Soldering Tutorial

soldering iron how to solder

Soldering Tools:

Soldering Iron – a hand tool that heats up in order to melt solder around electrical connections

Soldering Station – used to precisely adjust the temperature of the soldering iron

how to solder sponges

Sponge – helps to keep the soldering iron tip clean by removing the oxidation that forms

soldering iron stand how to solder

Soldering Iron Stand – helps prevent the hot iron tip from coming in contact with flammable materials or causing accidental injury to your hand

Solder – a metal alloy material that is melted to create a permanent bond between electrical parts. It comes in both lead and lead-free variations with diameters of .032″ and .062″ being the most common.

Helping Hand – a device that has 2 or more alligator clips and sometimes a magnifying glass/light attached. This clips will assist you by holding the items you are trying to solder while you use the soldering iron and solder.

Soldering Safety:

Soldering irons can reach temperatures of 800′ F so it’s very important to know where your iron is at all times. We always recommend you use a soldering iron stand to help prevent accidental burns or damage.

fume extractor solder smoke absorber

It’s always a good idea to wear protective eye wear in case of accidental splashes of hot solder. Lastly, make sure to wash your hands when done soldering especially if using lead solder.

How To Solder:

how to solder

To a circuit board:

  1. Mount the component – begin by inserting the leads of the component into the holes of the circuit board. Flip the board over and bend the leads outward at a 45′ angle. This will help the component make a better connection with the copper pad and prevent it from falling out while soldering.
how to solder
  1. Heat the joint – turn your soldering iron on and touch the tip of the iron to the copper pad and the component lead at the same time. Hold for 3-4 seconds.
how to solder
  1. Apply solder to joint – continue holding the soldering iron on the copper pad and the lead and touch your solder to the joint. IMPORTANT – Don’t touch the solder directly to the tip of the iron. You want the joint to be hot enough to melt the solder when it’s touched. If the joint is too cold, it will form a bad connection.
  1. Snip the leads – remove the soldering iron and let the solder cool down naturally. Don’t blow on the solder as this will cause a bad joint. Once cool, you can snip the extra wire from leads. A proper solder joint is smooth, shiny and looks like a volcano or cone shape. You want just enough solder to cover the entire joint but not too much so it becomes a ball or spills to a nearby lead or joint.

Wires:

how to solder wires

For this process, it’s recommended to use helping hands or other type of clamp device.

  1. Remove the insulation from the ends of both wires. If the wire is stranded, twist the strands together with your fingers.
how to solder wires
  1. Make sure your soldering iron is fully heated and touch the tip to the end of one of the wires. Hold it on the wire for 3-4 seconds.
  1. Keep the iron in place and touch the solder to the wire until it’s fully coated. Repeat this process on the other wire.
how to solder wires
  1. Hold the two tinned wires on top of each other and touch the soldering iron to both wires. This process should melt the solder and coat both wires evenly.
how to solder wires
  1. Remove the soldering iron and wait a few seconds to let the soldered connection cool and harden. Use heat shrink to cover the connection.

Desoldering

The good thing about using solder is the fact that it can be removed easily in a technique known as desoldering. This comes in handy if you need to remove a component or make a correction to your electronic circuit.

With Solder Wick (desoldering braid):

  1. Place a piece of the desoldering braid on top of the joint/solder you want removed.
how to desolder soldering
  1. Heat your soldering iron and touch the tip to the top of the braid. This will heat the solder below which will then be absorbed into the desoldering braid. You can now remove the braid to see the solder has been extracted and removed.

With a Solder Sucker:

  1. Press the plunger down at the end of the solder sucker.
  1. Heat the joint with your soldering iron and place the tip of the solder sucker over the hot solder. Press the release button to suck up the liquid solder.

Sources

Multimeter Tutorial

A multimeter is a tool that is used to measure electric voltage, current, and resistance.

Parts of a Multimeter:

Display – shows the measured value and units

Dial – used to switch between different settings

Ports – this is where the probes are plugged in

How to Measure Voltage:

  1. Plug your black and red probes into the ground (labelled “COM”) and voltage (labelled “V”) ports.
  2. Choose the appropriate voltage setting on your multimeter’s dial. Remember that most battery-powered circuits will have direct current, but the setting you select will depend on the project you are working on. For example, if your circuit is powered by a single 9V battery, it probably doesn’t make sense to select the setting for 200V, and 2V would be too low. If available, you would want to select 20V.
  1. Touch the probe tips to your circuit in parallel with the element you want to measure voltage across. Be sure to use the red probe on the side connected to the positive battery terminal, and the black probe on the side connected to the negative battery terminal (nothing will be harmed if you get this backwards, but your voltage reading will be negative).
  2. You might need to adjust the range. If your multimeter’s screen just reads “0,” then the range you have selected is probably too high. If the screen reads “OVER,” “OL,” or “1” (these are different ways of saying “overload”), then the range you have selected is too low. If this happens, adjust your range up or down as necessary.

