Over the years, foam has become a nearly indispensable fly tying material, with different offerings appearing on the market at a dizzying rate. If you can dream up something made of foam, it most likely already exists. Rather than look at all these different possibilities, let’s instead go back to basics and talk about plain, old sheet foam that’s available just about everywhere – from big box and grocery stores to your local fly shop.
Most of these fairly large sheets are 2 mm thick and come in every color of the rainbow, and then some. Rather than large sheets, fly shop foam generally comes packaged as smaller, more manageable pieces. They typically carry a variety of thicknesses as well, such as 6 mm, 3 mm, 2 mm, 1 mm and a super-thin offering commonly called razor foam. Each of these different thicknesses has slightly different characteristics and uses. But once again, let’s go back to basics and talk primarily about 2mm sheet foam.
Sheets can be folded, have a little bit of stretch or give, and can be easily cut with regular scissors or a hobby knife. Perhaps the most important attribute however is the fact that foam floats which means flies that incorporate it will also float. Because of this, foam is often used to produce flies that imitate terrestrials, such as ants, beetles, crickets and grasshoppers. But it can be incorporated into any pattern where extra floatation is needed.
For most applications, I like to start with even-width strips. These can be made on a cutting board using no more than a straight edge and a hobby knife. If you plan on tying a lot of foam flies, a paper cutter is well worth the investment and is capable of cutting wonderfully uniform strips. Cutting foam down into smaller more usable pieces also makes it far easier to store rather than hassling with large sheets.
Although you can cut sheet foam into various shapes, again, with scissors or a hobby knife, specialized cutters such as those from River Road Creations make the job much easier and help to produce more professional looking flies. Simply press down on the foam with the razor-sharp blade and you end up with a perfectly shaped and repeatable foam form. Cutters are available that produce a wide range of shapes and sizes. I prefer to do a whole lot of cutting at once, which allows me to focus more on the tying part when it comes to it. A hole punch is another great tool to have as it can produce hot spots or little indicator disks at a rapid rate. These too look more professional than those simply cut out with scissors.
Attaching somewhat slick foam to a slippery metal hook can be a bit tricky. I like to start with a heavier thread such as UTC 140 Denier. It’s both strong and doesn’t seem to cut into the foam as much as some other threads. I’ll add a fair bit of tension to my bobbin in order to make nice tight wraps. To help prevent slippage it’s always a good idea to start out with a substantial thread base on your hook. To further prevent slippage, you can add an additional slender piece of foam and bind it down really well, both up and down the shank. Any foam placed over top of this will slip very little, if at all. You can pretty much do the same thing by covering the shank with dubbing, which also makes the fly look more appealing from below.
To actually attach the foam to the hook, I like to correctly position it then take 2 loose wraps of tying thread, squeeze and compress the foam in my fingertips then pull tight on my tying thread to close the two prior turns down and secure the foam. I’ll then add a few more tight wraps as insurance. Even with the foam locked down in this manner, the connection is a bit tenuous. To correct this prior to tie-in, place a small drop of superglue at the tie-in point. Then repeat the placement, wrap and tighten procedure as before. The adhesive makes the connection that much more secure.
When tying in the end of a foam strip, a slight taper cut into that end makes the job much easier. Another thing to keep in mind when working with foam is that if your tying procedure heavily compresses the foam, as it’s done here, the foam will lose nearly all of its floatability.
Cyanoacrylate adhesives such as Zap-a-Gap or superglue work well with most foams. If you’re trying to stack two like shapes to form a stacked or multicolored body, getting them properly aligned can be problematic, with the results not up to par. Instead, try applying the adhesive to one sheet, placing another down on top of it and adding pressure to set the adhesive. You can then cut the combined sheets to shape with the end result looking much more professional.
Use different colors of foam to produce different effects, such as a fade from the dark back of a bug to the generally lighter underbelly. Foam also takes permanent marker exceptionally well. It’s fine to simply draw on it and maybe produce the look of segmentation like I’m doing here, but as with the cutting, I’ve found that creating a pattern on the sheet prior to cut-out makes the end result look that much more natural.
When tying with foam, don’t be afraid to use your creativity. Try folding, twisting, glueing or cutting as well as combining other materials. The possibilities are endless. Foam flies deserve some space in every angler’s fly box. They can be used when you’re pounding the banks of a large river with terrestrials in search of brown trout or pursuing little wild rainbows on a small mountain stream.