You need to be realistic about completing the bodywork yourself. Ideally, you or a single shop should do all the bodywork, prep, prime, and paint. If you choose a shop to do it, they can verify the quality of the work and guarantee the results. Completing the bodywork at one shop and having an owner participate in painting at a paint shop are two scenarios that rarely work out well. Bringing a completed, ready-to-paint vehicle to someone for paint is a tough proposition. No painter wants to take a chance on whether someone else has done bodywork and prep work correctly. It does not matter if you or a professional shop has done the work. Even if you tell the painter that there will be no responsibility on his part whatsoever, and that the outcome of the paint job is solely your concern, many paint shops are still reluctant because there are no guarantees.
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Let’s face it, bodywork is an art that requires patience and feel. You either have patience or not, and “feel” is something that’s developed over time. Experienced body repairers have a touch or feel for straight panels. They can feel a rise or dip in what should be a flat surface. They can also feel when body filler has a noticeable transition edge from the repair to the panel surrounding it. Some of us can quickly grasp this acquired talent, while others take years to fully master, if at all.
If you have trouble with feeling the wavy panels, blocking shows you where the spots are. Blocking refers to taking a long straight wooden or plastic block, applying sandpaper to it, then using it to sand panels. This finds any high and low spots in the panels. The unfortunate part is that you may spend plenty of extra time and body filler taking the waves out until you get the “feel.” Experience really pays off here, and this is why professional body repairers have a distinct advantage.
Professional body repairers also invest continually in the latest products, tools, and equipment to hone their craft. This gives them another advantage in using the latest technology in tools and repair techniques. The Environmental Protection Agency restricts the use of many of the early chemicals and products, and this is another reason why the cost of owning and running paint and body shops is so high. Cheap estimates equal low-quality work, and there is no way to do the job correctly without paying a reasonable price for it. Low-balling an estimate to get work in when every other shop is considerably higher, means the work will either be lower quality, or you will be hit with a supplemental estimate.
Be sure you are comfortable with your decision of how much you farm out and how much you do yourself.
Components to Consider
Let’s begin with the birdcage, which is the steel cage that surrounds the passenger compartment. It is where the Mid-year fiberglass body panels are attached. Coupe and convertible birdcages integrate the windshield frame into the assembly. Coupe birdcages are stiffer than convertible cages because the roof structure connects the windshield frame to the rear section.Major fiberglass body panels comprise the exterior to avoid as many visible seams as possible. The roof (coupes), upper rear surround panel (convertible), and front surround panel comprise the majority of the body.
Fenders and upper surrounds are bonded together with bonding strips to reinforce the body and seam. Fender break points start about an inch below the upper surround, following the crown.
Doors have steel framework with fiberglass skins. Working with the Corvette fiberglass bonded panels is quite different than repairing metal panels. You don’t unbolt fenders for replacement, which many do it yourselfers are familiar with.
You need a good idea of what repairs were done over the years and this is why all the paint was removed. A detailed inspection gives you a good indication. Make a plan of attack and stick to it. Once you know which structural parts of the body need to be repaired, you can proceed with the restoration.
With the chassis out from under the 1963, I raised the body up on the lift to do a thorough inspection of the under-side. I found some hidden, unknown fiberglass patchwork had been done at the rear of the car. It appeared that years ago, someone had spliced a rear section of another car to the upper roof panel. The center repair seam was located over a frame crossmember, and it would have been difficult to find with the chassis in place. That is, of course, until the paint stripping phase began.
I also uncovered this splice seam on the passenger side, going down into the side fender. Butt splices like this require specific repair procedures or they haunt you until the repair is correctly done. Cracks develop along the splice seam from road vibrations. The edges of the butted fiberglass panels become visible as body filler shrinkage occurs. In all cases the body filler shrinks in the space between the fiberglass edges, causing a noticeable line. Fiberglass must bridge the splice seams to prevent noticeable lines as the body filler shrinks. This area needs major fiberglass work.
The underside inspection revealed another area of concern: the passenger compartment tub had broken loose from the upper surround. I had not noticed the compartment tub bond issue from the interior, so removing the body was the right choice because it was very obvious with the body lifted. This is significant because road noise would be heard and air would flow unchecked through the passenger compartment.
I also found what appeared to be all- metal body filler used for bonding the body panels together. With this type of problem, you need someone with experience to help make the right decisions. Does all-metal body filler suffice for panel bonding? All-metal body filler was devised to strengthen the plastic filler commonly used and to inhibit water intrusion. I am concerned with the bonding strength of the all-metal filler. Does it perform as well as the prescribed fiberglass panel bonding adhesives?
