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Problem with soldering gun
Two good posts below, HOWEVER...
Guns, in general, should not be used for PL259s -- though W4ZCB's method is a good one. I have used this technique in the past, but don't recallspecificlly on what, just that is was a massive solderiang job. I also have a device, resistance solderer, that designed to do this and is used for doing dental soldering...and now, PL259s. This type of tool puts the full power available into the stuff being soldered. If it is enough to quickly heat the object, then it works. In its normal mode. a gun puts the power into the whole gun "wire" and this must then transfer heat to the work through conduction - usually via a very small contact point which is an inefficent thermal conveyor. The remaining gun "wire" is accepting the vase bulk of the power and, therefore it is wasted (un-used to heat the work). Soldering things like PL259 generally requires thermal capacity, not just temperature. "Guns" are not well suited for this work. This is accomplished with a LARGE tip. You need to get in, heat quickly and get out quickly. The large tip allows you to heat, in a shirt time, the _work_, which also has a large thermal mass, without cooling the tip appreciably. To do a good job, you should be able to heat the shell in less than something like 2 seconds, apply solder, let it flow and get out in a total of something line 5-6 seconds. I think the gun tip-wires turn red-hot, back from the tip, because you are using the PL259 to keep the real "tip" cool and continuing to run the high current through the tip WAY too long. The power needed to maintain the tip's temperature is not enough alone. It is not really the wattage of the heater, but the thermal capacity of the large tip that gives the amount of and rate of heat transfer needed. 73, Steve, K.9,D;C'I A trick demonstrated to me by a friend in New Mexico. (I use "N"'s and it doesn't bother me, but he was putting a 259 on a piece of coax and managed to amaze me.) You use a soldering gun, but with NO tip at all! He pushed the gun sans tip into the ring where the holes for the solder to the braid are, and pulled the trigger. In very little time, the I*I*R losses had the 259 hot enough to melt solder and he flowed it into the braid. Gets the heat into the right place, Give it a try. W4ZCB wrote in message ups.com... Guys, electronics technology and densities have changed quite a bit over the past 40 or so years. My first two soldering tools back in the 1950s were a 100-Watt American Beauty soldering iron, and a Weller Soldering Gun. By around 1965, both were too large and bulky to do precision work on the by then modern electronic, so I purchased a 37-Watt pencil iron (an Ungar Woodburner we called it at that time) which served my needs up to roughly 1989, when I added a miniature, variable temperature soldering iron to my collection which remains in use today. That original Weller Soldering Gun fell into disuse at least 25 years ago, except for emergency use in panic situation to light cigarettes, although I do take note of the fact that it was very useful for making quick-fix field repairs on the older, low-density, vacuum tube electronics, tinning the ends of power cords, etc. I continue to use the 100-Watt American Beauty through this day, but only for relatively heavy job like soldering the braid on RG-8U cables to the connectors. Works fine on that application, particularly since its temperature tends to remain rather constant so it doesn't either oxidize most solders or destroy the item that the cable is being attached to. Arguably, most of the soldering I do today is performed by my temperature controlled iron, generally at temperature settings of 625 or 720 degrees depending on the particular solder that I am using. Once or twice a year do I resort resort to the American Beauty. (It was a gift from my dad back in 1955 and remains in occasional use through this day.) Even years back, I simply can't remember any soldering iron tip that was pure copper (except for some of those antique iron that you heated on your gas stove). Soldering iron tips are usually plated with an iron coating, and for very good reason. The iron coating slow the pitting and eventual disolution of the tip in molten solder, which in turn extends the life of the tip. Kindest regards, Harry C. p.s., I now recall that the earliest Weller Soldering Gun tips were bare copper, which required you to replace them at the rate of about 1 tip per week in regular daily use. Those sold today are iron coated. Still, today I know of no one using Weller Soldering Guns for electronics, however, for the arts and crafts they can be very useful. |
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