Scaleworld

IT'S A STICKY SITUATION

If someone who knew absolutely nothing about modelbuilding asked you what was the single most important tool needed for the construction of a kit…besides the kit, of course, what would you say? A knife? Sprue cutters? Clamps? Well, they're all important, but you'd be wrong on every count. The most important tool is the one thing that we really don't think of as a tool. And what is it? Glue or cement. But even that's not the whole answer because we don't use just one kind of adhesive today, especially with multimedia kits being fairly commonplace. Fifty years ago, however, it was a somewhat different story.

When I started building models back around 1949, most were made of wood. Anyone out there remember the old stick-and-tissue flying models? They were powered by a long rubber band that ran the length of the model inside the fuselage. You wound it up by rotating the prop, then launched the model into flight by throwing it into the air and removing your finger from the prop at the same time. Believe it or not, the little puppy actually flew…and quite well, too.

At any rate, to join wood parts, we modelers had cement. Two of the best known were made by Ambroid and Testors and both are still around today. When styrene plastic took over the model world, new cements reared their sticky little heads. Testors, as you would expect, came out with their own version (along with those little ten cent bottles of paint) and another company that was quickly making a name for itself with plastic kits released what is arguably the best known and most beloved styrene cement ever produced…Revell Type 'S'.

For, I suppose, the next ten years or so (meaning sometime in the early 1960s), model cements stayed basically the same. Various companies came out with their own versions, but cement was cement was cement for all practical purposes. It was also the weak point in model construction. That's because cement was actually that - cement. Though it would grab the plastic and hold the parts together, the two parts that were joined were still two separate parts held together by that layer of cement. Break down an old model after the cement had dried for a few months -or years- and you could literally peel a layer of dried cement off the plastic, leaving the smooth plastic edge behind.

This doesn't mean that plastic (meaning tube) cement didn't work. It did. I still have models built forty years ago that are as solid today as they were the day I built them. But things were about to change. Sophistication would arrive in the form of liquid welders.

Liquid welders have an interesting property in that they literally dissolve the top layer of plastic, allowing the surfaces of two parts (you have to hold the two parts together for this to work) to intermingle on a molecular level, essentially creating a weld, allowing the two parts to become one. Done correctly, if you try to break the two former pieces apart, one of the pieces will break somewhere other than the seam you joined.

Someone discovered this stuff in the retail outlets of commercial plastics manufacturers of cast acrylic plastic products (also known by the brand name PlexiGlas). They used a little item called Weld-On #3 to join cut pieces of acrylic and …lo and behold…it did just as good a job on styrene. Somebody told somebody who told somebody and the floodgates were opened. The stuff was water thin and evaporated at a prodigous rate if you left the cap off and you were working in a hot environment. Wasn't all that good for your lungs, but somehow we learned safe ways to use it without killing ourselves in the process. A few of us even went so far as to visit our local scientific supply house to buy MEK (methyl ethyl ketone) and MEK-P (methyl ethyl ketone peroxide). Worked just as well, cost less and was also more dangerous. If nothing else, it proves that modelbuilders will try just about anything once if they think it'll work.

Anyway, as liquid welders caught on, more and more manufacturers began offering them, including Weld-On, Ambroid (they called theirs ProWeld), Testors, Tenax and many more. Which one you settled on was basically a matter of personal preference because they all did essentially the same job. My personal favorite is Ambroid ProWeld. Many of you swear by Tenax 7R while I swear at it. I flat can't make the stuff do what I want it to because it evaporates too fast, but it works wonders for many. Like they say, different strokes for different folks.

Finally, let's not overlook the exotics. By this, I mean the cyanoacrylates and epoxies. Exotic or not, a lot of modelers are now starting to use CAs (cyanoacrylates or superglues) as their only cement for both building the basic kit, creating fillets and contours, as well as filling gaps and imperfections. Now when you're building resin kits or multimedia kits where you're adding resin and photoetch components to a base styrene kit, CAs are pretty much your only choice (except for epoxies, which we'll get to in a minute).

CAs were originally available only in a water thin consistency that ran literally everywhere. Today, you have water thin, gap filling, slow cure, slower cure, gel form, even a couple of new flexible versions (one is rubber toughened and the other is designed as a flexible hinge glue) from Bob Smith Industries. Other manufacturers you may be familiar with are Pacer Technologies and Zap Adhesives to mention only a few. You also have spray-on accelerators to make the stuff kick even faster. Again, which one you use is a matter of personal preference, though I think Bob Smith Industries produces the best line of CAs you can get your hands on.

Incidentally, both Pacer and BSI (Bob Smith Industries) offer accelerators. Both speed up the cure time of CAs, but there's one very interesting difference between the two…and this comes from my personal experience. The Pacer version leaves a very slight residue on the surface after it's dried while BSI leaves absolutely zero residue. Does this make any real difference in the construction of a model? Not really, except for one thing. The BSI version can be used to get a canopy crystal clear. Wear glasses or an Opti-Visor… or have a scanner for your computer? I haven't found anything better for cleaning the glass. Sounds weird, I know, but it works.

They cure in seconds, fill gaps that can't be filled any other way, become rock hard in a short period of time and sand beautifully. I use'em all the time but, in my humble opinion, they're not a universal product that can replace every other type of cement, adhesive or welder that you used to use. In fact, I've yet to see a universal cement adhesive or glue. They all have their strengths and weaknesses. The trick is to learn what each product can and can't do, then use the one best suited to your particular requirements.

What's left? Epoxies. These are two part products where you have to mix equal parts of the two components together before they'll begin to cure. One more time, there's a wide variety of these little boogers, most of which you'll find in hardware and automotive supply stores, as well as hobby shops that cater to radio control modelers. Liquid, semi-liquid, putty (including Milliput for the modeler), they come in all forms. Some cure in five minutes, others can take several hours. Some even have a metal base for use on pipes.

Yep, things have certainly changed in the cement/adhesive/glue area. Used to be that your choices were real simple. Depending on whether you were building a wood or plastic model, all you had to do was tell your father to pick up a tube of Ambroid, Testors or Revell 'S' cement and you were done. Today you need a catalog to even list all the available choices, never mind figure out which one will really work best for you. And keep in mind that I haven't gone near the various specialized woodworker's glues that are occasionally useful to the plastic modeler.

See y'all next month.