Tips and techniques from a veteran fabricator for flawless track-to-track enclosures.
When using track-to-track installation for enclosures, step-by-step instructions are helpful to achieve a proper fit, which creates a high-quality-looking job. Utilizing a track-to-track technique is necessary for today’s marine fabricator. A standard “snap” enclosure may take away from the look of today’s beautiful, sleek vessels. Some high-end boat builders are even building a track into their windshields that does not allow for the installation of snaps.
Track-to-track installation provides the potential to create an enclosure where the tension pulls evenly from top to bottom, without any wrinkles in the window curtains. Conversely, a snap-in-place enclosure under tension can show pull marks between the snaps, causing wrinkles through the window material.
I am going to take you through a track-to-track enclosure, from installing the track, patterning, cutting fabric and sewing to completion.
First, determine the location of the track to be installed. Is it to be installed on the windshield, on the radar arch or into the fiberglass hull?
Second, determine the type of track best suited for the project. You may be able to use a combination of types for an application.
Track types and their purpose
Flex Rail II is a PVC extrusion that is non-corrosive. It can be mounted on the top of a windshield, the edge of fiberglass or a radar arch, and can be bent around corners. Only small amounts of heat are needed to form it.
I apply 3M VHB foam tape (found at auto parts stores) to the back of the track to hold it in place while installing. It gives the track extra holding power, and provides a water seal between the track and the boat. To obtain optimum adhesion, the bonding surface must be clean and dry.
Use rubbing alcohol to remove residue and dirt from the boat and track. Wipe with a dry cloth. This provides a better holding area for the foam tape.
Stick the foam tape to the track and only peel back the paper on the foam for the area you are working with. Then apply the tape to the back of the track.
Predrill holes into the track just slightly larger than the shank of the screws (I use a 9⁄64-inch drill). Space holes 4 to 6 inches on straight edges and 2 inches on curves. Mount with stainless screws with a flat head and tapered shank.
If drilling into metal or thick fiberglass use #4 by 40 by ½-inch machine screws. In places like the corners of a radar arch where the fiberglass is really thick, drill and tap the fiberglass and install machine screws.
Costa track is a center-mount track with a heavy-duty PVC profile that maximizes load capability for large covers, biminis and track-to-track enclosures. It is designed to replace flange-style track and provides a more aesthetically pleasing result. It’s predrilled every 4 inches and can be heat-formed to most radii. The large channel opening allows the use of #6 stainless steel screws for a more secure attachment. Built-in countersink for the seating of screw heads allows welt to slide through unobstructed.
PVC awning molding is UV-resistant, non-corrosive, non-rusting and can be heated to form any shape. Secure it with flathead stainless steel screws.
Single track is the most commonly used for mounting windows in a track-to-track installation. A zipper is sewn to keder welt, which slides into the track, making an exact fit. Use #8 or #10 screws to fasten single flat flange or double track into the boat.
The anodized aluminum version can be bent, but it’s best used in straight applications. When cold bending aluminum track, I place a stainless spring (about 8 inches long) inside the track at the corner.
Double track molding (wall) is used when you want to slide panels past each other. The double track is installed at the top of the boat only, with single track at the bottom.
There are times when track can’t be mounted to the boat. Triple track was invented to extend double track capabilities to locations where fasteners are not available, like the crown on a hardtop, or if you want to create a sliding door off a bimini top. Triple track is available from Rainier Industries.
You can heat single or double track with a hot box, available from an electrical supply store. It has a heating element similar to that of an electric stove. It does not take long to heat the track, so be careful. A hot box provides even heating for double track if working in cold weather.
When mounting track to a hard top or radar arch into thick fiberglass, I drill and tap the fiberglass to make it easier to install screws to hold track in place.
When installing track around curves in fiberglass or a windshield, I use a heat gun and place a piece of keder welt inside the track after heating so the track doesn’t collapse while bending.
After you have the track installed, place marks on the track where you want to split your vertical zippers, making it easier to pattern the enclosure. Place double-sided tape to the edge of both top and bottom track to hold the patterning material. Cut off enough patterning material to fit one panel at a time, which allows you the ability to reach around the pattern to fit from inside the boat.
Secure the pattern material tight to the track. Look at it from an angle that it makes a C shape, which is the part your keder goes through to attach to the enclosure. Mark on your pattern on the very edge of the C that is the closest to the other C on the bottom track. Failing to do this can actually make your enclosure panel larger, resulting in a poor fit.
Mark where the vertical zippers go onto the pattern, and mark for necessary u-zippers. Mark the corresponding curtain number and the color of material, and as much other information as possible. Fit all enclosure panels one at a time on the same trip. Then proceed back to the shop. To process your pattern, lay the patterns next to one another to make sure that the top and bottom line up, this way one curtain doesn’t end up longer than the other.
Proceed making the enclosure panel the same way you would do a standard track-to-snap enclosure (except for the bottom edge where the border needs to be at least 2 ½ inches wide). Install your vertical zippers and add u-zippers, if needed.
On the bottom edge of the enclosure, cut the facing ½-inch longer than the line you have drawn for the track (this will allow your enclosure panel to cover the track for a cleaner look and will make the track last longer).
Zip all your enclosure panels together and lay them on a smooth surface. Pin or staple the enclosure panels to the table with tension between the curtains. Then sew the loop part of the Velcro onto the side of the keder that faces the enclosure panels. Be sure that when you sew the Velcro and zippers that you use the box side of the zipper (with the slider on it) down, and that you have two rolls of stitching on the zipper for added strength. Place ¼-inch double-face tape onto the zipper edge that is going to be sewn to the enclosure panel. Now take your keder that has the zippers and the Velcro sewed to it and lay it on top of the Velcro sewn onto your bottom edge of your enclosure panels. Be sure that the full enclosure is pinned down to the table and is tight.
Stick the zippers into place with ¼-inch double-face tape, unzip the keder from the bottom of the enclosure panel, and sew the zippers onto the enclosure using two rolls of stitches for added strength.
Finish look from the inside with zippers sewed to the track with two rolls of stitches in place.
Don’t sew the zipper all the way down to the enclosure at the very beginning. Leave 1¼ inch, which makes zipping the enclosure into place much easier. Sew two rolls of stitches onto the zipper for added strength.
The enclosure panel is longer than the keder welt. This allows the outside of the panel to cover the track, providing a clean look and protecting the track from the elements. PVC track is made to last outdoors, but by covering it you add life to the enclosure.