How to amplify rattles in your flies. Now, embedding rattles into flies is nothing new. Borrowed from the booming clink-clank of art lures, tyers have been using rattles for years to target a variety of species. In the past decade some of the more hardened local salt fly-fishers turned to making their own from broken rod tips in an effort to create a specific sound for kob and leerfish and, to have a more durable product. (Here’s looking at you MC Coetzer and Conrad Botes, as always, we stand on the shoulders of giants).

LeRoy Botha and I have been using rattles in our flies for some time now. Mostly these are embedded in foam (using a variety of techniques) for amplification. By happy accident, I found that a Nerf gun bullet (being the father to two boys under 9, my house is littered with them) has the perfect hollow to hold a rod-tip rattle with the added bonus of providing the perfect base shape for a silicone mullet or interior of Sponge Bob or crease fly. So those are my favourite. Being the craftsman that he is, LeRoy ‘builds’ his own heads (more further down).

how to amplify rattles in your flies

LeRoy Botha’s ‘Bellend’ version of the Sponge Bob, with ‘built’ heads and embedded rattles.

Recently Platon Trakoshis did a very informative post on rattles, highlighting their benefits as well as various methods of attaching them. “When I’m fishing at night or in dirty water and I pick a fly, I give it a little shake expectantly,” writes Pla.

“When I hear nothing I feel disappointed and my confidence in the fly drops a tad. But if it rattles I hear Prince singing ‘Sexy MF Shakin’ that ass, shankin’ that ass’ which is enough to put a bounce back into my cast,” he says.



in which he alludes to the amp:

‘…for surface patterns is to embed the rattles inside the foam head. This protects the rattle but at the same time it seems to amplify the sound of the rattles, which is a bonus.’  HERE


To get ever-so-slightly techie, let’s have a look at exactly why it is:

“When the moving part hits the inner wall of a rattle it vibrates the rattle wall, creating a sound wave,” says LeRoy, who (aside from being a professional tier) pays the bills by playing music, so he knows the odd thing about sound.

“Now if all you have is the rattle itself, this energy is lost pretty quickly. Like a speaker cone without a box (or resonating chamber) or a guitar string with no soundboard to vibrate,” LeRoy explains.

“So – ignoring the other variables – the greater the surface area of a soundboard, the more effective a resonating chamber is at doing what it does.”


*sound on. Even my pup approves…

To paraphrase the science. A resonating chamber enhances the transfer of energy from a sound source to the air, like so: As an acoustic wave enters the chamber, it is reflected or bounced back and forth inside it. “The wave literally ends up crossing paths with itself multiple times, thereby combining and reinforcing it and increasing its intensity,” LeRoy says.


LeRoy’s ‘Hulkbuster’ a kob-fishing version of his Ironman grunter fly


Foam built around a rattle, then, (as long as there is direct contact between foam and rattle) acts as a soundboard encasing a multitude of little baby resonating chambers. Without the foam, the sound energy is quickly lost. But with it, it is multiplied almost exponentially before dissipating into the air, because the sound wave is bounced and reinforced by the massively increased vibrating surface area provided by the air pockets in the foam.

The thicker the foam, the greater the effect as the wave moves from the inside of the rattle towards finally leaving the foam casing.

As mentioned, I make my rattles out of broken rod tip bits, split shot and epoxy and find these fine for my needs. LeRoy has used broken rod bits in the past, but for the most part prefers to keep his rods whole, so his current method is a bit more refined.

Here’s how LeRoy builds his rattles:

Rattle parts showing stamped-out flat lead plug, moving part and tube.


Thin lead seal pushed-in half mm then superglued in place


Enough superglue to form a dome – proper drying time allowed between steps.


how to amplify rattles in your flies

Back end of rattle covered before tying tail