Convertible-Top Replacement: What Goes Into Rejuvenating The Canvas
Dec 1st 2018
Convertible-Top Replacement: What Goes Into Rejuvenating The Canvas
By: RANDY BOLIG | Chevy Hardcore | November 29, 2018
What else can give you a bigger sense of freedom than cruising around town, down the interstate, or even a country road with your car’s roof folded down and the wind blowing through your hair? In fact, have you ever seen an unhappy person driving around in a convertible?
Unfortunately, that “canvas” roof doesn’t last forever. Years of the sun beating mercilessly on the soft material and the many up-and-down motions will inevitably take its toll on that material. When the deterioration begins, you can either leave the top in the down position and hide it, or replace it. If you’re planning a replacement, the folks at Hydro-E-Lectric want to help you take care of that and restore your drop-top wonder.
The largest issue we had to overcome, reared its ugly head before we could even begin. The aftermarket convertible-top framework didn't line up. James had to make metal pieces to attach to the leading edge of the frame to extend the edge outward from the side of the car.
The task of replacing a convertible top is not overly complicated, but it does require methodical planning and meticulous attention to detail. In most cases, it can take a professional 7 to 8 hours to correctly install and align a top – if everything goes as it should. For the install we’re showing you, things did not go that easily.
The C2 Corvette we are working on, came into the Hydro-E-Lectric shop with a new, reproduction convertible-top framework. Right away, installer, James Coloma noticed some issues that needed to be addressed. First, was the leading edge of the frame in the door area. He remarked that the rearmost bow was substantially wider than the area where the top tucked in by the door’s windows.
This necessitated fabricating a piece of metal for each side of the convertible-top frame that allowing the leading edge of the mechanism to have a smooth transition with the side material of the top. There were a few other small adjustments that needed to be made – not addressing these issues now would result in a sub-par installation when complete.
“In this case, adding steel to the side frame was needed on both sides to ensure a level contour from the rear bow to the side channels. If not careful, doing such amendments to the car can cause issues such as wind noise, leaks, or chaffing, due to the extra metal being present,” James stated.
Attach the pads and strips on left and right side of top frame using staples and rivets to secure. the pads and strips help protect the top, and also holds the framework bow in position.
I am quite confident that most enthusiasts could handle a convertible-top replacement with a little guidance, if armed with a few tips, the right tools, and a good set of instructions. It seems like a daunting task to take on yourself, and even if you decide to have a professional replace your top, no one will hold it against you. But, you should at least have an idea of what goes into completing the task.
Dry-fit the top material to the frame. Tops come fully sewn, so there is no stitching required.
Do You Have Everything?
Any time you are working on a convertible-top install – or anything for that matter – you should begin with an assessment of what parts you have and what parts you need. Doing this revealed the aftermarket frame issues we encountered, and allowed us to fix them before we started to install the new top material.
Tuck the back of the vinyl top below the rearmost framework-bow, keeping the plastic reinforcement above the tack bow. Using a tool, push the bead at the rear edge of the top into the inner channel of the bow. (Note: this was not easy. James made a tool to push the material into the channel and it was very tight.) Next, take the plastic bead that comes with the new top and the rear-bow seal, and push the bead into the channel with the weatherstrip. This holds the weatherstrip in place and keeps the material tucked in under the bow.
Tops can come in different styles. Some cars originally came with a vinyl rear window and some came with glass. Many cars that originally came with glass, often received vinyl replacements after the glass broke. The top being installed on the C2 was fitted with a vinyl rear window.
Test fit the front of the top and pull the material forward, working from side-to-side. Spray adhesive on the flaps located on the left and right of the vinyl top. Also, spray adhesive where the top aligns on the rear side-rail (the areas James had to modify).
Typically, every convertible top is installed in the same fashion. The top is stapled to the frame via tack strips. Depending on the age of the vehicle, the tack strip will be either pressed cardboard (’60s and ’70s vehicles) or vinyl rubber (modern convertibles). A replacement solution is vinyl rubber – which is actually better – because cardboard holds water and the top frame is metal and can rust.
Before you stick the top to the framework, staple the vinyl material across the header, working from one side to the other. Then, fold-in the glued tabs and flaps and adhere them to the frame. After that, pull the top frame forward – gently – and latch the top to the windshield.
"Keep your top up and closed tight, especially for the long term. – James Coloma"
The major tools needed to complete the installation are an air compressor, a good-quality staple gun, and we suggest a professional-quality glue from any upholstery-supply shop that can be sprayed from an inexpensive primer gun with a large-fluid tip.
Those are the primary parts and some of the tools you will need. When you are done, the top should be taut, and there should be no sagging. But, you don’t want it too tight, or it will pull out or tear at the staples. One trick to getting the top snug, is to work with the windshield latches disconnected and the frame elevated about 12 inches from the windshield. When the job is finished and the frame is lowered to the windshield and latched, the vinyl will be pulled tight. We’ve found that even professional upholsterers have to remove and re-staple a top several times before they get it just right – it is simply part of the process, so don’t expect to accomplish it the first time. Just don’t give up.