Although I’ve been in this business for years, this was something I had never seen. I consulted with Al Sowash, who ran the body shop at Eckler’s Corvette Service Center in the ’90s. Al inspected the Midyear to determine the best solution to this problem. This Midyear had multiple experts discussing its fate. My next call was to Seth at Lucky’s Customs to let him know that Al would be coming by to take a look at the project in the coming weeks. After a through inspection it was determined that someone had indeed used allmetal filler. To be safe all of the suspect filler was ground out to be replaced with fresh bonding adhesive. By now you are probably wondering, why are they going on and on about this bonding adhesive and filler that was used?
This body filler issue is important because body fillers shrink over time. Also, fiberglass bodies show more of the effects of body filler shrinkage than do metal bodies. When a fiberglass seam or hole repair has been incorrectly repaired, it eventually shows up and is noticeable through the paint. Even when performed properly, there is a possibility that the seam or hole will show up after a long period of time.
You may have seen minor imperfections while looking at really nice Corvettes at car shows. Then you may have wondered, “Why is there a divot here and there, or a sunken line running alongside the fender where the upper surround meets the side fender?” This shrinkage phenomenon is seen more often in the South because heat certainly brings out the worst in any questionable repairs.
You don’t want to smooth a body and eventually have it show every repair that was made. Cracking occurs when a fender or inner support panel comes loose due to poor adhesion. The best possible techniques must be used to minimize shrinkage and fix loose panels. General Motors and AO Smith supplied bodies that used a specific bonding adhesive, but not “bondo,” to adhere the panels to the birdcage.
The story is that asbestos-reinforced resin bonding adhesive was used in the early years of Corvette panel assembly. No one can verify when this lethal mix was used, or if it was used for sure. Multiple sources have said that Midyears have been assembled with this bonding adhesive. In addition, no one seems to know for sure whether all of the 1963–1967 Corvettes were done this way.
The use of asbestos also has not been absolutely verified, but it makes sense to be very careful during sanding or grinding. Wear breathing protection and contain and dispose of materials properly.
I need to find out how many other repaired areas are lurking under my ‘63’s aged paint. I cannot stress enough how important it is to remove all the paint down to the raw fiberglass because the best surface for primer and paint adhesion is raw fiberglass.
I once had a Corvette painted for a customer, and the body shop insisted that they had the perfect primer-sealer that allowed them to keep the old, underlying paint in place with minimal sanding. I urged them to rethink the job and quote it with complete paint removal.
After it had been painted and before I finished assembling the exterior pieces, door handles, etc., the paint was lifting. What made a bad situation worse was that the new “silly putty” paint took nearly 40 hours to remove. In some areas (not near enough) where the urethane and underlying paint were compatible, it came off easily in with a razor blade. Consider yourself warned; don’t make a similar mistake.
You can use abrasives or chemicals to strip the paint. First, you don’t want to cut into the fiberglass panels. But some won’t chemically strip the paint because they fear chemicals will leach into the fiberglass and prevent proper paint bonding. Done properly by the directions, chemical stripping yields good results. With media blasting, plastic bead or baking soda are most popular for fiberglass bodies. The plastic bead process removes most of the paint without damaging the fiberglass, but I had to sand quite a bit to remove all the remaining paint. The blaster said that they could remove all the paint, but they were hesitant because fiberglass damage could result. Soda blasting is less abrasive on the fiberglass, but sanding is required to get all the paint off.
Many people are not aware of how important the steel birdcage that sup-ports all the fiberglass panels really is. Water leaks are inevitable and cause the birdcage to rot away slowly. With the birdcage hidden away under fiber-glass panels, extensive metal damage can occur unknowingly. Rotted bird-cages cause body panel flex and eventual cracks. A dead giveaway would be corroded rain gutters that direct water away from the door sills. The deteriorating gutters let more water intrude into the bird-cage damaging the metal components underneath the rain gutters. If you find severely corroded rain gutters you should remove the door sill fiberglass panel to check the extent of the damage. Fiber-glass panel removal is shown in the front end servicing portion on page 52.
Our project was typical with one severely rotted rain gutter with some minor underlying birdcage damage due to water intrusion. Reproduction rain gutters are available to avoid the need to fabricate an elaborate metal object. The majority of underlying birdcage steel pieces are not available and require custom fabrication. Fortunately, the birdcage pieces are relatively simple to fabricate. Next we move on the windshield area for additional metal structure inspection.
My next area of concern is removing the windshield, to check its frame. Old-school windshield sealing techniques were used on the Midyears, making them susceptible to leaks. The use of metal windshield trim clips on the metal frame allowed corrosion to start almost immediately. When the stainless-steel trim was installed, it often scratched the painted metal surfaces, causing corrosion to form. As the corrosion worsened, perforations allowed water to get inside the windshield frame and posts and caused unseen damage. My project had some damage, but not much in comparison to corrosion damage I have seen on other Midyears.
