Make: Electronics by Charles Platt (classic books to read TXT) 📗

hand” (or “third hand”) has two alligator clips that hold components or pieces of wire precisely in position while you join them with solder. Some versions of the “helping hand” also feature a magnifying lens, a wire spiral in which you can rest your soldering iron, and a little sponge that you use to clean the tip of your iron when it becomes dirty. These additional features are desirable. Helping hands are available from all electronics hobby sources. Examples are the catalog item HH55 from Elenco or model 64-2991 from RadioShack. See Figure 3-3.

Figure 3-3. The helping hand is fitted with two alligator clips to hold your work. The metal spiral is a safe place to holster a hot soldering iron, and you use the sponge to wipe its tip.

Essential: Magnifying lens

No matter how good your eyes are, a small, handheld, powerful magnifying lens is essential when you are checking solder joints on perforated board. The three-lens set in Figure 3-4 is designed to be held close to your eye, and is more powerful than the large lens on a “helping hand.” The folding lens in Figure 3-5 stands on your workbench for hands-free operation. Both are available from RadioShack and similar items are stocked by art supply stores and hobby shops. Plastic lenses are quite acceptable if you treat them carefully.

Figure 3-4. As long as you treat it carefully, a cheap set of plastic magnifying lenses is perfectly acceptable. Handheld magnification is essential for inspecting the solder joints that you make on perforated board.

Figure 3-5. This kind of folding magnifier can stand on your desktop and is useful for checking part numbers on tiny components.

Essential: Clip-on meter test leads

The probes that came with your multimeter require you to hold them in contact while you make a reading. This requires both hands, preventing you from doing anything else at the same time.

When you use a pair of “minigrabber” probes with little spring-loaded clips at the end, you can attach the Common (negative) lead from your meter to the negative side of your circuit and leave it there, while you touch or attach the positive probe elsewhere.

The Pomona model 6244-48-0 (shown in Figure 3-6) from Meter Superstore and some other suppliers is what you need. If you have trouble finding it or you object to the cost, you may consider making your own by buying a couple of “banana plugs” (such as RadioShack part 274-721) that will fit the sockets on your meter, and then use 16-gauge or thicker stranded wire to connect the plugs with IC test clips, such as Kobiconn 13IC331 or RadioShack “mini hook clips,” part number 270-372C. See Figures 3-7 and 3-8.

Figure 3-6. These “minigrabber” add-ons for meter leads make it much easier to measure voltage or current. Push the spring-loaded button, and a little copper hook slides out. Attach it to a wire, release the button, and you have your hands free for other tasks. It’s a mystery that meters are not supplied with these grabbers as standard equipment.

Figure 3-7. To make your own minigrabber meter leads, first attach a banana plug to a wire by sliding the wire through the cap, into the plug, and out through a hole in

the side.

Figure 3-8. Then screw a collar over the protruding piece of wire, and screw on the cap. The other end of the wire is soldered to a probe.

Essential: Heat gun

After you join two wires with solder, you often need to insulate them. Electrical tape, sometimes called insulating tape, is messy and tends to come unstuck. You’ll be using heat-shrink tube, which forms a safe, permanent sheath around a bare-metal joint. To make the tube shrink, use a heat gun, which is like a very powerful hair dryer. They’re available from any hardware supply source, and I suggest you buy the cheapest one you can find. See Figure 3-9.

Figure 3-9. Like an overpowered hair dryer, the heat gun is used with heat-shrink tubing to create a snug, insulated sheath around bare wire.

Essential: Solder pump

This little gadget sucks up hot, melted solder when you are trying to remove a solder joint that you made in the wrong place. Available from All Electronics (catalog item SSR-1) or RadioShack 64-2086. See Figure 3-10.

Essential: Desoldering wick

Also known as desoldering braid. See Figure 3-11. You use this to soak up solder, in conjunction with the Solder Pump. Available from All Electronics (catalog item SWK) or RadioShack (part 64-2090).

Essential: Miniature screwdriver set

Dinky little electronic parts often have dinky little screws in them, and if you try to use the wrong size of screwdriver, you’ll tend to mash the heads of the screws. I like the Stanley precision set, part number 66-052, shown in Figure 3-12. But any set will do as long as it has both small Phillips and straight-blade screwdrivers.

Recommended: Soldering stand

Like a holster for a gun, you rest your soldering iron in this stand when the iron is hot but not on use. Examples are catalog item 50B-205 from All Electronics, RadioShack model 64-2078, or check eBay. See Figure 3-13. This item may be built into the helping hand, but you need an extra one for your second soldering iron.

Figure 3-10. To remove a solder joint, you can heat the solder until it’s liquid, then suck it up into this squeezable rubber bulb.

Figure 3-11. An additional option for removing liquid solder is to soak it up in this copper braid.

Figure 3-12. A set of small screwdrivers is essential.

Figure 3-13. A safe and simple additional stand for a hot soldering iron.

Recommended: Miniature hand saw

I assume that you will want to mount a finished electronics project in a decent-looking enclosure. Consequently, you are likely to need tools to cut, shape, and trim thin plastic. For example, you may want to cut a square hole so that you can mount a square power switch in it.

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