As in most other endeavors, in autobody metal work there are many special projects and procedures that are needed to move work along, and/or to complete it. Some of these are huge and daunting tasks like fabricating a complex assembly. Others are jobs that must be done repeatedly and routinely, like hanging and aligning doors or decklids. This chapter details some of these projects and procedures, starting with a very difficult and impressive example of this kind of work.
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At first, as I watched Matt, a metal crafter at L’Cars in Cameron, Wisconsin, fabricate a reproduction splash shield for a vintage Ford military amphibian vehicle, I was amazed that what he was doing could be done at all. Parts of the job, like patterning and cutting, were straightforward and familiar to me, but other parts of it stretched my concept of what is possible to accomplish when custom forming sheetmetal, without using stamping dies.
As I continued to watch Matt work on this project, two more forms of amazement joined my first sense of awe. I found it incredible that he could progress as quickly and certainly as he did, and I found the quality and precision of his results quite beyond anything that I had expected to see, or even thought possible. At times, his dexterity with the metal was so great that I had to remind myself that he was working with 21-gauge mild-steel sheet stock, and not a sheet of some kind of malleable plastic. The metal seemed to willingly respond to his every action.
This paper pattern has almost magical 3-D capabilities. Here it works flat, to outline the shape of the new splash shield. Later in this project, the cuts in it will allow it to indicate specific areas of the new part’s shape, in three dimensions.
At this point, it was not necessary to cut out the metal from which to make the new splash shield very accurately. The part would be trimmed to exact dimensions, later. Still, Matt made his cuts accurately because that is the standard to which he works.
These Steck forming dies, mounted in a Pullmax, form very quickly. The dies’ back areas impress V-shaped grooves into the work piece. Then, as it is drawn forward, through them, the dies’ crowned front surfaces flatten and upset the V-shaped grooves, shrinking, and forming the metal.
The Steck die operation left the metal pretty uneven, but with shrink areas in the right places. Next, a large English wheel was used to smooth out the metal. Note the area below the forming wheels that was made uneven by the Steck process.
These Eckold shrinking heads were used to produce very compact, local shrinks, and to smooth the metal. They work by mechanically gathering the metal between them in a controlled upsetting pattern. The result is the ability to create very specific local shrink areas.
Matt began the job by selecting material similar to that in the original splash shield that he was copying. He created an elaborate paper pattern of the original shield by out-lining it on paper, and then cutting reliefs, sideways into the paper, so that when it was deformed to close them, the paper took on the shape of the original, amounting to a three-dimension-capable template. This was not done so much for checking his final result with the splash shield, as it was to make it possible to check specific sections of it as he went along. Of course, he always had the original shield that he was copying to check his finished result against. The paper template served when he had questions about a particular bend or contour, as he was forming the new piece from rough. Essentially, it was used to guide his progress.
The early stages of this job required plenty of human intervention between machine operations. As the piece evolved, Matt used the Steck, Eckold, and English wheel devices to make his bends permanent. He did this by relaxing the metal into the shapes that he wanted it to take.
At times, Matt stopped to compare his work piece to the original splash shield. You can see that at this point, he still had a long way to go. He had created the basic contour of the piece, and the beginnings of some of its crowns.
As work progressed, the piece’s crowns began to appear. Matt used the English wheel to smooth areas disrupted by the Steck heads. Note one of these areas under and to the right edge of his left hand.
This paper pattern is being used to indicate one of the work piece’s corner crowns. As the grooves in the paper are closed, it bends into three dimensions, indicating other angles of the crown that are supposed to be in the metal under it.
A rough outline of the fabricated item was marked on the metal, leaving plenty of extra border material for later trimming and wire edging operations. The outline was cut out of the stock metal with an electric hand shear, along its straights and looser curves. Aircraft snips were used in its tight radius areas, its ends. All of this was pretty routine. Then the fun began.
The shape of the splash shield had been indicated roughly on the metal, with marked vertical lines at some of the cuts in the paper template. Different distances from each line to the next, and the lengths and angles of the lines, indicated curvature in the panel crosswise and, at its corner bend radii, lengthwise. Starting with the corner bends, which had curves in both directions (amounting to crown), these areas were worked into the metal with Steck forming tools, mounted in a Pullmax device.