Chances are good that there is some windshield frame rust/corrosion and perforations to repair on even the nicest of Midyears that require restoration. Complete sections of the windshield frame may require replacement, or you may get lucky and just need a metal patch here and there.
I have seen plenty of Southern cars with severely rusted windshield frames and no chassis rust whatsoever. The ’63’s chassis was ready to fall apart as a result of corrosion, yet the birdcage and windshield frame were in very good condition.
Do not expect that all Midyears from the North have the same rust/corrosion concerns. Many have much more extensive rust damage that requires far greater repair work, and it’s difficult work to complete.
Personally, I would much rather change the chassis than delve deeply into the birdcage or windshield frame. Complete windshield frame or section replacements require extensive work and major fiberglass panel removal. Planning for this saves time and money. If the windshield frame is severely corroded, you should work on that while the front end is off the body.
Never use resin that has passed its “best if used by” date because older resin tends to gel and doesn’t flow as well as fresh resin. It’s also easier to work out the air bubbles during application. You need to precisely mix the hardener with the resin or you may run out of hardener. When the fiberglass resin and hardener mix, a chemical reaction takes place creating heat—a lot of heat. You want the finished fiberglass sandable within two hours. Any sooner and chances are you will not be able to lay the fiberglass mat-ting down and remove the air bubbles completely. Longer set-up times can leave you with weak fiberglass that never fully cures. The best policy is to contact a body and paint supplier to purchase fresh, high-quality materials.
Consistency is essential when mixing the prescribed ratios of hardener to resin. Stick to the manufacturer’s recommended mix ratio, application temperature range, and cure time. Another concern is careful preparation. Strong, dependable fiberglass panels require using 36-grit sandpaper to roughen the bonded surfaces. You need to have your materials ready to mix, matting to install, and tools ready. Do not forget to wear gloves and have some clean-up solvents nearby.
With materials nearby, you are ready to tackle seam repairs. The goal is to bond two separate panels of fiberglass, making them one piece. The repair procedure illustrated here should be used anywhere two pieces of fiberglass are spliced together. If done properly, the repair remains undetectable for the duration of the Midyear’s life. Time is the crucial factor, and you have to apply a few layers of fiberglass mat before the fiberglass resin kicks off. Fiberglass resin takes about 15 to 20 minutes to start to thicken. Once the resin activates, it’s set and you cannot make changes. You have to grind out any areas that are suspect and start again.
Next to be addressed is a really tough fiberglass repair under the left rear fender. Working horizontal and vertical surfaces out in the open are good places to learn. Repairing major broken structural fiberglass can be difficult because of impaired accessibility. In this particular case, I have a complete blow-out at the left rear inner fender. No one ever gets to see the work put into the area, but it is very important structurally. I could spend the better part of an afternoon properly repairing this section of broken fiberglass. Back-up molding panels (which take considerable time to fabricate) are required to form the missing sections of fiberglass. The previous repair was done quickly with some pieces of fiberglass quickly glued to the area, then covered with undercoating to hide the mess. An area like the left rear body mount has to be repaired with integrity in mind. The same basic procedures are used to form and reinforce the area. That is my next area to attack and conquer.
Earlier, I exposed some corrosion damage at the driver door latch area in the jamb. I removed the door jamb fiberglass panel at the latch area to see how extensive the corrosion was. Luckily, the damage was minor and required only one small piece of fabricated steel. These pieces are not available and must be fabricated. If you do not feel comfortable trying metal fabrication, check out a street rod or restoration shop. Make sure you bring all the pieces you possibly can and understand how they go together. The shop can then make a piece close to what you need per your sample. This is the only area that requires any welding, so you shouldn’t need to go out and buy a welder. The next few photos show you how I handled the birdcage repair.
Fiberglass Panel Replacement
Fiberglass replacement panels come in two forms: press-molded, and hand-laid. Press molding requires an inner and outer mold form. The inner and outer molds are pressed together under high pressure, resulting in smooth surfaces on both sides of the fiberglass panel. The press-molded process is extremely time consuming, which in turn raises the cost. Hand-laid panels are pretty much self-explanatory: Fiberglass matting is laid into the mold, then fiberglass resin is applied. Of course, you can smooth the inside of a hand-laid panel to look like the press-molded pieces, but it takes a considerable amount of time to do it. NCRS Corvettes are required to have press-molded panels; however, hand-laid panels with the bonding strips installed are fine for fun driver cars.
My ’63 needs major front end panels or possibly a one-piece front end assembly. The 1963–1967 Corvette front end consists of three pieces: an upper surround and the two side fenders. Bonding strips were used to put all three pieces together. To make assembly easier, a one-piece front-end, hand-laid mold was devised. Bonding strips should be installed to strengthen the one-piece front-end assembly. I mentioned earlier that the side fender-to-upper surround bonding seam distorts over time. One advantage of using the one-piece front end is that there are no seams to worry about down the road. Another advantage is that the installation of the one-piece front end takes less time.
