Like many amateur fly tiers, I own a Renzetti vise with a thumb nut or tightening screw as opposed to the cam design that is a popular among other manufacturers.

Renzetti now sells a vise with a cam design and a kit is available to upgrade your old Renzetti, but most Renzetti vises in use today have a screw system. The original models require the tier to finger-tighten a small screw to close the jaws on the hook wire. Next, a larger finger screw applies lever pressure to the hook to completely secure the hook in the vise.

Finger tight, however, is seldom tight enough, particularly with large saltwater flies, and the effort soon produces tender fingers from the knurled edges of the tightening screw.

Renzetti responded to complaints and now offers a cam option, but the upgrade costs half the price of a new vise. I have a home-grown solution that costs less than a dollar, and produces better results than a cam. It is based on the design of the common shop vise, which also has a screw-tightener, but uses a lever to help turn the screw.

The following materials are needed:
• a 2" bolt, 3/16" in diameter
• two 3/16" nuts
• a scrap of teak, or any other wood, approximately 1" long.
• a 3/16" drill bit.
• vise grips or a shop vise to hold the fly tying vise tightening nut for drilling

To modify your vise, place the tightening screw in a shop vise and drill the tightening screw with a 3/16" bit. Also center-drill a hole with the same bit through a short length of wood. Run the bolt through the wood and the tightening screw and secure the apparatus by tightening the bolt and nut. For a finished appearance, you may wish to coat the wood with a light coat of epoxy.