% and a box of 1/2W 1% THT resistors but they aren't neat when they're plugged into the breadboard. I've got 0.1uF capacitors but no 1.0uF in THT.

I decided to make up these little tact switches ready to plug into the breadboard with built in hardware debounce. The debounce circuit also provides a pull-up resistor.

Each switch has a 10K 0805 resistor between Vcc and the MCU pin, a 1.0uF 0805 capacitor between GND and the MCU pin, and a 1K resistor between the switch and the MCU pin. The end result is a nicely debounced going low switch with a built in pull-up. They work great and I can just grab one when I need one and plug it in. I've made versions that will plug into one side or the other of the breadboard so that I can have a switch on either side depending on what works best.

The row with 3 pins is GND and the adjacent row with 1 pin is Vcc. The single pin at the other end is the debounced switched output to the MCU pin.

If anyone's interested I can post pictures of the process of making these and how I wire them up so that the work correctly.

29

79

A repair that I did for a local gentleman recently. (lemmy.ca)

submitted 1 year ago* (last edited 1 year ago) by [email protected] to c/[email protected]

8 comments fedilink

I have an ad up on Kijiji saying that I will do electronic repairs. A local gentleman contacted me and said that he had an air hockey table that he had bought that had a broken connector on the controller board. I said I would take a look. I visited him and found that he was in his 80's.

When I opened the controller this is what I found.

I assumed that he probably had the table for his kids or more likely grandkids to play when they visited.

Some super glue, a bunch of scraping, some small pieces of wire, and some careful soldering later and he's back in business.

It turns out that he and his wife play air hockey from time to time.

30

15

Soldering Tools and Materials from Beginner to Advanced (Part 3) (lemmy.ca)

submitted 1 year ago* (last edited 1 year ago) by [email protected] to c/[email protected]

5 comments fedilink

#Soldering Tools

Most soldering iron manufacturers make some sort of soldering tools or soldering aids. They are an assortment of little pokers and hooks and forks and pry tools. I've looked at them from time to time but all I've ever used are the little plastic things that come with Weller consumer soldering irons.

I love these things. They used to have a fork on one end but I find the poker MUCH more useful so I just sanded a blunt one on one end and sharpened the one on the other end. I always have one near and often in my left hand when I'm soldering. I use them to position small components and hold them while I'm soldering them. I push and pry and poke things with them. I like them so much that I reached out to Weller about buying more. They don't sell them individually but sent me a few in the mail. Awesome customer support!

#Scalpel

The only other thing that I can think of that's part of my tools and materials is a pair of scalpel handles and blades.

This is a No. 3 handle with a No. 11 blade and a No. 4 handle with a No. 22 blade. I use these for all kinds of cutting and scraping operations. I use them for placing stickers and cutting header strips. They are an invaluable tool. You can buy plastic scalpel handles for $1. These stainless steel surgical handles are less than $10 each. The blades you can buy expired in boxes of 50 or 100 for a very reasonable price. You can even cut thin copper wire with these blades.

I think that's everything for now. I might think of something else later and come back and add it. I'll pin this post to the community.

Comments, additions, and questions are welcome.

I remembered another thing!

#Pinchy Things

I have a drawer labelled "TOOLS" and a drawer labelled "PLIERS". Anything scissor like goes in the PLIERS drawer.

In this picture from left to right are:

Flush cutting pliers. They're like side cutters or diagonal cutters but they are ground on one side only so you can cut really, REALLY close to the board. The blades are normally fairly soft so you can only cut soft things like copper wires and component leads. You can buy REALLY expensive ones but these are cheap, house brand ones that I buy at Princess Auto three or four at a time. Seriously, I have like 12 pairs. There are 3 pairs in my PLIERS drawer right now. Next are cabling scissors. They look like hell but they are amazing. One blade is serrated so that wires don't slip out as you cut them. They're tough as well and can cut through anything short of a nail (though they will cut through some small nails.) Next is a pair of little scissors that I use for cutting labels and things of that type. Tweezers are important for handling small components. I have a stainless steel pair, a squeeze open stainless steel pair, and a ESD safe coated stainless steel pair. The squeeze open ones are awesome because you squeeze them open and the spring closed. You can use them to hold wires or small components while you solder them. Far right is a small pair of cheap side cutters. I use those for anything I don't want to use my flush cutters for. Their blades are hardened better than the flush cutters so they don't damage as easily.