In my case, I am using a hand-laid, one-piece front end to save money and time. Hand-laid fiberglass has noticeable chopped fiberglass strands on the inner surfaces. I will install the correct bonding strips to prevent wheel lip cracking. At first glance, the front end looks correct, even with the hand-laid fiberglass strands. The bonding strips are really there for reinforcement and should be used on whatever front end you decide to install. If your front end is fine, but the wheel lip is damaged, you should replace or repair the bonding strips.While I am working on the front end, I need to install inner fenders, since mine were in rough shape, with pieces missing from crucial areas. Take a good look around the hood hinge and hood prop area, which become damaged from even a light frontal impact. Repairing the inner fender in this area is possible, but it may come back to haunt you. Since the hood hinge and prop area of the inner fenders are under high stress loads, repaired cracks almost always return with a vengeance, far surpassing the original cracked area. At this point, it may sound like I cannot make up my mind. I am going to use press-molded inner fenders instead of hand-laid pieces. The press-molded pieces are easier to install and the price is close to the hand-laid pieces. Both the inner and outer surfaces of the inner fenders are actually highly visible, unlike the unfinished interior of the front end itself.
Fiberglass Panel Removal
Removing any fiberglass panel is not for the weak-hearted:
You must break loose the bonding adhesive from the panels. Hearing the crunch of fiberglass as you break each seam loose can be unnerving. To make matters more challenging, you must remove the piece to be replaced with-out breaking the bonding flange. Professionals use a variety of specially shaped scrapers and knives to access the bonding areas. The idea is to avoid damaging the fiberglass panels’ mounting flange.
If you can apply heat to the bonding adhesive, it does break loose more easily. But it makes more sense to break or cut the damaged panel near the bonding area first. Heat can then be applied to ease the removal of each panel. As you apply heat, a large, stiff scraper works nicely to separate the bond.
Once the complete panel to be replaced is out of the way, flange clean- up begins. The idea is to remove just the old bonding adhesive, then roughen the flange for the new adhesive. Remember the fiberglass goes away quickly when using a high-speed grinder.
Once all the flanges have been cleaned up, it is time to fit the panel. Most fiberglass manufacturers leave material at each end of the panel to allow proper fitting. They usually have notes on the panel that state “FIT PRIOR TO PAINTING.” That absolutely means you own the panel if it has paint on it.
Since I am installing a major fiberglass assembly, I need to consider what other body panels are affected. I should check the door gaps to door frame before installing the front end. My resto expert, Seth, likes to center the doors on the hinges first. Then he checks the fit of the door at the front where the front end meets the vertical door seam. The goal is to avoid doing any major reconstruction of the door gap at the front. Seth explained that, if necessary, he could build up the rear of the fender for a nice, tight, even door gap.
Always think about what other panels come into play before bonding any panels into place.
For the ’63, I need to check the fit before bonding: I had a really good looking 1966 convertible come into the shop in baskets, boxes, dollies, you name it. The bodywork was completed and the paint looked very nice. All I had to do was put it together. After being on the receiving end of so many of these “all you have to do is put it together” projects, you become highly skeptical of these jobs because they are never that simple.
The first tool I pulled out of the box was a tape measure. With the customer standing alongside me, I did a diagonal measurement of the frame. Sure enough, it was tweaked. The first order of business was having the frame straightened. But that was just the first of one problem after another.
Once the frame had been assembled, it was time for the body installation. At that time, I found some serious problems. Remember, I said the body had really nice paint. But when I began assembling the exterior, things went horribly wrong: None of the taillights fit properly in the rear surround. They weren’t off just a little; the rear surround needed extensive reconstructive surgery to get the lights to fit.
What I am trying to stress here is that you make sure everything fits before any primer is sprayed and absolutely before any top coats are applied. That project cost plenty extra to fix everything so that the car looked presentable.
The doors should be fit prior to hanging the front end on the cowl. The front end can be held in place with screws as each area is fitted. Once you feel that the front has been fitted properly, go back and check the door gaps. The old adage “measure twice, cut once” applies here. Fit everything carefully, then check everything again for fit. Once you glue the panel in place, you risk damaging it if you have to remove it for placement changes.
You should have everything ready and waiting for the adhesive installation process. The fasteners holding the front end in place should be removed, and the front end set aside. Have all the fasteners in an easy-to-access location with the proper installation tools. Now, the bonding adhesive is mixed for application on the flanges.