As the Pullmax cycled closing, separating, and closing again the Steck shaping dies on the metal, the Steck dies’ front area impressed considerable V-shaped bends into the metal bends that stopped short of stretching it. Then, as Matt pulled the metal back through the Steck dies, their slightly crowned front area flattened the bends that had been V-bent by their rear area, creating an upset in the metal, and shrinking it. This also shaped it. It took a combination of skill, judgment, and experience to use this device effectively, but armed with these attributes, it is incredible what Matt accomplished, in a relatively short time, with the Pullmax and Steck dies. It was equally amazing that there was almost no collateral damage surface abrading, tearing, stretching, or cracking to the metal that he was forming.
The paper template indicated excessive crown in the marked area on the panel. Adjustment to the required crown in this area was too small for the Steck dies, while the crown radius was too tight for the Eckold heads. Another solution to shrinking and forming it had to be found.
The solution to upsetting and shrinking the mild inboard excess of crown was to push the metal through this cycle press, with a domed, steel-bottom die and a hard-rubber, flat, upper-die receiver (a hockey puck). This action put small, domed impressions in the metal.
The domed impressions were then hammered flat from both sides, and wheeled flatter in an English wheel. The result was to slightly upset the metal, causing local shrinks. This left it smooth, and in the correct crown.
A comparison of the Pullmax/Steck combination to a less advanced method of rough shaping metal, like the good old plastic mallet and shot bag routine, might go like this. It would be like the comparison of a sport utility vehicle to an F1 racing car they are both vehicles designed for transportation, but one of them gets you there much faster if you know how to drive it.
The Pullmax/Steck combination moves metal incredibly quickly but, understandably, it does not leave a smooth surface. To smooth his work and, to a lesser degree, to provide additional forming, Matt used an English wheel to work the area that he had shrunk and formed with the Steck dies. He employed a diagonal approach, from two directions, to smooth away the roughness created by the Steck dies.
The above-described operations were repeated several times, until the basic shape of the finished splash shield was pretty well established in the new metal, including the crowns that were inherent in its shape. As work progressed, Matt added the use of Eckold shrinking heads to his tooling routine. The Eckold heads were mounted in a press that cycled them toward and away from each other, pressing against the metal inserted between them. The Eckold device firmly grips sheetmetal, and then compresses it laterally. Think of this as a mechanical gathering action. The surfaces of each head’s halves grip the metal as they compress it, and then move toward each other a small distance. This creates a small, compact upset a defined and local shrink. The operator can control the amount of the shrink in several ways, in particular by adjusting head pressure the distance between the heads in their repeated strokes and how many cycles he or she allows the metal to be compacted in a given area.
Behold the rare and lovely Magee Wire Edger. It uniformly wraps sheetmetal edges around wire cores. It can handle mild curves in three dimensions. That amazing feat qualifies it for my list of the Seven Sheetmetal Wonders of the World
The next step in fabricating the splash shield was to roll the first of three lengthwise beads into it. A tape line was pulled in the position of the first bead, and marked on the metal. The bead was rolled slowly and accurately with a hand-operated bead roller.
Do not think that all of this sophisticated tool work was occurring untouched by human hands. As Matt alternated use of the Pullmax/Steck operation with wheeling on the English Wheel, and Eckold head shrinking, he also did some good, old-fashioned hand bending, to make the piece go into the correct curvatures. Once he had the right contour in his work piece, he used the machines to refine it and to make it permanent. Because Matt’s shaping approach involved sequential force and stress relieving operations, the panel acquired impressively little stress and hardness as he worked it. He also avoided producing any thin spots.
I have seen metal worked with conventional hand tools in dimensionally smaller amounts than this, and become so brittle and stressed that it cannot function as it is supposed to, without springing out of shape, or even cracking. By comparison, the metal in Matt’s panel remained supple and resilient throughout the process.
Of course, Matt checked his evolving fabrication often against the original piece, as his work progressed. As the crowns and curves in the new piece became more and more regular and authentic, its surface became smoother. It began to look finished.
No matter how good the piece looked, however, it was critical to its dimensional correctness to keep checking it against the paper template. Those comparisons provided better and more useful indications than could be derived from comparisons to the original splash shield. To verify specific areas of the new piece, checking against the paper template informed exactly where the new fabrication might be off, because it was possible to position the paper template exactly over any particular area in the work piece. At one point, the paper template indicated excessive bulge in the crown at the new shield’s corner bends.
