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1970 Plymouth Barracuda Grill Repair - Gettin' GrilledPlastic Repair Is Sometimes A Necessity From the November, 2000 issue of Mopar Muscle By Steve Dulcich
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With new aftermarket repops, a large part of the semi-serious resto game is handled fairly painlessly. On the other hand, new NOS and premium used stuff can only get thinner every year. While there's still a steady stream of salvaged used items on the market, the rarest and most desirable items, especially those that are not being reproduced, are commanding ever higher prices-if you can find a cherry piece at all. Take a 'Cuda grille for instance. This complex chunk of molded plastic isn't being reproduced, and likely never will. Need one? Would you pay $250 for a battered center grille, sans all the trim? How about $800 for a reasonably clean complete used piece? Want the best? Close to $2000 for a mint NOS three piece set with new trim in the original boxes. We all want the best for our cars, but the reality of affording that luxury is often another matter. To fix it right, the grille... To fix it right, the grille has to come out. First to go are the headlamp bezels, which are attached with four screws. The nose of my own '70 'Cuda was looking pretty shabby. Back in 1988, the missing original grille was replaced with a sweet junkyard find from a '70 Gran Coupe. Looking back at the cost of $45, it's laughable today. Now, all would have been well if I hadn't loaned the car to a well-intentioned brother-in-law while I took an extended job overseas. When the abandoned car was recovered from his ex-girlfriend's garage years later, the nose was smashed, windshield cracked, convertible top slashed, and engine fried. The slashed top, cracked screen and cooked mill were really no problem; but that grille..damn. The center grille is mounted... The center grille is mounted with machine screws which thread through plastic bushings in the metal support, and into clips mounted on the grille. If the plastic bushings are removed in a resto, they will almost always break. The 'Cuda temporarily landed in the hands of a friend who got the abused Mopar running and sent it in to a local body shop for repairs to the damaged nose. The body shop in question slapped some bondo over the cracked grille, hosed it with some Krylon spray-can silver, and called it good enough. Needless to say, things were ugly up front, but what to do? The days of the dream finds are basically long gone; there would be no $45 mint 'Cuda grilles for the picking. Weighed against the costs of finding a suitable replacement, the path was clear-fix it. Right off, let's be clear: Taking a busted-up piece of anything, be it a fender, door, or grille, and making it presentable isn't easy. Making it look as nice as new is even tougher. Use the wrong materials and techniques, and it's impossible. Personally, I don't fix grilles every day, but I've done my own body and paint for over twenty years. Attempting these kinds of repairs takes skill and, more importantly, patience, neither of which we can provide in this story. What we can do is pass on the methods and materials that we've found successful over the years. Add in your own skill and time, and the results can be outstanding. The repairs to this grille required twenty hours of working time, start to sweet finish, of which only a sampling is covered here. Sure, it takes a while, but the finished product is nothing short of as-new beautiful.  R/T Specialties has the hard...  R/T Specialties has the hard to find bushings/screws/clips in a kit-get it. The front bumper usually has to come off for the center grille to clear it on its way out.  The shop that last fixed this...  The shop that last fixed this grille figured that spray bomb silver was a good match to the factory Argent finish-it isn't. The gluggy paint was stripped by sandblasting. If you have to strip the grille, use extra-fine sand, a large nozzle on a suction feed blaster, and some distance between the gun and the plastic. The sand will strip the surface and bounce off the plastic. The resultant texture is fine for a rough Argent finish, and perfect for repair adhesion. Work slow, and don't use too much pressure or you'll kill the grille.  First the basics: a crack....  First the basics: a crack. The crack in this bezel was non-structural, since it didn't go clear over to an edge.  First the crack is "V-ed"...  First the crack is "V-ed" out to about 2/3-3/4 of the way through the thickness of the plastic. We used the same carbide cutter used to port heads, mounted in an air die grinder. The "V" increases the surface area for the repair material to adhere to, making for a much stronger repair.  Plastic in a tube; SEM Weld...  Plastic in a tube; SEM Weld Ridged Repair Material is a professional product used for repairing plastic parts and can be purchased at body shop supply houses which carry the SEM line.  Mix equal parts of the repair...  Mix equal parts of the repair material and resin. The SEM Weld is troweled into the groove, both filling and bonding the flaw. Working time until it begins to cure is very short, so mix only a little, and then slap it on. A small piece cut from a larger plastic bondo squeegee is the tool to use.  The SEM weld can be sanded...  The SEM weld can be sanded like Bondo, but it takes more effort. Make sure to over-fill the repair slightly, so that it can be sanded down flush; #80 grit paper cuts it well. If the edges peel, the SEM Weld hasn't had enough cure time or the repair area isn't clean or roughened adequately.  The repair profile should...  The repair profile should be made nearly perfect with the SEM Weld; if it isn't, apply another layer of the compound until it's right.  The SEM Weld feather edges...  The SEM Weld feather edges fairly well, but not fine enough for a invisible repair. We used fine polyester finishing glaze, a body repair product, for the final surface finish. It mixes like Bondo (which it basically is, only finer) and is spread in a very thin layer. Extend the glaze past the area previously sanded. The glaze fills any pinholes, gives an invisible feather edge, and fills the relatively rough #80 grit sanding scratches from the previous step.The glaze should only be used as a surface finish, since it isn't structural like the repair compound. #220 grit sandpaper works well to cut back the glaze, with a final sanding using #320. After sanding, it should be so thin you can see through it.  With a light dusting of primer...  With a light dusting of primer sealer, the repair is invisible. The back side of this bezel, as with all the repairs on this grille, was also filled (don't "V" groove both sides) and finished for a perfect fix.  