Be sure to read and understand the bonding adhesive manufacturer’s recommendations, especially on setup time. You have to apply the adhesive, then put the front end in place with the fasteners within a set time, dependent upon ambient temperature. Once the front end is set in place, your fasteners should be installed to align the assembly correctly.
Wipe off any excess bonding adhesive. General Motors did not do that, of course; they assembled plenty of cars daily, so the assembly line workers wasted very little time cleaning up. NCRS cars should not have the excess bonding adhesive wiped clean for authenticity. At this stage, it is a matter of waiting until the adhesive sets up, which often means letting things sit overnight.
Once all the major fiberglass issues have been taken care of, minor repairs should be handled. The details make a big impact on how well the finished project looks. During an earlier inspection, I noticed a few additional holes in the firewall from accessories that were added over the years. Screw holes in the fiberglass strip out easily and require repair to avoid having to use incorrect hardware. Look back at your notes from the disassembly phase and make the repairs before the paint is in place.
Final fit check is in order now. This is your last chance to make any adjustments or changes to component fit. Check the fit of each emblem in its respective position. Do they sit flat against the panel? Make sure the grille, rear taillights, etc., all fit properly. Check door gaps and hood fit. One final once-over can save you plenty of aggravation when it comes time to assemble.
Now, you’re at an exciting point in the restoration when it’s time to install all the exterior trim items, and you are able to see just how great the finished product looks. Or it can be a game changer with a “for sale” sign and multiple boxes of your pride and joy on the floor.
I dabbled a bit in metal work on the body and more is needed. The chassis requires some work, either simple scrubbing and light sanding, or major reconstruction. My project had a junk frame, as I explained earlier. I had a couple of options: I could get a fresh frame from a known good source, or hit the swap meets. I chose a professionally-built original frame from Impact Restorations to be sure I had a solid, straight frame. The swap meet option could work, but can be risky. Since this is the foundation of the entire project, why take a chance?
Many pieces are available to repair an original frame. Replacing a frame rail at home is not for everyone. Care must be taken in aligning and making sure the frame is square. First, you need to find a perfectly level spot to repair your frame. Next, a fixture should be constructed to ensure correct installation while welding.
By then, quite a bit of money and time will have been spent with possibly questionable results. The cure for a corroded or tweaked frame is replacement or professional repairs. Let the experts take care of this very important piece of the puzzle. Once the frame’s integrity is guaranteed, you can take over and do the prepping and painting.
Prepping to Paint
If your frame is indeed square, with minimal or no corrosion, or you are starting with a replacement, the next step is prepping it for paint. A thorough clean-up is in order, to avoid blowing debris from all the bodywork onto the fresh paint. Preferably, a complete wash down is the best way to eliminate the dust and dirt. Use a water-based solution from a body shop or paint supplier for the wash down.
Your paint supplier has a specific product that does the job without leaving any harmful residue.
By now, most original frames have been painted numerous times. This is actually a good thing though because bare frames corrode quickly. General Motors coated the frames with a mineral-spirits-based product that easily washed off. Engine oil, coolant, transmission fluid, and just about anything that dripped on the frame would remove the coating. This means that many frames are covered with rust if they have not been painted before. If by some chance the original factory coating is still on the chassis or the engine had massive oil leaks, rust or corrosion damage is minimal.
Before you select a method of metal preparation, you need to decide how your refinished components should look when completed. Bloomington Gold or NCRS chassis components must be carefully cleaned to avoid changing the base metals’ raw surfaces. The options for removing the old dirt, paint, and corrosion are varied. Professional blasters are the easiest to use. Using a mix of professional blasting with manual removal of the crusty covering on the parts may save a few dollars.
Grease and Oil Removal
The first step is chemically stripping off the years of grease and oil. The grease you find under any car is a mixture of dirt and oil, and therefore sandblasting the oily grease away does not work. Grease contaminates the blast media making a mess of the equipment and media.
Forcing the grease into the metal with the blaster is not a good thing either. A thorough washing with an aqueous degreaser is best. Mineral spirits works well, but must be disposed of properly.
Make sure you consider where you can dispose of any hazardous waste before you generate it. Gasoline should never be used for cleaning any component or part. One spark from a scraper or wire brush can ignite and possibly destroy your project and you along with it.
Once the pieces are degreased and dry, you can move onto the next step of restoring the part’s finish. If you decide on sandblasting, what grit works best? Professional sandblasters are typically in a hurry to finish, so they often use aggressive, large grit in high-powered blasting equipment. The large sandblasting grit leaves pits and removes subtle machining marks.