How to Measure Resistance:

  1. Plug your red and black probes into the ground (labelled “COM”) and resistance (labelled “Ω”) ports.
  2. Choose the appropriate resistance measurement setting on your multimeter’s dial. If you have an estimate for the resistance you will be measuring (for example, if you are measuring a resistor with a known value), that will help you pick the range.
  3. Important: Turn off the power supply to your circuit before measuring resistance. If you do not do this, your reading might be incorrect. If your circuit has multiple components, you might need to remove the component you want to measure in order to accurately determine its resistance.
  4. Connect one of your multimeter’s probes to each side of the object whose resistance you want to measure. Resistance is always positive and the same in both directions, so it does not matter if you switch the black and red probes in this case (unless you are dealing with a diode, which acts like a one-way valve for electricity, so it has a high resistance in one direction and a low resistance in the other direction).
  5. If your multimeter is not auto-ranging, you might need to adjust the range. If your multimeter’s screen just reads “0,” then the range you have selected is probably too high. If the screen reads “OVER,” “OL,” or “1” (these are different ways of saying “overload”), then the range you have selected is too low. If this happens, adjust your range up or down as necessary.

How to Measure Current:

  1. Plug your red and black probes into the ground (labelled “COM”) and voltage (labelled “A”) ports. Note: It is always safer to start out with the port that can measure a larger current. WARNING Failure to do so may blow the fuse. Plug the red probe into the high-current port.
  2. Start from the highest current setting (largest number). You will probably see a 0. If this is the case, keep turning the dial to get to your target range. (If you start from low to high, you may blow a fuse). Remember to check if your circuit is direct current or alternating current, and that almost all battery-powered circuits will be direct current.
  3. Connect the multimeter probes in series to the current you want to measure. Be sure to use the red probe toward the battery’s positive side, otherwise your current reading will be negative.
  4. You might need to adjust the range. If your multimeter’s screen just reads “0,” then the range you have selected is probably too high. If the screen reads “OVER,” “OL,” or “1” (these are different ways of saying “overload”), then the range you have selected is too low. If this happens, adjust your range up or down as necessary.

Continuity Check (which ensures that there is a conductive path between two points in your circuit):

  1. Set your multimeter to the continuity check symbol.
  1. Plug your red and black probes into the ground (labelled “COM”) and voltage/current/resistance (labelled “V,” “A” or “Ω”) ports.
  2. Important: Turn off the power supply to your circuit before doing a continuity check.
  3. Touch two parts of your circuit with the probes. If the two parts of the circuit are electrically connected with very little resistance between them, your multimeter should beep. If they are not connected, it will not make a noise and might display something on the screen such as “OL,” “OVER,” or “1,” which all stand for “overload.”

Troubleshooting:

Don’t panic! There are several common mistakes that can be easily fixed.

  • Make sure your multimeter has fresh batteries.
  • Some multimeters have an auto power-saving feature, and will turn off after a certain period of inactivity. If this happens, turn your multimeter’s dial to “off” and then turn it on again.
  • Make sure you have your probes plugged into the correct ports for what you want to measure.
  • Make sure you are connecting your probes to your circuit in the correct manner (series or parallel) for what you want to measure
  • Make sure you have the correct setting chosen on your multimeter dial for what you want to measure; for example, if you need to measure DC voltage, make sure you don’t have current, resistance, or AC voltage selected on the dial.
  • If your multimeter is not auto-ranging, you might need to manually adjust your range. If your multimeter screen always reads “0,” this might mean the range you have selected is too high. If it reads “OL,” “OVER,” or “1,” the range you have selected could be too low.

Sources: https://www.sciencebuddies.org/science-fair-projects/references/how-to-use-a-multimeter#usingamultimeter

https://learn.sparkfun.com/tutorials/how-to-use-a-multimeter/all

Benchtop Power Supply Enclosure

Project by Gavin Granath – ggranat1@jhu.edu

Gavin was able to purchase an inexpensive DC power supply from ebay and then design and print his print his enclosure in the Makerspace. With accurate voltage and amperage control, benchtop power supplies make it easy to test and prototype electrical components.

