| Nuts & Volts Magazine
The Solder-It Soldering Kit
BY LEW McCOY*, W1ICP*Technical Editor, CQ, 200 Idaho St., Silver City, NM 88061
There are times when a product comes along that I feel will be of special interest to our readers. The
Solder-It kit is just such an item. Over the years I have written several articles on soldering. I have seen numerous methods marketed that claimed to solder dissimilar metals, and none of these methods were really successful from my observations.
At Dayton last year, however, Fred Doob, AA8FQ, displayed a soldering kit that was truly amazing. In fact, amateurs were lined up to see and buy his product.
I approached Fred with the possibility of doing a product review for CQ, and he gave me a complete demonstration. I really felt this was something in which a lot of operators would be interested. Fred has been a representative selling products for the automobile industry. One automotive company had a very experienced metallurgist who came up with a soldering paste and material that had better bonding charateristics than normal solder and worked at lower temperatures. Fred saw the possibilities of this paste and solder for radio amateurs, so he put together a kit containing the necessary materials. Also, he designed a very small butane torch that can be used with a soldering tip or simply as a torch. The torch is refillable from one of the commonly available small butane bottles for cigarette lighters.
What will the Solder-lt kit do? Simply put a slight coating of the solder paste on the materials to be soldered. Then apply the torch flame so that the paste melts. Next apply the flame tip so the solder flows along the desired area.
There are four different tubes of paste provided: silver paste, copper paste, aluminum paste, and last, pot metal paste (that's right, pot metal paste).
Some technical points need to be included here. The aluminum solder paste will solder aluminum to other metals such as copper. It has a low melting point (395 degrees), and the resulting connection has a tensile strength of 28,000 PSI ! In fact, small soldering jobs can be done with a match or lighter because of the low-temperature paste points. One problem with many antennas is that the manufacturers use self-tapping screws to hold elements together. These screws tend to become loose, creating noise problems Not so with the Solder-It kit. Simply solder the screw in place. It's easy and quick and will hold as long as the element lasts.
One of my hobbies is making turquoise jewelry, and silver soldering is always a touchy proposition. Not so with the Solder-lt klt. You can solder at a point to hold a piece in place, then form the metal, and move along, soldering as you go. Coax fittings become very easy and simple to solder.
Frankly, as you can tell, I was extremely impressed with the kit. I don't expect it would eliminate normal circuit-board work, but for tough soldering chores it's the answer.
The Solder-lt kit comes complete with the pastes mentioned above, plus the torch and a soldering tip. Price of the kit is $59.00.
For more information write to Solder-It Co., Fred Doob, AA8FQ P.O. Box 20100, Cleveland, OH 44120 (telephone 216 791-4600).
CQ JANUARY 1993
Solder-It Soldering Kit
Reviewed by Mike Grulber, WAISVF
No doubt about it -- soldering is essential to almost any electronics project. As many hams and hobbyists have discovered, it is also a great way to make many home
repairs. Unfortunately, solder is not with out its limitations and drawbacks. Electronics-type solder, usually a mixture of 60% tin and 40% lead with a rosin-core flux, works on a limited number of metals. And, as Murphy's Law would have it, the most critical soldering jobs are always just out of reach of an extension cord. The Solder-lt kit is intended to overcome both of these limitations. The kit includes a refillable butane pencil torch, torch stand, syringes with solder pastes for a variety of materials, and a vinyl plastic storage pouch.
I find the quality and performance of the torch to be consistent with its price tag. It seems well made and durable. It' s an excellent choice for general purpose and home hobbyist soldering. The torch isn't a replacement for your soldering iron, but it is an excellent choice for soldering wires outdoors. Butane for the torch must be purchased separately. It's widely available as fuel for refillable cigarette lighters. I purchased a 2.5- ounce container (large enough for several torch refills) for $2.39. Filling the torch is a snap-just press the butane container nozzle into the torch valve. According to the manufacturer, a refill lasts an hour or more. Although I didn't time it, a fill-up did last a surprisingly long time. Fuel did not appear to leak, even when the valve was closed and the torch left idle for several weeks.
ARRL staffer and resident antenna expert. Dean Straw, N6BV, reports excellent results with a Solder-It pencil torch while at the top of his 120-foot tower. He cautions, however, that even moderate winds have an adverse effect on the torch's flame and heating ability. Solder-It is introducing some optional wind-proof tips, but these were not available for the review. Dean also admits to more than one accidental drop test and recommends a tether line from the torch body to the tower.