With the latches released, pull the rear window area of material forward so the material at the rear trim stick (above the rear window) is in the right place. Push the rear tack strip back as far as it will go. The bow pads are attached to this bow, so it can only go so far.
Tips For A Long-Lasting Top
James recommends that you never drive for long periods of time with the top down, without mitigating the possibility of chaffing, by using towels or padding. “Top material likes to shrink if kept in a loose/down position,” James stated. “So keep your top up and closed tight, especially for the long term.”
Staple the rear section (window area) to the trim stick. Start at the center and work side-to-side. When you get to the ends, pull the material outward to be sure there are no wrinkles. Unlatch the front of the top, and staple the upper part of the rear material onto the rear trim stick. Work across, keeping the material tight and free from wrinkles. Re-latch the front latches.
The top material above the side windows was too loose. James marked the top with a pencil, removed the staples across the front and readjusted the top. This just shows that it even takes professionals more than one try to get it right.
Washing your convertible top regularly with soap and water is sufficient on most occasions. Make sure to park your vehicle in a shady spot and let the top cool before wetting. Use a hose with good water pressure and rinse off any residue before you begin. In most cases, you can simply use the same soap that you use for washing your car, as long as it doesn’t contain harsh chemicals.
Use a Special Convertible Top Wash
For the best convertible top care, apply a solution that is designed specifically for your type of convertible top. Do this at least a couple of times a year, or more frequently if your convertible top is directly exposed to sun and elements. Lightly spray or spread the top cleaner and scrub with a soft bristle brush or a sponge. Make sure to rinse thoroughly until the water runs clear.
A piece of trim – called a wire-on – covers the staples above the rear window. Align the wire-on and put one staple in the center to hold it. Then, attach one staple at one end. Keep it straight and tight as you fully staple across its length. At the ends of the headliner bow, follow the curve of the bow to the ends of the area you are covering. Cut off any extra length of wire-on. Finally, fold the wire-on over itself and use a rubber mallet to flatten it down across the bow, and place the arrow heads (end-trim pieces) onto the ends of the wire-on material and screw into place.
Apply a Top Protectant
Periodically, using a special convertible top protectant will keep your roof strong and assist in preventing damage such as tears or fading of the material. Select a product that is designed to keep color and texture in good condition, as well as repel dirt, grease, and oils from the road.
More Than Just “Canvas” Tops
Hydro-E-Lectric carries more than just ready-to-install convertible tops. If you’re looking for convertible-top cylinders, motor pumps, hoses, weatherstripping, latches, boots, well liners, manuals, relays, window cylinders, window motors, header bows, rear tack-bows trim sticks, and more, they have it all for U.S.-made cars from 1940 through present day.
Don’t Use Glass Cleaners
If you have an older model car with a plastic window in the convertible top, take special care when cleaning the windows. Often, glass cleaners use harsh chemicals that may not be safe for plastic. This can scratch and otherwise damage your window. Use a product specifically designed for your plastic windows, to reduce scratching and protect the plastic from discoloration.
At the header bow, place the covered header-strip in place and staple across the front bow. The header seal snaps into place on the metal bow.
Repair Your Broken Convertible Top
If you are experiencing problems with your convertible top, there are a few things you can check to see if the problem can be easily fixed. Often, malfunctions can be taken care of quickly to help maintain the life of your top. If the top is powered, and simply not moving – whether open or closed – check the switch to make sure it’s set to automatic, and make sure all fuses associated with your roof are in working order.
If switches and fuses are properly set, check the hinges, roof brackets, or top struts for bends, breaks, or improper alignment. You may also want to check the plastic or elastic straps. Hinges, brackets, or straps can usually be easily replaced or repaired quickly.
I’m not going to tell you that installing a convertible top is easy. I will, however, tell you it can be done at home if you take your time and think about what needs to be done.
In addition to selecting proper cleaners that won’t damage the material, you should also make sure to immediately clean off substances such as bird droppings, road salt, and spills. Don’t ever place anything heavy on top of a soft roof. If you live in a climate where snow can accumulate, be sure to remove it as quickly as possible.
Weight can put undue pressure on the frame and metal structure of the roof. After washing the roof, or applying cleaner or top-coat protectant, leave the roof up and let it dry completely before putting it down to enjoy the road. This will prevent any chance of building mold or mildew that could harm the material.
Now that you have a basic understanding about what it takes to replace a convertible top, maybe it’s something you want to tackle yourself? Regardless of whether you do it or have a shop complete the task, Hydro-E-Lectric can get you all the parts you need to get your top looking – and working – like the day it was new.
ABOUT THE AUTHOR
Randy Bolig has been working on cars and has been involved in the hobby ever since he bought his first car when he was only 14 years old. His passion for performance got him noticed by many locals, and he began helping them modify their vehicles.