Supplies and Cost:

Around $40 total cost

Adjustable 5A Step-Down Buck LCD Digital Power Supply Module 6V-32V to 0-32V USA https://ebay.us/n1pBDI

AC to DC Power Adapter with an output of DC 12V and 5A max

Panel Mount Banana Plug Female Socket

Banana Plug to Alligator Test Lead

Enclosure Machine Screws M2.5 x 10

Solidworks to Laser Cutter Tutorial

Open your part in solidworks, and make a drawing from the part. Select the custom template, and choose an arbitrary sheet size or the size of the cutting table that you’ll be working on.

Drag the appropriate view of your part onto the sheet. The outline of the drawing that you make in Solidworks will be cut out of the acrylic, so it’s important to make sure that you select the correct view. Next, make sure that the drawing is on a scale of 1:1. To check and change the scale, right click on the drawing view in the left hand feature tree and select edit feature.

Inside of the edit feature toolbar on the left hand side of the screen, there will be a box to adjust the scale. Choose the custom feature and set it to 1:1. Make sure to delete any unwanted lines in the drawing, such as axis lines or construction lines. Any lines left in the drawing will cut when printed.

To indicate to the laser cutter software whether you will be cutting out a shape, rastering it, or etching it you will need to adjust the line size and color. For the sake of efficiency, you can use a filter select tool to select all of the lines in a given drawing. Right click the top of the window (right next to the little settings option). From the drop down menu, choose the selection filter. This will bring a toolbar of selection options to the bottom of your screen.

From the tool bar options, choose the small purple filter with the line next to it. This will allow you to simply click and drag to make a box over your drawing, and select all of the lines completely contained within the box.

Before selecting your drawing, you will want to change the settings for the smallest line option to 0.002 inches. To do this, go to the options toolbar at the top of the window, which opens a larger window of different customizable features of solid works. In the second tab, labeled Document Properties, there is an option to adjust the line thickness. Change the smalles line thickness to 0.002 inches and hit okay.

Now you can go in and select all of the lines in your drawing. Once selected, simply right click in the sheet and you can bring up a small toolbar. You can adjust the color and line thickness from this simple toolbar.

To make a cut line, the color should be pure red and the line thickness should be 0.002 inches. On the RBG scale, this is equivalent to the values (255,0,0).

To make a engrave line, the color should be pure blue and the line thickness should be 0.002 inches. On the RBG scale, this is equivalent to the values (0,255,0).

To make a raster, make sure the whole area that you want to raster is filled with pure black. On the RBG scale, this is equivalent to the values (0,0,0).

Once you have finished adjusting the line properties of your drawing, make sure that you save it. It is important to note that each of the computers at the laser cutting station hooks up to a different laser cutter. The computers are labeled according to which laser cutter they are attached to, so choose accordingly based on the size of the part that you want to design and print!

Next, export the drawing to the laser cutter software (called UCP) using the print button. Make sure to print to VLS6.60.

Hit okay, and open up the UCP software from the desktop. You’ll see your part on the first page of the software, and you can read the UCP tutorial on how to operate the laser cutter software.

Laser Cutter Setup

Before using the laser cutters, it is important to turn on the compressed air as well as the fume extraction. When you cut materials they often emit fumes since the laser is burning through the material, and the air vents are an important component of the system that keeps the fumes from spreading in the space.

To turn on the compressed air, simply turn the yellow lever into the vertical position. To turn on the air vent, flip the light switch to the right of the copper tubing (it will take about 1 minute to turn on). You should hear the compressed air come on loud and clear.

** Insert photo of compressed air things

Turn on the laser cutter that you are using by holding the power button on the right side of the machine. Once on, check the list of allowable materials to make sure that you can cut the material you’ve chosen.

You can open the laser cutter using the handle on the front of the machine, and load your material inside. Before closing the machine, hit the large green run button from the UCP software. You will see the laser head move as if it were cutting the material, however there will be a low-energy red laser instead of the cutting laser. This is a great way to make sure that your cut will stay on the material that you’re cutting.

Once you have checked that your pattern will fit on the piece of material that you’re using, you can go ahead and close the lid of the laser cutter and hit the green run button on the UCP software again. This time, you should see the laser cutting for real. If you notice any flames, please stop your print and review which materials are acceptable for laser cutting. If you notice any odd sounds, or out of the ordinary cutting patterns (such as the laser head running into the material) please stop the cut, put an out of order sign on the machine and text or email Richard Mejia about the issue. The sooner you let us know, the sooner we can fix our equipment so that everyone can use it!

When you are done laser cutting, please remove your scrap material and take it with you or donate it to the scrap pile in the space. Make sure that the laser cutter, air compressor, and air vent is turned off after you are finished. ** If you are NOT the only one using the machines, please leave the air compressor and air vent on for other users!