If you decide to go the pro blaster route, make sure they understand what you expect. Ask them to use lower air pressure and finer sandblasting grit. If the blaster agrees to customize his work, be prepared to pay extra labor costs. Sandblasting is tough, hot, sweaty work, especially on a summer day. It cost me $650 the last time I had a chassis and all the attaching pieces blasted. While this may seem like a lot to pay for cleaning pieces, I would have spent 40 to 50 hours or more cleaning, so it was definitely worth it. Also keep in mind that the cost of wire brushes, sandpaper, and blasting grit can be expensive.
Using a bead blast cabinet is an alter-native pressurized cleaning method. Bead blasting grit is much finer and prevents surface damage, but it does take longer. Of course, a number of pieces don’t fit in the standard bead blast cabinet.
Large, efficient bead blast cabinets save plenty of time, but are expensive. Plus, large cabinets take up a lot of valuable shop space. Smaller, less expensive bead blast cabinets are typically suctionfed blasters, which are not very efficient. The suction fed blasters can be painfully slow as they remove grime and corrosion. Small chassis pieces are more realistically blasted in small hobby-type bead blast cabinets.
Motorized wire brushing is an alternative that works fairly well. Wire brushes on bench grinders can remove years of crud quickly and easily. Bench grinder wire brushing does have draw-backs though, as it’s often difficult to get into tight cracks and crevices.
Wire cup brushes spun in an electric drill are more versatile, making it easier to clean in tight spots. But these require care when operating because you can get hurt. Spinning brushes lose their metal bristles at high speed and they are flung at you. Slipping while using any highspeed tool can take off a large patch of flesh immediately.
Another serious concern is losing an object in the wire brush. The object could be thrown back at you, causing bodily harm. Be sure to wear eye protection and leather gloves when using any high-speed cleaning equipment.
A mix of wire brushing and bead blasting can save you time and quite a bit of money. Use the wire brush cleaning process as much as possible before blasting. Once you have the majority of the build-up removed with the wire brushing, blasting gets into the tight spots.
After the raw oil-free pieces are finished with the cleaning process, a time sensitive situation begins. Washing the pieces with soapy water is required to flush out the loose particles and blasting media. Blow drying the pieces with dry, oil-free compressed air as soon as pos-sible after washing limits inevitable corrosion. Touching the pieces with sweaty hands also starts the corrosion process. It is important to keep oily, sweaty hands and arms off the clean pieces. The use of nitrile or latex gloves while handling the pieces is recommended. The reason for all the cleaning and preparation is to promote good paint adhesion. The labor-intensive preparation process is necessary to ensure long paint life. Before primer is applied, I go one step further and apply a preparation solution to the raw iron metal surfaces.
Ospho metal conditioner is a rustinhibiting coating that preps the raw metal for painting and can take a few hours to dry completely on hot, dry days, or 24 hours on cool, humid days. Light applications work best to avoid rough spots where the inhibitor has pooled.
New metal or raw blasted metal turns gray as the Ospho transforms the metal surface. If you prefer to skip the complete removal of the rust, Ospho treats the pieces for primer. The scaly rust particles become black as the treatment turns them into iron oxide. Do not use this product on any aluminum or pot-metal pieces.
By now, you may be wondering if all of the cleaning will ever end. Typi-cally, the chassis requires the most labor and time to clean because it is assaulted not only by engine oils, transmission fluid, and differential grease, but also by whatever the road throws at it, whether it is water, salt, or cavernous potholes. Don’t forget the time that it spent on automotive repair lifts or worse yet: floor jacks.
Many, if not all, the frames under Midyears have caved-in front crossmembers. A repair tool is available if the cross-member is not too banged up. The tool fits inside the crossmember and a fixture is placed on the outside to pull the dents out. One front spring must be removed to insert the tool inside the frame. The best time to repair the crossmember is while the frame is in pieces.
The 1963 project walk-through should put the bodywork and chassis prep requirements into perspective. This is not the worst-case body reconstruction. Many times windshield frames are severely rotted and require major panel removal to make repairs. I have even seen windshield and door pillar rot that required complete front-end removal. In some cases, the roof fiberglass required removal to access the bad pieces. The better the body is, the less you need to know about structure or worry about completely rebuilding your Corvette’s body.
Step-1: Grind Fiberglass for Repair
A 3-inch-diameter disc is used first to remove the majority of material at the center of the seam. You want the edges of each panel to be thin and then tapered upward. The aggres-sive 36-grit disc is mounted on a flexible backer to allow the disc to follow the panel’s curvature. The paint suit and shop vacuum help keep some of the irritating fiberglass off during this messy part of the task.
An 80-grit disc on a larger-diameter air grinder roughens up the area surrounding the seam. The taper is pro- nounced a bit more outward, hopefully without grinding through surfaces. Coarse-grit grinding discs ensure that the resin has good bite during the fiberglass work. Be cautious, though, because the aggressive-grit discs chew up material quickly.
