Metal Vs. Fiberglass Bodies
It seems there is always some discussion going on about the merits of “metal” versus “fiberglass” bodies. For the most part what I see is a lack of the knowledge needed to make this decision.
Let me start by telling you my background includes training and working in the auto industry as a body man. Although it kind of gives away my age, I can tell you that my experience began in what I refer to as the “pre-bondo”era. That means I was trained to actually “straighten” metal without covering the damage with fillers. Not to go into too much detail, I started my career in a shop specializing in Mercedes’ and Jaguar’s. So, “almost straight” wasn’t good enough!
Along the way I got involved with fiberglass products. I remember sometime in the ‘60s a friends’ father coming home excited to show us a piece of “fiberglass” tubing that had just appeared on the market. He had to show us how he could deform it in his vice and it would spring back to its’ original shape when he opened the vice again. That wouldn’t happen with a metal tube.
Over the years I have had the opportunity to work with a number of fiberglass shops and have learned many of the processes and materials for different applications. One of my hobbies is restoring pre-1960’s fiberglass boats. It surprises me sometimes how poorly even a top end boat was just thrown together. I believe the problem was both a lack of complete understanding of the early fiberglass materials and trying to build to a (low) price.
A lot of early as well as low cost fiberglass products are built using what is called the “chopper gun” process. This means using a special gun that draws a string of fiberglass material off of a spool and chops it into short pieces as it passes through the gun. At the same time the gun is spraying a stream of fiberglass resin that mixes with the chopped fiberglass material and then is blown into a mold. This mixture is then brushed/rolled down into the mold to get it compacted into a thin layer and to remove all of the air bubbles. If air bubble removal is not done thoroughly and properly one ends up with voids between the outer gel coat and the fiberglass.
It has been my experience that about one in ten people doing this work really know how to roll this material out without ending up pushing it around creating an inconsistent thickness in the fiberglass part. Some shops compensate for this inconsistency by just adding another layer or two. While this solves the problem, it also makes the part heavier than needed.
Despite the obvious problems with chopper gun application, it works well for thicker hulled boats and other applications requiring a thick end product. It has also worked well in the motorcycle accessory industry for years as evidenced by all of the fairings, saddlebags, top boxes, trailers and sidecars having been built utilizing this method. Unfortunately, I have proven that a good fiberglass fairing and bags can provide as much protection as metal crash bars when a bike goes down. A person I know was coming to an event and hit a black bear at sixty miles per hour with the nose of his California Friendship III sidecar. The bear rolled almost completely over the sidecar. Aside from the paint damage, he only had to repair the broken hinges on the nose canopy. The fiberglass had absorbed the impact with no structural damage.
Because we strive to make a better quality product, we do not use the “chopper gun” method to build our products. We insist that our products be “hand laid” using better quality materials and resins that are usually reserved for building molds. Because molds are subjected to repeated high temperatures during the curing process of the parts, they use higher cost resins to combat the heat and to maintain their shape. Using these materials in our products means they can be left outside in the Arizona sun without changing shape like what can happen with less expensive materials. Hand laying also allows us to easily strengthen any areas needed and maintain the thickness of material needed to keep the product strong and light. We have the knowledge and experience to properly use this technology.
Over the years I have owned many different sidecars, some metal and some fiberglass. Quite frankly for the most part what the sidecar it is made of has little or no impact on whether or not I would buy it. If I had a choice it would probably be done in fiberglass. Vibration seems to be the enemy of metal bodies and fenders. We have replaced with our own fiberglass parts, a number of metal fenders that started to crack around their mounting points and eventually split and fell off. We have also had to weld cracks and strengthen areas around metal body mounting bolts. Steel bodies are easily dented and aluminum more so. You can kick a fiberglass body all day and aside from damaging the paint, the only other damage will be to your foot. I once had vandals pile a Kenna sidecar with garbage and light it on fire. Fortunately the overhead sprinklers in the parking area came on and put out the fire. The windshield had melted into a puddle on the floor and there was enough other damage that I decided to replace it. While trying to break up the body, I made the mistake of trying to split it with an axe. Instead of going through the fiberglass it bounced back at me and just missed my head. I WON’T try that again! While I can obviously fix any damage to any material, I find fiberglass harder to damage and easier to fix if you do damage it. I can only remember fixing one fiberglass sidecar that was involved in a slide down a slippery hill and a sudden stop at the bottom against a sign post. No, it wasn’t mine.
The manufacturers of the motorcycles you probably ride have been using plastic fenders and body parts for years and nobody questions that anymore. Sidecars have been made of wicker, wood, aluminum, steel and probably a lot of other materials. Since the appearance of fiberglass it has been used by almost all sidecar companies from the very expensive to the economy models. There are still a few metal models manufactured today, but for the most part, they are coming from China and other countries where quality doesn’t seem to be as important.
One last thought…Take a look down the side of a metal body and see if it is straight. If that matters to you, I look forward to seeing you in your new fiberglass sidecar!
Ride Safe!