Friday, January 14, 2000

Vertically Oriented Strike Indicator

Originator: Catch Cormier

Applications: freshwater, saltwater

Remarks by Catch Cormier:

While attending a popper class conducted by Kirk Dietrich in 1991, the concept of the "popper-dropper" was mentioned for saltwater.  A Clouser Minnow or other weighted fly is suspended under a Popper.  After trying it out, I noted two faults: (1) the depth of the dropper fly couldn't be adjusted, and (2) the dropper section kept getting tangled in the popper hook.

So instead of using a popper, I simply took a styrofoam perch float, cut it in half, drilled out a concave face on each half, and made them into the fly rodder's popping cork.

Since use of a "perch float" was unacceptable to some fly rodders, I gave this creation the name "Vertically Oriented Strike Indicator" (VOSI). Kind of like "gambling" is illegal, but "gaming" is okay. Besides, unlike a perch float, the VOSI requires the correct leader formulation to insure the proper displacement of the trailing fly and it's action in the water. It's all in the 14 page operations manual.

Seriously, the name refers to the fact that it hinges the leader and fly into a vertical orientation, ie, about 45-90 degrees to a floating fly line. The vosi sits horizontally in the water, but when a fish strikes, even just a nibble, it bobs into a vertical orientation. If the cork goes under, it's time to set the hook. For freshwater, the pointed end faces the fly line. A slight twitch is all that's used. In saltwater, when fishing for specks, the concave (wide) end faces the fly line. Here the fly line is stripped, not twitched. A good hard strip causes the VOSI to pop, enticing specks to investigate the fly beneath. The plastic pin is always inserted into the narrow end regardless of it's use.

A few years later, there was an article by Lori Tucker-Eccher in American Angler magazine which explained why suspension methods are so productive for the flyfisher. Consider the sacalait, a.k.a. crappie or white perch. It lives and feeds tight among brush piles, tree roots, rocks and other structure. Success with crappie depends not only on placing the fly in it's feeding zone, but keeping it in the zone for a prolonged period. The VOSI serves to place the fly at the proper depth without the need for constant stripping, thus insuring maximum exposure to the fish. But in addition, slight twitches of the fly line, and consequently the VOSI, move the fly in a vertical fashion. An enticing action that no species can resist.

For freshwater, the most popular fly as a dropper is either a jitterbee or fluff butt. My friend Mark Hester has had great success using the vosi with a fluff butt tied on a jighead (leadhead). This allows the fly to suspend 90 degrees to the float and still keep a horizontal orientation. In saltwater, the most popular flies have been the Clouser, the EP Spawning Shrimp and several varieties of charlies. Though any fly with weighted eyes will work.


Perch floats in either 1 1/2" length or 2" (slightly wide) length. The larger corks are almost always used for saltwater, for choppy conditions, but require a higher weight rod to cast. The smaller floats can be cast with as little as a 3 weight, but a 5 weight is recommended.

A dremel bit tool, conehead sander.

Xacto knife.

Sanding paper, 400 grain is good.


Using a Xacto knife, cut the perch float in half. Most of these floats come with a white end and a red end. If you plan to make Kirk's Perch Float Poppers, save the white end for that purpose (it eliminates having to do a primer coat).

Take the Dremel bit and bore out a cup face in the half-floats. Do this by hand - using the Dremel tool is not safe, and will eat away too much of the styrofoam.

If you wish to create a slit, take the Xacto knife and carefully cut lengthwise to the center. Take the sandpaper and pass the edge into the slit, then sand out the slit so it's wide enough to accept your leader.

If water is choppy, then a larger size vosi will work. If you have trouble making the vosi pop in saltwater, then modify the plastic pins. At the wide end of each pin, add a few wraps of lead weight and cover with thread, then epoxy over. This sinks the vosi just enough to make the cupped face "grab" water when stripped.