Step-2: Cut Fiberglass Mat
You must cut your fiberglass mat before you even think about mixing any resin. There are two sheets of mat thinner than the final top sheet to taper the repair. The fiberglass mat goes over the crown of the fender because the panel repair seam goes into the factory side-fender seam.
Step-3: Apply Resin and Mat to Repair Area
An ample coating of resin is applied beyond the area of fiberglass mat. Do not try to save resin here. A healthy dose of resin is required because it soaks in quickly. Make a couple of passes over the area, filling the brush each time.
Step-4: Lay Mat on Repair Area
Timing is important when the first layer of fiberglass mat is soaked with resin. Apply resin to the mat until it is saturated. Then lay it onto the seam, splitting it down the middle.
Step-5: Fine-Tune Application Technique
Use an inexpensive, throwaway application brush to push down the fiberglass mat and soak any dry areas. You want the entire area to be wet with resin for the next application of mat.
Step-6: Squeeze Out Air Bubbles
Between each application of fiberglass mat use a job-specific roller to force out any air bubbles. This should be done over the entire mat area with wet resin. Forcing out the air bubbles is very important to prevent delami- nation of the subsequent layers of mat.
Step-7: Avoid Air Pockets
An air pocket is underneath the fiberglass matting that was placed over the top edge of the fender. When the matting changes directions it has a tendency to develop air pockets. This can be seen as the light- colored circular area in the center of the vertical area. The light- colored area is more prominent on the left side of the splice seam.
Step-8: Saturate Repair Area with Resin
The best policy is to saturate the vertical area with another application of resin to remove the air pocket. An air pocket is disastrous to the integrity of the body panel, especially if it lays down just enough that the sander does not break into it. Days, months, or even years later a major bubble may be noticeable when it finally comes loose from the resin.
Step-9: Apply Final Coat of Resin and Mat
The final, wide layer of resin-soaked fiberglass mat is laid down. Note the wide fiber- glass mat is going into the rear window glass area to prevent a ragged edge on the corner of the body where the stainless-steel trim sits against it. Keep in mind that this entire three-layer procedure has been accomplished within a 20-minute window. Each layer should go on top of wet resin for best results.
Step-10: Work in Resin with Roller
Starting at the center and working outward, make one more pass with the roller over the entire area to force any remaining bubbles out. The edges need to be rolled well to prevent them from curling upward.
Step-11: Properly Position Mat
You must force the fiberglass mat into the corner while applying resin to make sure it sticks well. Carefully watch this area for a few minutes. Make sure it does not come up and away from the window channel as it cures.
Step-12: Apply Heat to Repair Area
You should wait approximately two hours for the repair to cure before shaping the area. Apply heat to the entire area to confirm the integrity of the repair and verify that that the repair has not been compromised. To speed up the curing process, professionals use infrared heat lamps to cook the repaired area and check for lamination defects. You can buy a home infrared lamp or find a deal on a pro model. An alternative to the heat lamp is to let the Midyear sit outside for a week on sunny days to see if any surprises occur. Better to know before the top coat is on for sure.
Step-13: Shape Rough Repair Area
The raw fiberglass repair is rough sanded to get it close to its correct contours. Repaired areas should be shaped before a coat of filler is applied to keep the consistency of the body filler uniform. Additionally, when the filler is applied, the 36-grit paper gives the surface bite. Smooth surfaces allow the next application to peel off easily or, worse yet, bubbles to form and show up later. Note the respirator. Our body worker not use his paint suit to avoid the fiberglass dust. Some people can tolerate the fiberglass dust and minute pieces of glass and others cannot. If you do happen to get these painful flecks on you, cold water works best to rinse them off. Hot water opens the pores and draws in the itchy fibers.
Step-14: Clean Repair Area
The area is roughed in and looks almost ready for primer. Blowing away any stray fiberglass debris ensures a good bond for the next coat. Blow out any pin holes with extra caution. If they are not cleared of all debris, tiny bubbles may show later.
Step-15: Apply Adhesive Filler
Apply Evercoat Vette Panel Adhesive/Filler to seal the fiber- glass strands and add strength to the area. During mixing, milled fibers are dispursed throughout the panel’s adhesive/filler to add reinforcement. The idea is to achieve the final contour with just one coat. This milled fiber reinforced filler is difficult to sand and requires extra work to smooth out. Carefully applying the filler can save you plenty of elbow grease.
Step-16: Sand and Shape Repair Area
Use 80-grit sandpaper with the block sander and take long deliberate strokes to shape and smooth the area. Remember to avoid pushing down too hard as you sand. The repair area flexes and can cause unexplained low spots. In this area, a long sanding block works best to keep the surfaces flat. Do not be disappointed if it takes multiple applications to get the panel contour correct.