The plastic torch stand, which looks a bit like a top hat with the top cut out, holds the torch upright on a flat surface. The kit includes two types of tip attachments: a blow torch and a soldering iron tip. Thirteen optional tips, including a hot knife and a variety of chisel and wind-proof tips, can be purchased separately. Solder-lt also offers a lighter-duty optional torch that's a little easier to carry around. You can specify either torch with the kit, or buy them separately.
The Solder Paste Syringes
I find the specialty solder-paste syringes handy to use. Flux and solder are contained within the paste, so there are no messy flux brushes to clean or replace. You just apply the paste to the solder joint and heat. It's that simple.
As with any product of this type, the importance of eye protection and proper ventilation cannot be overemphasized. All of the solder pastes contained within this kit tend to smoke and splatter. Always be extra cautious whenever using a torch or any unfamiliar type of solder.
All of the solders in this kit are specified to have a low, or very low, melting point. The silver-bearing solder, in fact, is even touted to work with the heat of a match or lighter. Keep in mind, however, that these low-temperature claims are relative to solders in general, not to the familiar 60/40 rosin-core solder used in electronics. The melting point of 60/40 is actually a bit lower than these Solder-It products.
Aluminum solder. Aluminum solder has many uses around the household or shack. Refrigeration systems, radiators, storm doors and windows are all potential candidates for aluminum solder, but antennas are no doubt of most interest to amateurs. Who hasn't broken an element or two on his favorite Yagi at one time or other-I know I have! One antenna repair could save enough to pay for the entire Solder-It kit.
I've tried aluminum solders before, with disappointing results. Aluminum has always been difficult to solder, but the Solder-It product boasts not only of soldering aluminum to aluminum, but of soldering aluminum to other metals as well. The specified melting temperature is 395F. The tensile strength is 28,000 PSI with a finished joint that is stronger than the base metal. The color match is ideal on aluminum.
I used several aluminum and other metal samples to test the aluminum solder paste. I achieved acceptable results in almost all cases, including aluminum to aluminum and aluminum to brass. Some types of aluminum-roof flashing for example-cannot be soldered with this product, but it works fine with 3003, 6061, 6063 and other alloys I've used for antennas and equipment enclosures.
It takes a little practice to develop the technique. Be sure to thoroughly clean the surfaces to be soldered (I used steel wool) and apply heat only around the solder paste until it begins to bubble. Now apply heat directly to the joint until it flows, then immediately remove the heat. I recommend a practice joint before attempting anything critical.
Pot Metal Solder. One of my other hobbies is the restoration of a 1952 MG TD. During a carburetor overhaul session a few years back, I was a little less careful than I should have been with the one of the float-chamber covers. As you have probably guessed, much to my chagrin, that precious little lid was made of pot metal! At that time, I had no way to repair it, and finding another exactly like the original was both difficult and expensive. Ouch!
Pot metal, and similar die cast metals contain zinc. Its popularity stems in part from the ease with which it can be cast. Relatively low casting temperatures, minimal die wear and good surface finish make pot metal parts cheap and easy to produce. You'll fnd pot metal in carburetors and other car parts, trophies, junk jewelry and toys. I have even encountered pot metal on my antique crank-up Victrola machine! The down side to pot metal, of course, is a lack of durability. It's not particularly tough stuff.
Enter Solder-It pot-metal soldering paste: I tested it by joining the wings of two die cast toy airplanes. I cleaned both mating surfaces with sandpaper and applied the paste. The metallic shine of the metal solder soon began to emerge from the paste and form a molten ball. Shortly thereafter, the solder began to flow and I removed the heat.
When the joint cooled, I tested its integrity by bending the wings, both of which broke before the joint. I was extremely impressed with the results, and can recommend this product for making pot metal repairs. Again, make several practice joints before attempting anything critical. The flow characteristics are considerably different than with other solders. The syringe label indicates that the solder has a melting temperature of 400F with a tensile strength of 22,000 PSI.
Silver-Bearing Solder. The silver-bearing solder performed well in all cases that I tried, including copper and brass joints. It is also specified to work on other metals, too, including bronze, nickel, platinum, chrome, monel, stainless steel, galvanized metal, gold, silver, coated steel, cast iron, black steel and steel. The sales literature says that this solder is very conductive with a 2% silver content, and a joint that is 5 to
10 times as strong as conventional solder. Neither tensile strength nor conductivity are specified, however. The syringe label indicates that this solder has a melting temperature of 430°F.
The sales literature also touts this solder as being particularly useful for soldering PL-259 connectors. I tried using the paste to solder PL-259s, but found that conventional wire-type rosin-core solder is easier to use because it allows more control over the amount of solder added to the joint.