31

22

Soldering Tools and Materials from Beginner to Advanced (Part 2) (lemmy.ca)

submitted 1 year ago* (last edited 1 year ago) by [email protected] to c/[email protected]

0 comments fedilink

#Isopropyl Alcohol

If you're soldering you need isopropyl alcohol (or another alcohol. I have methyl, ethyl, and isopropyl in wash bottles under my desk all the time. Be forewarned that if you're using methyl the molecule is small enough to move through your skin easily and it's toxic so be cautious.) I have a wash bottle under my desk. I keep a little pill bottle full of isopropyl alcohol on my desk that I drop little boards in when I build them and shake to clean. You'll also need a little brush but I'll cover that next.

You need to clean the flux off your solder joints because your boards look nasty if you don't and the flux can corrode the traces on the board and the pins on your components.

#Brushes

I use a simple acid brush that you can buy individually or in bags of 10 at any hardware store for a couple of dollars.

images

I drill a small hole through the ferrule and put an M3 machine screw through with washers on either side to hold the bristles in place. I then cut the bristles down so that they are shorter and stiffer.

When I'm cleaning I add isopropyl alcohol, scrub with the acid brush, then rinse with clean isopropyl alcohol.

#KimWipes

This is one that I've had around for years but didn't think to use when soldering. They are a laboratory wipe and they are lint free. I use them with isopropyl alcohol to wipe anything I don't want to leave a bunch of lint on. They're relatively expensive but if you only use them for cleaning with alcohol a box will likely last you for years. You can buy KimWipes on Amazon by the box.

#Polyamide/Kapton Tape

This stuff is AWESOME! If you've taken apart old electronics of seen inside a spacecraft you've likely seen kapton tape. It's the same color as old amber beer bottles. The nice thing about it is that it's tolerant of extremely high temperatures. You can tape things down that you're soldering and it won't melt unless you heat it directly. It's good from -269°C (-452°F) up to 400°C (752°F). The stuff is magic.

#Solder Removal - Solder Wick

When you're soldering things you're eventually going to want to desolder something. The first thing most people use is solder wick. It's a braid of fine copper wires coated in flux. You place the solder wick on the solder joint, heat is up, the solder melts, and wicks into the solder wick. With practice you can get good at removing components with solder wick.

You will move on from solder wick, though, to a solder sucker at some point. Keep the solder wick. I use it after I've removed components with the solder sucker to really clean up the pads in preparation for resoldering.

#Solder Removal - Solder Sucker

The venerable solder sucker. It's a spring loaded monstrosity that does a decent job in certain circumstances. When you only have access to one side of the board you have to heat the joint, remove the soldering iron, place the solder sucker, and press the button before the solder melts hoping that you remembered to push down the plunger. They can be frustrating to use. When you have access to both sides of the board you can heat from one side and suck from the other. With practice you can suck the solder out of a join so completely that the component lead just pulls or falls out of the hole.

#Tip Cleaner/Tip Tinner

Maintenance of your soldering iron tip is essential. A clean, well tinned tip makes everything about soldering easier. In fact, in aerospace soldering you clean the solder wire and cut a short piece, clean the joint to be soldered, and clean and tin your tip before soldering each joint. I ordered a copper scrubber style tip cleaner off AliExpress. Just between us, I ordered 4 because they were cheap. I modified mine by adding a disk of thick steel to the inside of the base and a silicone rubber disk to the outside so that it doesn't move around. I quickly stick my tip in every two or three joints then get right back into the soldering. When I'm ready to put my iron away at the end of the session I jab it in three or four times moving it around to really clean off the tip then I heavily tin the tip, shake off the excess, and hang up my iron in the holder.

The tip tinner is a mixture of solder powder and aggressive flux. You turn your iron up high, melt it into the cleaner, then stir it around a bit. It really cleans up and tins your tip.

