When winter winds congeal our northern waters, some fly fishers convert to winter oriented sports, some migrate to less frigid climes and some tie flies.

In fact, the current resurgence of fly fishing coinciding with a general interest in arts and crafts of alI kinds is making fly tying a popular winter leisure occupation. Materials, tools, and instruction books are available at most tackle stores and fly tying classes are becoming common.

As with any craft, there are certain rules and practices that, if allowed, will help insure a quality product.

First of all, avoid waxed thread for tying. Wax was originally used to keep silk or linen thread from rotting. With synthetics such as nylon, it offers no advantages and does have at least one definite disadvantage. Conventional fly tying cement will not penetrate wax so it can't properly seal knots tied in waxed thread. Regular varnish is the only cement that will and is hardly ever used today because of the several hours required for drying.

Waxed tying thread is presently being promoted by a few angling writers and tying instructors as a way of eliminating the need for half hitches in fly construction. Their theory is that several wraps with sticky thread will hold each successive operation in place good enough so that just a single knot when the fly is completed, should suffice.

Like so many other widely publicized fly fishing "innovations", this is an old idea recycled. It is a method used years ago for production of the cheapest lures and the net result was always flies that twisted on the hook or came apart in use.

Actually a competent tier can make a thread wrap and half hitch in less time, than it takes to make those several winds. Flies made with half hitches are less bulky and more durable. This is the way the best ones were constructed even when waxed thread was considered a necessity.

A fly tied without a suitable foundation beneath the rest of the material will also rotate on the hook. To prepare such a base, secure a hook in the vise and coat the shank with cement. Then spiral the thread around it from the eye to the bend. Half hitch at the start of the bend directly across from the barb. This is where the body will start. Coat this winding with cement. Starting the thread tight against the hook eye will insure there is no opening that could allow a fine leader to slip through.

Don't bury the hook's point when clamping it in a vise. This can crack or break a properly tempered hook. Always allow the point to protrude slightly and work around it.

If the pattern calls for a tail, tie it on with a couple of thread wraps and a half hitch at this time. Cement this knot. As a rule of thumb, a wet fly's tail is as long as its body and on a dry, it is as long as the hook.

Be sure to cement each half hitch and don't try to tie any material to bare metal.

Secure the body material to the hook with one thread wrap and a half hitch. If more than one item is to be incorporated in the body, tie it all on before winding the body but tie the piece that will be wound first, on last. For instance, if the fly is to have a wool body ribbed with tinsel, secure tinsel first, then the wool before proceeding with the winding.

Make all winds in the same direction. In this way each operation tightens the previous one. Winding first in one direction, then the other will make a loose fly.

Ignore any instructions that say reverse ribbing a herl or fur body will reinforce it. All this does is loosen the fly. If you think the material needs additional strength, twist some thread in with the strands before wrapping the body. Ribbing should always be wound in the same direction as the rest of the material.

Palmer hackle feathers are tied on by the tip and shoulder hackle by the butt. Tying a hackle feather on with its concave side towards the hook will make it wind with the fibers sloping backward. Tying it with the concave side out will make its fibers slant forward. Dry flies are usually dressed with two hackles wound back to back. This gives a sawbuck effect that helps them sit high on the water.

Prepare shoulder hackle by trimming the feather butts with a scissors instead of pulling out unwanted fibers. This way you can leave a row of fiber stubs on each side to help the thread grip the feather.

Hair is one of the most slippery wing materials. Saturating hair butts with cement before tying to a thread base and cementing the knot liberally afterwards makes for a durable wing.

Tinsel bodies should be coated with clear fly head cement to prevent tarnishing. Some shellback patterns have a feather section folded forward over a tinsel body. A drop of clear cement placed on the fold will keep the feather from fraying. Fast drying epoxy is ideal for this.

The yarn made by spinning fur on a short piece of thread for forming fly bodies is called "dubbing". The process of making this yarn is also called dubbing and a body made from it is said to be "dubbed".

The oldest way of making this, and still the best, is to wax a short piece of thread, place it on a small clump of fur lying on a rough textured surface like a trouser leg or a tablecloth, press down and roll until it is coated with fur. Rotate the fur covered thread between your palms to make a firmly packed fur yarn. Do this in one direction also. The dubbing should not increase the thread diameter greatly.

This is wound on the hook to make a fur body. To make the body more full, double or triple the strands of dubbing used, instead of trying to build up a lot of fur on one thread. If a fuzzy surface is desired, comb the completed body lightly with the slightly separated points of a scissors.

Dubbing wax is available in two different types. One is hard and non sticky, the other softer and tacky. Hard wax takes a little practice to learn to use, but is the least messy. It doesn't mat or discolor material.

The secret of coating thread with hard wax is to move the block of wax rapidly enough on the thread to generate a little heat. Once the thread is waxed, the fur adheres to it readily. There are other methods, but they all seem to result in loose, bulky dubbing and consequently less durable flies. Various dubbing hues can be obtained by using different thread colors and allowing them to show through the fur. The wax on dubbing thread will not interfere with cementing the tying thread.

Rough or chapped hands can snag and break thread. If this is a problem, tie with a bobbin. Don't, however, let it hang free between operations because the bobbin will spin and weaken the thread by untwisting it. A little hard paraffin rubbed on cracked finger sometimes helps also.

Dry flies will ride more naturally if they are tied with their wing sloping slightly forward. Dry fly wings should be as long as the hook shank and dry fly hackle, three quarters shank length. Hackle that is too long makes a dry fly alight nose down. Trimming a little off the bottom will usually correct this.

Tying with unwaxed thread, making a foundation to tie to, half hitching after each operation and cementing each half hitch will produce durable flies.

A whip finish is the best knot for tying off a fly. Always saturate the head with cement.