The literature indicated that conventional 60/40 solder has a melting point of 610°F, which is inconsistent with other references that peg it at 361°F-somewhat lower than the Solder-It silver paste. A telephone call to Richard Bell, who developed the Solder-lt syringe concept, revealed that the literature was in error. Richard explained, however, that although they have a higher melting temperature, the tiny solder particles in the Solder-It silver paste melt sooner than wire solder because of their small size. My personal feeling is that even if the smaller solder particles melt sooner, a good joint still requires the PL-259 connector body, or any work piece, to be hotter than the solder's melting point. A higher melting temperature therefore still translates into higher connector body temperatures during the soldering process.
I decided to ask several HQ staffers with varying levels of soldering experience to try soldering PL-259s with Solder-It paste and conventional solder. They all found it
easier to work with conventional solder. (Of course years of conventional soldering experience is no match for the few minutes spent with the Solder-It product. With practice, you may prefer paste to wire solder for soldering PL-259s.)
Plumber's Solder. The old favorite of plumbers, 50% tin and 50% lead, has been banned for several years because of concern over the health hazards of lead contamination in our water. The most common replacement plumber's solder is 95% tin and 5% antimony. Although 95/5 is considered far less hazardous than 50/50, there
are still heath concerns about the antimony. The Solder-It product boasts no lead, cadmium or antimony. The tube's label, however specifies that it contains copper.
This solder has a melting temperature of 430F and can be used on copper, brass, stainless steel, nickel and bronze. The label also states that the finished joint is a bright silver that will not tarnish or blacken. Its tensile strength is not specified, but the label indicates that it is five times as strong as ordinary solder.
I used a sample piece of 1/2-inch type L copper tubing and a 90 degree elbow for my test solderjoint. I cleaned both mating surfaces to a bright metallic shine with steel wool before applying the solder paste. Using the pencil torch, I heated the assembled joint. The result was a perfect solder job the first time, but the following should be noted:
- The pencil torch works fine, but it's not a replacement for an acetylene or propane torch if you have a lot of plumbing to do. Although I used the hottest portion of the flame, the tip of the inner blue cone, it took a while to sufficiently heat the joint.
- Once the joint is assembled, it is more difficult to add solder and control the amount of solder in the finished joint with the paste than with wire solder. The paste
sometimes runs off if the work is already hot, and the plastic syringe tip can melt if it touches the metal. The amount of solder in my initial test joint was minimal but adequate.
As a radio amateur, hobbyist and homeowner, this kit impressed me. It offers the ability to solder an unbelievably wide range of metals. As an antenna experimenter, I also like soldering capabilities in the field, and on the rooftop and tower without the
need for a long extension cord or recharging batteries.
You can expect a learning curve with each of the solders in the kit. The torch seems to be of good construction, and the pastes eliminated the need for a flux can and brush. Each of the solders performed as well, or better, than I expected. In terms of dollars and cents, I can think of several repairs to antennas and car parts that would have more than paid for a Solder-It Kit. It can be extremely handy to have in anyone's toolbox or workshop.
Manufacturer: Solder-It, Box 20100, Cleveland, OH 44120; tel 216-791-4600. Manufacturer's suggested retail price: Solder-It soldering kit, $59. Additional torch (standard or light duty), $39; replacement solder-paste syringes, $6; optional tip attachments, $5 to $14.
THE BOTTOM LINE:
The Solder-It Kit offers the ability to solder an unbelievable wide range of metals. For the antenna experimenter, it makes a compact package good for extended use in the field and on the rooftop.
by Marc Stern
Take this month's product, Solder-lt.
It's a simple idea that for the last couple of weeks has had me saying, "Where have you been all of my
hobbyist life?" I mean it, the idea is so subtly simple that you never realize just how much of a breakthrough it is for the hobbyist until you have used the product for a while. Imagine being able not only to solder things at lower-than-normal temperatures, but also soldering metals you never thought you would be able to solder, such as aluminum to aluminum, aluminum to copper and the like. You can do it with Solder-It. Solder-It, available from Solder-lt Co., Box 20100, Cleveland, OH, 44120, (216) 791-4600, is a series of specialty soldering pastes. There's a silver-bearing paste for normal electronics soldering; an "aluminum" paste that enables you to solder aluminum to aluminum or copper to aluminum; a "copper" paste that lets you work on copper piping or plumbing, and a "pot metal" paste that lets you solder to pot metal or
pewter or other like types of metal.
