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SOLDERING BASICS As with most aspects of modeling, you must do things properly and with the right tools. Soldering is almost an art. I will simply touch on the bare-bones basics here. To properly solder any electrical connection, you must use solder designed for this application. Never use acid flux plumbing solder! Any good electronics-grade solder should be fine. The type with water-based flux should be washed thoroughly after soldering. Use the proper soldering iron, one that provides the right heat and has a 1/8 to 1/4-inch tip with a power range from 40 to 125 watts. The thermal mass (size) of the tip has as much to do with the heat transfer as the heating power of the element. The right iron should cause the solder to flow nicely into the joint within a few seconds (perhaps 3 to 5). It is important to have the tip clean and shiny and with a fresh coating of solder, commonly called “tinning.” Strip the wire back 5/16 inch, just enough for the wire to fully fit into the contact wire recess (also known as a solder pocket). Try not to nick the wire or leave any stray strands outside the contact. Unless you have three hands, put the wire in a small bench vise with the stripped end up and the contact in place on the wire. Put the iron tip on the contact at the end of the wire and flow just a bit of solder between the tip and the contact.
Wetting this junction with a tiny amount of liquid solder results in better thermal conduction and allows the parts to heat together. You should see the solder start to flow within a few seconds. Once that happens, add only enough additional solder so that it flows into the inside of the contact and the core of the wire. It is important not to use too much solder, as it can begin to flow down into the wire’s insulation. Running solder down too far will cause a stress point that may cause the wire to break with repeated flexing. FAA “full-scale” maintenance standards recommend crimped connections and not soldered connectors specifically for this and other reasons. Once you have completed the joint, inspect it. There should not be any solder on the outside of the housing. If there is, you may have difficulty inserting the contact into the housing. You should also avoid having any solder on the flat contact surface near the “spoon” area as in the middle example, as this will destroy the connector’s performance. If you have a blob of solder on the outside of the contact body, you may file or scrape it off. If there is solder on the contact-mating surface then re-do the connection with a new contact. CRIMPING—AN EASIER, BETTER WAYCrimping Powerpole contacts is much faster and easier, but it must be done with the correct type of crimping tool. Both Anderson and West Mountain Radio offer such tools. The West Mountain tool, the PWRcrimp, does all three sizes of contact pins.
To crimp a contact with either an Anderson or WMR crimp tool, put the contact on the wire with the contact seam up and insert it fully into the right die for that size contact. Put it fully into the tool’s contact positioner stop. Squeeze the tool just until its ratchet releases. Properly crimping with one of these tools will guarantee you an aerospace quality connection with lower resistance and higher reliability than the best solder job. Crimping forms a “compression weld” with superior conductivity. IMPORTANT BATTERY CONNECTION TIPS
Safety comes first! Before attaching connectors to batteries, or wiring potentially “hot” power buses, voltage regulators, etc., take off any metal rings or jewelry. If you accidentally shorted a battery through a ring, you could lose a finger. Note that when putting any connector on a battery, it is important to proactively prevent accidental shorts. Do one wire at a time, add protective tape on the second wire before starting, and do not put the second contact on until the other contact is safely inside its housing. You can assemble connector halves in various ways so that they are impossible to plug into the wrong mate. Use one arrangement between batteries and speed controls, another between your speed control and motor, and still another between your charger and your 12-volt field power source. As mentioned before, you might do your Li-Poly different from other battery types to avoid using the wrong charger. The housings are cleverly held together with small dovetail joints. Look at them closely and you will see how they assemble and work. The housings slide together; do not try to snap them together or apart. Mating pairs of connectors will connect together with three to five pounds of retaining force and be vibration proof.
It is important that the dovetails are fully mated and are flush; if not, the finished Powerpoles will not connect properly. To make pairs permanent, use a small drop of CA only after you are certain that they are the way you want them forever. I never permanently glue my housings together, and they normally stay in place just fine. DISASSEMBLING POWERPOLES Unlike other connectors, Powerpoles may be disassembled without cutting the wire or unsoldering. The contacts may be removed from the housings by prying the ends of the contact away from the retaining springs with a small screwdriver and pulling them out. Assembled housings may be slid apart, but they can be stubborn, or impossible to separate if you glued them. If they are stubborn, put the bottom edge of the appropriate housing on a solid object and tap the other end so that it slides down. Twisting them slightly before sliding helps, but do not try to snap them apart and thereby damage the dovetail. MODIFYING POWERPOLES If you are worried about the size or weight of Powerpoles in your park flyer, you can easily cut them down, making them as small as any other high performance connectors. Put the housings together without the contacts inside and use a hobby saw to trim off the backs. Cut them just at the back of the indent that is in the housing. You may also use a razor cutter such as a Sears Handi-cut to cut them cleanly and quickly. Once you are familiar with Powerpoles, you will find how convenient they are and how well they perform. More power to you! [Powerpoles are available from most hobby stores as Powerpole, APP or Sermos connectors. PWRcrimp Powerpole crimp tools are available from West Mountain Radio and their dealers. Price—$49.95 (PWRcrimp Tool; for 15A, 30A and 45A contacts). Anderson also makes two crimping tools, available from Powerwerx. Price—$159.95 (15A-30A contacts); $159.95 (45A contacts).] For more information, please see the source guide in the magazine. Links Anderson Products, www.andersonpower.com. Final Page |