32

23

Soldering Tools and Materials from Beginner to Advanced (Part 1) (lemmy.ca)

submitted 1 year ago* (last edited 1 year ago) by [email protected] to c/[email protected]

0 comments fedilink

In this post I'm going to try to pull together some photos, some comments, and some advice from my more than 40 years of hobby soldering.

The most important advice that I can give you is to buy the best tools and materials that you can afford. You don't need to start with a $1,000 soldering station but buy the best iron you can afford. I strongly recommend buying a basic pencil iron from a well known brand for your first iron.

#Soldering Iron

You can buy a Weller for USD$30 or Hakko for USD$50. Either of those irons is a great place to start. If you can't afford one of those then get what you can afford. The iron isn't as important as other things that I'm going to talk about.

#Solder

The next thing to consider is solder. Buy good solder. Most good solders you can buy in small, affordable quantities. I buy solder in 125g (1/4 lb), 250g (1/2 lb), and 500g (1 lb) rolls and they last a LONG time. If you're not doing a lot of solder you can buy a tube and it will do you for a good, long while. Again, I recommend buying a good brand name solder. I use MG and Kester and Multicore. They are all great solders. You want to get a rosin or flux core solder.

Here's a picture of the solders that I have on my desk right now.

They are (from upper left clockwise):

FSH 6045 CKF

This one is actually a silver brazing solder. It's 45% silver and used when you really, REALLY want things to stay stuck together.

MG 4900-112G 0.032" (0.81mm) Sn96.2/Ag2.8/Cu0.4

This is a strong, lead free silver containing solder that I use for important repairs where I want a strong, lead free joint.

Kester 24-6040-0053 0.050" (1.27mm) Sn60/Pb40

This is a medium weight tin/lead solder. I use this one for heavier through hole components and heavier wires.

Multicore 370 Flux 0.064" (1.63mm) Sn63/Pb37

This is the heaviest solder that I keep on my desk. This is another tin/lead solder and I use it for heavy filling and heavy wires. If I'm going to solder a power cable or a wire on my trailer this is the one I use.

Kester 24-6337-0001 0.10" (0.25mm) Sn63/Pb37

This is the other end of the solder spectrum. This tin/lead solder is the lightest solder that own. It's extremely fine and I use it for soldering the smallest of surface mount components. I use this when I'm using a needle tip on my PES51 pencil iron to solder an 0402 surface mount resistor.

Kester EP256 Sn63/Pb37

This one is a tin/lead paste solder. I've used it a couple of times but all of the soldering that I do on a regular basis is done with an iron and wire solder so this is more of a novelty on my desk in case I ever need it.

MG 4884-227G 0.025" (0.64mm) Sn63/Pb37

This one is my go-to solder for just about everything. It's a tin/lead solder that's small enough for small surface mount components but big enough for larger through hole components as well. When I reach for solder 99.5% of the time it's this one that I'm reaching for.

#Flux

Buy liquid flux.

Seriously. It's life changing. I bought liquid flux for the first time a few years ago after soldering for more than three decades and I can't believe that I struggled for as long as I did without it. You know how when you reheat a joint the solder gets all rough and you get peaks and points that you can never get to go away? A drop of liquid flux on the joint and it's beautiful, smooth, and shiny.

Did I mention that you should buy liquid flux?

I use Kester 186 liquid flux. You can buy it in little squeeze bottles on Ebay. Flood your work with liquid flux. I literally cover what I'm working on in liquid flux. It's a bigger-hammer solution but it makes life so much easier.

Seriously, go to Ebay right now and buy some liquid flux.

33

11

Intro Post - MapleEngineer (lemmy.ca)

submitted 1 year ago by [email protected] to c/[email protected]

10 comments fedilink

Hello.

I'm MapleEngineer. I'm from Eastern Ontario and I've been soldering for over 40 years as a hobbyist. My user name is MapleEngineer because I'm an artisan maple syrup maker and design and build my own machinery and industrial controllers.

I, like just about everyone, started out with a pencil iron and a bit of solder in a clear plastic tube.

If you're into electronics and soldering please subscribe and feel free to contribute and ask questions.