Rainy's Blog

Selecting Foam for Fly Tying
Jesse Riding


We started seeing foam added to flies in the 1980’s. Until then, we were doomed to go to drastic measures and lots of false casting to dry our flies. This was before the boom of synthetic materials and the invention of the craft store and industry. Fortunately for us today, there are a variety of options both for those that want to craft their own shapes and designs or those to just simply want to throw on a pre-fabricated head on a hook shank to upscale simple fly dressings to a really sharp-looking fly. Nowadays there is a foam shape already designed for nearly every major application from trout to bass to saltwater.

The nice thing about pre-shaped foam bodies and heads is that all the work is done for you. You can now add a buoyant, super durable, head or body to your fly compared to the traditional alternatives of trimmed hair and other animal products. You can easily lash on a foam body or simply dress the hook and then slide the popper head over the eye of the hook to cover all your thread wraps for a nice clean look.

We could go on for hours about the chemistry and science of the different types of foam, but there are only so many times you can say the word Polyethylene or talk about the cross-linking process of different polymers before you get bored. It is also a waste of good fishing time!!!

For the sake of this article we will only say that foam comes in two main types: “open cell” and “closed cell”. Closed cell is buoyant and accounts for 99% of the foam used in fly tying and open-cell is foam that absorbs water (like a sponge) and helps to make your fly sink. For the most part, foam is added to a fly to add buoyancy to your fly. The only real scientific variable is density.

HOW TO CHOOSE YOUR FOAM: First, determine your application…

Density, or another way to explain it would be is its softness and/or flexibility, is the first thing to consider when choosing what foam to use. You need to match this up with your desired application or design. Do you need the foam to be soft or would you prefer it to be rigid? Too soft and the foam may tear. Too hard and the foam may dent. You may need to wrap the foam and need it to be soft, or you may be shooting for a durable, “bullet-proof” option for aggressive or toothy fish. Second, you need to consider thickness or shape. Does the desired foam with the right density for your pattern also come in the right size, shape, or thickness? Lastly, color. Does the foam with the right density and thickness or shape come in the right color? You can always paint it yourself so this is a last and optional consideration. Nearly every foam that I have worked with readily accepts paint of all kinds, various glues, epoxy, etc. with little to no side-affects.

Another question you have to ask yourself is: “What hook am I going to use?”. This may often limit the size and other shapes that you have to choose from. In today's world we have access to almost every hook model from every hook manufacture so this may not seem like a very big deal but sometimes it is hard to find the perfect hook for your fly design. When choosing a hook, the two major factors to consider is shank length and hook gap. Based upon the design of your fly you may want a long shank for more materials or to put the hook point further back in the fly profile. Or you may want it to be a short fly and therefore you will just need enough to put the popper head on. Next would be the hook gap. This is critical as this is the part that actually catches the fish so it is important that you not only tie the fly with a proper hook gap, but choose the right foam body or head and hook to maximize your gap so that you will be able to properly stick the fish. Also, straight-eye hooks are optimal and highly recommended for sliding popper heads onto the hook. Specific hook size should not really be a consideration as there are so many hook manufacturers and models to choose from and their hook size nomenclature is all over the place so you really need to physically match up the hook with the desired foam body or head. Don’t spend time worrying about whether or not the hook on your new cool popper is a true #1/0. If a size #2 works, go for it.

Many hook manufacturers make and recommend kinked shanks for foam poppers and these do their job for sure, but do require you to slice the bottom of the popper head (the only part the fish actually sees by the way) and leave a nasty scar that is often very undesirable. At Rainy’s Flies, all of our popper heads are hand shaped and a center shaping hole is left in each popper. However, this is not the hole that is recommended to put the hook through as it will most likely minimize your gap. A new pilot hole is recommended to be put in the popper head using a bodkin or other similar instrument closer to the “bottom” of the finished popper. You then can simply add a thread base and glue to the shank and slide the popper head over the eye of the hook and butt it right into any materials you have tied on and cover any unsightly thread wraps in the process. Once the glue is fully cured, due to the high density of the foam, your popper head will be secure in place and won’t spin. Gluing the popper head onto your hook should pretty much be one of the last steps in tying your fly.

Try these tips in selecting your next foam fly project for optimal fishing success and professionally looking tied flies.