: Are there any differances between West Systems, System III or MAS epoxy
: resins as far as cost, ease of use, clarity, durability?

YES. And they differ in many more ways as well.

But, the differences are not so great that they make much of a difference in the final products we are building. The three brands you ask about are all among the best products for use for boatbuilding. The clarity, durability and ease of use is similar with each brand.

As for cost, you can easily compare the prices to see the differences.

Think of epoxy resins as being something like ordinary wheat flour. You start with a few basic types of wheat (hard or soft varieties) and grind that into flour. you can mix the two types of wheat in any proportions you wish, and also you can grind the flour coarsely or very fine. The miller picks the combination which gives you a mixture which would work best for breads, pastas, cakes, or for wallpaper paste.

Similarly, epoxy resins have a basic chemistry which is cammon between the brands. Sometimes the raw materials for competing brands of resins come from the same sources. Each manufacturer of epoxy resin then blends these basic ingredients in varying proportions to give their products the characteristics they believe the buyer will want.

Some resins are mixed specifically for one particular industry, for example, the aerospace industry, or the boating industry. Some epoxies are thicker and designed to be used as glues, while others are thinner and designed to be applied like paints. Some have added ingredients to resist abrasion, or pigments, or products which help the epoxy resist UV light. You'll see some epoxies marketed as coatings for concrete floors, and others used as coatings for kitchen appliances and bathtubs.

For all these varieties of epoxy the manufacturers have to blend their products to work at certain temperatures, have a certain strength, cure in a certain time--but stay workable for a certain time first, and so on.

Fortunately most blends of epoxy will work with holding fiberglass cloth onto wood, so even if you bought the worst possible odd-lot at some industrial close-out, you would probably be able to use it to build a boat that would float. In a worst-case scenario this junk might have a pot life of a minute at room temperature, and take a month to achieve a cure, but with some experimentation you could probably mix small batches in an ice bath (to cool it and prolong the pot life) and eventually get your glassing done.

Some people (and I think of the Seattle area) live where airplanes are constructed, and they have access to surplus amounts of epoxies which are designed for use on airplanes. These materials (at list price) would be much more expensive than the stuff we use for boats (the inspections and testing for materials used in planes would drive the costs up), and in many ways might be superior. The just aren't commonly available in small quantities at reasonable prices.

However, it is much easier to work with one of the major brands. They come with copious instructions and customer-service phone numbers. You can get additional components off he shelf at your local distributor, and the stock is fresh. You may pay a few dollars more for this, but a difference of $20 to $40 on the price of a $350 boat is not much.

There are also some very good resins sold as house brands. For example: Some boat kit or boat plan companies buy epoxy resins in bulk and repackage it into plastic jugs which they label with their own brand name. If you want to see an example of the economies offered by this, look at the price lsits at www.clarkcraft.com. If you buy 20 gallons you pay a bit more than $36 a gallon, but a single gallon is $52. The difference is nearly $16 for each gallon. It is easy to see that a guy with a 55 gallon drum of this stuff could mint money by pumping it into inexpensive plastic bottles, pocketing about $15 for every bottle he filled. While they are not the manufacturers of these resins, these companies may have a lot of experience with the resins they sell and can provide a lot of support and advice, too. I have no hesitation with using Clark-Craft's or Raka's resins for boat building projects. Like West, Sys III, etc. these are tried-and-true products, and designed for use in marine projects.

If you have to economize, don't go too cheap with your resin. You can save money in other areas. For example, you can build foot rests, and car-top racks, rather than buy them. Find a resin which is available near you and use it. You'll be happy. If none is available near you, order over the internet. But get this done before the weather gets to cold to ship the stuff. Epoxy resin does not like to be sitting in really cold temperatures. You don;t want stuff which has been frozen and thawed. It should be stroed at room temperature.

hope this helps.

PGJ