The pastes are distributed separately or as part of a $59 kit that includes a nifty butane torch. You can purchase the pastes for $6 and the torch for $39.95. I think the kit is the better buy and since you'll use it a long time, the cost is very reasonable. You can also purchase different torch tips that include a blower-deflector combination that's great for heat shrink tubing.
The pastes allow you to join things at temperatures that are below standard soldering temperatures. Normal
solder flows in the 600 degree Farenheit range, while Solder-It flows in the 395- to 430-degree Farenheit range. This means that for many purposes a simple butane lighter will suffice to solder somethlng. As a Radio Amateur, I like the lower-than-normal soldering. For example, look at the series of photos that accompanies this article. You can see a typical coaxial cable connector being put together. If you look closely. you won't see the traditional heavy duty, high-heat soldering iron or gun. Instead, you'll see a cigarette lighter and torch handling the soldering chores. Yes, that's right, a butane cigarette lighter.
The reason this is possible is that Solder-lt is a silver-bearing soldering paste that begins to flow with lighter heat. It's warm enough to get the solder to bond, but not warm enough to melt or distort the coax's dielectric material. That's quite a breakthrough, at least in my humble opinion.
Imagine being able to solder coaxial cable connectors and not having to worry about melting the inner dielectric material. Look at photos A-D and you will see the steps I needed to make a solid connector.
In Photo A, you inject -- it looks like a syringe for good reason -- the solder paste into the tip of the connector.
In Photo B, you heat the tip of the connector with a standard butane cigarette lighter (any-one will do) . The
paste quickly flows and the center conductor and connector's center pin are securely joined The bond is at least as strong-if not stronger-than standard 60/40 rosin core solder.
In Photo C, you inject the solder paste into the connector, getting ready to bond the braid to the connector shell.
In Photo D, you bond the connector shell to the shield braid of the coax. The only difference here is that you need a higher heat pencil torch to do the chore. A quick blast with the torch and the connector is complete. It doesn't take long to accomplish.
Whenever I make up a new coaxial connector, using Solder-lt takes a load off my mind. When I have made up
cables in the past, I have used the traditional monster, high-heat soldering gun and standard solder. The problem was that this setup almost guarantees that once in a while you will leave things cooking a bit too long and the inner dialectric will melt. Every time I have made up a cable this way this thought has been in the back of my mind, but, now with Solder-lt that has all changed.
Additionally, Solder-It has let me enjoy my hobby in new ways. I have been an Amateur Radio operator for years
and one of my passions has been fiddling with antennas. Like most hams who are interested in antennas, I have
probably done more antenna-making than I have operating. And, if you know anything about antennas, you always need
a soldering iron handy to complete a job.
There are times, though, when you can't solder the work and must have a torch available to do some braising to
get things together. Solder-It, I have found, puts a new perspective on things. I wish I had had it when I was working with some aluminum that I had to join together to complete a test ground plane.
Now, you know as well as I do that soldering aluminum to aluminum is next to impossible, if not totally so. So,
you can imagine how frustrated I was when things wouldn't go together.
All of this was a few years back and the washout was that I put the project on the shelf and forgot about it. After using Solder-lt in a recent test, all I can say is where has this product been all my hobbyist life? A simple test has changed the way I do things: Joining two pieces of aluminum by spreading an even layer of Solder-It between the pieces and heating it with a butane torch.
Of course, there is a learning curve with Solder-lt. It did take me a few tries to get things working correctly. But, it didn't take long, especially when I remember learning to solder so I could complete my first Heathkits back in the 1970s. More than one discreet device went up in smoke as I strong-armed the iron where a delicate touch was needed. It took some time but, believe it or not, I did learn. Solder-It would have made soldering boards much easier and safer for the devices from a heating standpoint.
Having used Solder-It for a time, there are a couple of items that I found that you should remember.
First, even though there is no lead or antimony in Solder-It, it still does sputter and give off some smoke, so I would recommend using it in a well-ventilated area. Solder-It recommends it, too.
Second, if you can't use it in a well-ventilated area, be sure you have a fan or something else going to dissipate the fumes. They can get concentrated over your work area and can become annoying.
It is true that those are rather minor nits to pick, but, they do have to be mentioned.
If you are interested in finding out more information, you can contact Solder-It Company directly and they will be happy to send you some product information. NV
Marc Stern, WAlR, has been writing hobbyist, computer and consumer electronics articles since the 1970s A technical writer for a large computer corporation, Marc is also a computer systems manager and technical trainer. Marc's articles have appeared in "CQ," "Radio Electronics," "Information Systems News," "Popular Mechanics," and more. To date, Marc has written more than 200 articles.
Nuts & Volts Magazine/December 1992