Use a piece of round steel tubing with 80-grit sandpaper to smooth out the inner contour at the rear deck. Like the sanding block, this tubing keeps the sanded area spread out to prevent low spots and dips.
Left Fender Repair
Step-1: Inspect Body
This damage appeared to be minor until all the grime and under- coating was removed from the wheelhouse. Most likely, this damage was left behind from the rear partial upper surround repair work. The area was cleaned, ground out, and prepared for fiberglass mat installation. The trick is having the fiberglass mat follow the original contour.
Step-2: Position Fiberglass Backing Material
I backed up the missing piece of the wheel house and body support from inside the passenger compartment. A piece of cardboard was conformed to mimic the original fiberglass panel. Mold-release wax was applied to the cardboard back-up mold then fiberglass mat and resin were applied to the area. Good to see that the major structural corner has been repaired correctly, not just covered up as I found it.
Step-3: Fabricate Replacement Body Pieces
The extent of the birdcage damage is shown at the driver-side door latch area. The replacement piece must be fabricated from a sheet of steel. The area will be cleaned up and rust inhibitor applied before the newly fabricated piece is installed.
Fabricating replacement pieces for the birdcage is commonplace, so some metal work is involved even on fiberglass-bodied cars. The piece is welded in place then coated with primer to prevent the same occurrence. Once the fabricated metal piece has been welded into place the original fiberglass sill cover can be installed.
Step-1: Prep Bonding Area
Use 36-grit grinding discs to remove any residual bonding adhesive. The aggressive grinding discs roughen up the flange to create a good surface for bonding adhesive bite. All the flanges should be cleaned of old bonding adhesive before fitting the front end. Clean any panel that is to be replaced before fitting.
Use a 36-grit grinding disc to rough up the edges of the front end or panel to be glued. This is very important for proper adhesion of the panel. Once the grinding has been completed, blow off any remaining dust and debris.
Step-2: Apply Bonding Adhesive
The bonding adhesive is ready for mixing. Be ready to quickly apply it because you have 20 minutes to spread the adhesive and have the panel or front end in place. Once the adhesive begins to set-up, you cannot get the panel to stick.
Apply panel adhesive to the flanges using about a 1/2-inch-thick bead, and now the process must continue. Apply adhesive to all of the upper flanges leaving the vertical portions for the next application because there is not enough time to apply adhesive to all the joints at one time. Don’t try to do too much at once. Better to be safe or you may have to take the entire front end off and try again.
Step-3: Position Fenders
Now the front end with the inner fenders installed can be set in place. The side fenders need to be pulled outward to go around the cowl at the doors. You need to plan out the procedures before the adhesive is mixed. The front end must be placed back in the same position it was fitted in as soon as possible.
Step-4: Set Clamps and Tighten
Place clamps every foot or so to make sure the adhesive is pushed level at all of the attachment points. Be careful with the clamps and do not apply too much pres- sure. It needs to firmly hold the panel in place, but you don’t want to crush the panel. There- fore, do not overtighten the clamps. If you hear cracking, loosen the clamp immediately.
Step-5: Set Proper Spacing Between Front End and Cowl Flange
Force a screwdriver between the front end and the cowl flange. This allows for enough of an opening for the bond- ing adhesive to be squeezed in.
Step-6: Install Screws in Fenders
Now the screws used for alignment are put back into place in the side fenders until the bonding adhesive dries. Within an hour, the bonding adhesive should be cured if it was mixed correctly. If not, the panels pop off easily with a slight tug. Then you have to start back from the beginning grinding the flanges for a fresh start.
Step-1: Apply Metal Surface Prep
Apply Ospho metal surface prep with a sprayer then wipe it off. Try to avoid pooling of the material because it causes crusty formations on the pieces. Unfortunately, leaving the crusty particles makes them very notice- able after painting. Ospho contains phosphoric acid so make sure you use gloves and eye protection and avoid getting it on your body or clothes.
Step-2: Remove Dents
This nifty tool kit from Corvette Central straightens the front cross- member. The upper fixture tightens down to push out the bumps and waves. Heat can be applied to the crossmember as the fixture is tightened. The crossmember should be cleaned internally of any grease or oil before applying heat. For the most part the front cross- member dent removal tool worked well. I applied a skim coat of all-metal body filler to slick it out completely. This is the perfect use for the extra tough all-metal filler. I used all-metal filler in a number of places on the chassis to smooth it before priming.
Step-3: Clean Up Frame
One of my pet peeves is all the slag and debris left behind from the factory welding process. I use a cold chisel to knock off the welding beads on the entire frame. No, it is not NCRS correct, but it sure looks better. Another plus is less of a chance for bodily harm if your hands accidently brush against the frame while working on or near it.
Written by Chris Petris and Posted with Permission of CarTechBooks