On our center grille we had...  On our center grille we had this break which is structural because it goes all the way through and ties the upper to the face portion of the grille.  Though the SEM Weld is good,...  Though the SEM Weld is good, in highly stressed areas no glue will hold over the long term like the original plastic. The solution is to add a metal splint, which we cut from .010-inch-thick sheetmetal. After the break area and splint are roughened, the splint is bonded across the back of the break with the SEM Weld.  Once cured, the edges of the...  Once cured, the edges of the bonded-in splint are sanded flush, and the metal is fully encapsulated in another application of the SEM Weld.  Once sanded, finished glazed,...  Once sanded, finished glazed, and resanded, the repair is undetectable, and extremely strong due to the steel splint.  The face side of this break...  The face side of this break was fixed like the bezel: grooved, bonded, glazed, gone.  One of the ugliest parts of...  One of the ugliest parts of this grille was the center nose, which was cracked, busted, and improperly body shop repaired. First the Bondo was picked out of the broken area. Adhesion was poor, and the Argent paint underneath showed that the filler was just slapped on. Note that two of the trim mounting lugs are also busted off (Arrows).  Cleaned and "V" grooved, the...  Cleaned and "V" grooved, the area was ready to repair. Note the substantial hole.  First the forward crack was...  First the forward crack was given a metal splint reinforcement, since this is one of the most highly stressed areas of the grille. Without reinforcement, it would eventually crack again. Also note that the grille mounting tab at the center was completely broken off (Arrow); we'll fix that later.  To back up the hole for filling,...  To back up the hole for filling, tape it over from the backside. Otherwise, the filler will just drop out.  On the front, the SEM Weld...  On the front, the SEM Weld was applied as in the previous repairs, making a solid fix.  Getting the shape right up...  Getting the shape right up front requires finesse. Make sure to work the repair to near perfection with the SEM Weld rather than trying to cheat with the easier-working glaze or bondo-it won't hold.  The glaze again is paper thin,...  The glaze again is paper thin, just to fill surface imperfections and provide an invisible feather edge.  All fixed, the nose of this...  All fixed, the nose of this grille looks factory perfect. Notice that the grille sprouted the two missing trim lugs in this photo-more on how those got there later.  By far the toughest part of...  By far the toughest part of fixing this grille was the two missing fins in the upper left lattice. Since the broken-out bits were long gone, new ones would have to be made. First the broken area is ground square, and "V-ed" back. Don't "V" the edges of the remaining grillework right off their support!  We used Lexan sheet (in the...  We used Lexan sheet (in the proper thickness) for the stock material to make the broken fins. It's easy to get, heat workable, and won't propagate a crack like Plexiglas. The fins have a bend in the middle, which we replicated by bending the Lexan in a crude brake made from steel bar and angle iron, using an oxy-acetelene torch for heat. It was tricky. A good glass or sign shop could probably do the bend with ease.  Skill or luck, it worked;...  Skill or luck, it worked; the angle of the bend matched the stock fins perfectly.  The Lexan can be hacksawed...  The Lexan can be hacksawed or ground to shape. First the surface was thoroughly sanded until opaque. Then we marked the center of the bend and measured the required length forward and back, marked it, and then ground to the mark on a bench grinder. The final edge was cleaned up with a file.  After matching the required...  After matching the required length and "V-ing" the bottom, the replacement fin was bonded in.  Here the next fin is bonded...  Here the next fin is bonded in. The fin above it (Arrow) has been sanded, glazed, and finish sanded.  With the primer coat on, the...  With the primer coat on, the damaged area now appears perfect.  Now to fix the broken mounting...  Now to fix the broken mounting tab from photo 15. First the remains of the tab are ground flush.  A cardboard template was made...  A cardboard template was made by copying one of the remaining legs of the tab, and then the template was transferred to sheet metal, the tab folded using a vice, vice grips, and some hammerwork, and then it was bonded in. Notice that the replacement tab has a wide flanged foot all around, giving the surface area a strong bond.  As for the missing two small...  As for the missing two small trim lugs in the center of the grille which we sprouted in photo 22, they were carved out of billet aluminum with a hacksaw and some files. The grille was roughed, and then the replacement lugs bonded on with the SEM Weld.  Speaking of trim, the delicate...  Speaking of trim, the delicate stainless grille surround trim on this 'Cuda had no less than 17 dings. These were all bumped until perfect, using a variety of hand shaped tools, and then sanded smooth.  The trim was then polished...  The trim was then polished using stainless compound on a Dixco buff wheel turning at high speed in a drillpress.  The hard work done, now the...  The hard work done, now the glory and glam-paint. Forget the hardware store spray bombs; the only way to a lasting finish is real paint through a gun. We used PPG acrylic enamel. Although this is probably the opposite of the factory sequence, the center black was shot first. Mix the black with flattening base to get the required semi-gloss. Notice no masking is used at this point.  Next the black was masked,...  Next the black was masked, and the PPG Jobber-mixed Argent acrylic enamel was sprayed on. To achieve the high texture of the factory Argent, use a much faster evaporating reducer than what the ambient temperature would call for, in twice the label recommended proportion (we reduce 50/50). Use a slightly higher than normal air pressure, and hold the gun slightly farther away than usual. Fog the paint in using multiple light dry coats.  We again tapped R/T Specialties...  We again tapped R/T Specialties for the jewelry to finish our project, in the form of these Ben Snobar-manufactured reproduction 'Cuda grille bars. The original emblem was refinished, and we laid out the nice reproduction grille installation hardware kit from R/T Specialties.  Fixed, finished, and trimmed-out...  Fixed, finished, and trimmed-out to perfection, black and white photography can't do justice to the final product.
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