To correct this, Matt performed some radical cold shrinks and reshapings where the metal was bulged. This was done with a cycling press that impressed the metal between a domed steel tool, and a hard rubber surface, basically a hockey puck. The result was then upset with a body hammer over a shot bag, and smoothed out on an English wheel. This corrected the last major dimensional deviation in the basic shape of the fabricated part. More work with the Eckold heads and English wheel fine-tuned minor areas of the piece, until it very closely approximated the original item when compared to the paper template.
The original splash shield had most of the length of its edges wrapped around a wire core, the exception being the attachment areas at its ends. To duplicate this configuration, Matt used a Magee Wire Edger. This was a common production tool, from Model T days into the 1940s. Somehow, Bob Lorkowski, the amiable proprietor of L’Cars, has resurrected one of these extremely rare machines for use in his shop’s restoration work. A sheetmetal edge, not necessarily a straight edge, is fed into the machine along with a piece of core wire. The Magee bends the edge of the sheetmetal uniformly around the core wire, with absolutely no fuss or visible distortion. It is an amazing process to behold.
With the first wire edge installed, and the first bead rolled into the metal, it took on a new firmness. Matt now did some manual shaping. Note the contour outline marked on the floor for checking the piece’s shape. The first rolled bead is clearly visible.
The second and third beads were now rolled into the splash shield. A little re-rolling touchup in a tightly curved and crowned section of the third bead is shown here.
At this point, the Eckold heads were used to shrink and smooth a small buckle in the edge of the metal. This was in preparation for installing the second wire edge in the work piece.
The second wire edge was rolled into the metal, using the miraculous Magee Wire Edger. While this machine makes this look simple, it takes skill, judgment, and experience to achieve good results with it. The hardest part of using the Magee is setting it up correctly for a job.
With the second wire edge completed, the piece was in its final form. It remained only to refine some of its details. Here, Matt is fine tuning one of the beads. Later, he uses a body hammer and a die that he had fabricated to make the beads’ ends uniform.
The Magee Wire Edger couldn’t follow the sharp bends. After shaping and welding in wire, Matt bent the edge of the metal over the wire with locking pliers. He had to anneal the metal once to finish this bending job.
With the first of the two wire edges on the work piece formed, Matt and some helpers used a bead roller to roll the bead nearest to the wire-cored edge into the work piece. This required the use of a deep-throat bead roller with a manual drive. The bead was rolled slowly enough to precisely follow a tape line that Matt had marked on the metal for guidance.
The rolled wire edge gave the piece strength, and the first rolled bead added to that strength. Now, Matt manually bent the piece into final shape. Up to this point, it still had been too floppy to hold its final shape. Now it did.
The other two beads were rolled into the piece, with dimensional checks and small corrections made to it along the way. The Eckold shrinking dies were particularly useful at this point for stabilizing the metal in its correct and final shape.
Matt fabricated these shield mounting brackets from flat stock, and spot welded them onto the splash shield. Talk about detail! Even the brackets that he fabricated were faithful replicas of the originals.
With the third bead rolled into place, and the metal checked and rechecked for fidelity to the original piece, the second wire edge was added. At this point, the piece became quite strong, while showing no tendency to want to spring or oil can into and out of shape. The metal contained little stress. Metaphorically, it seemed happy and at peace with itself. Maybe you just had to be there to sense this.
The second wire edge was added to the new splash shield, and minor corrections were made to the rolled beads, and to the metal around them. The ends of the beads were made uniform with a hammer and a special die that Matt had fabricated for this purpose.
Finishing details and features were added to the new splash shield. Two three-dimensional strap holes were formed near its bottom edge. Wire edging was completed around an indent in its top edge, which contained turns that were too sharp for the Magee Wire Edger to follow. This was done manually, by welding in a shaped piece of wire that followed the contour of the indent, and rolling the splash shield metal around it. Annealing heat was used to soften the metal in this area to allow completion of its severe deformation around the wire. Top brackets were fabricated to duplicate the originals, and then spot welded into place. Finally, mounting and rein-forcing plates for the splash shield’s ends were formed to duplicate the originals, and spot welded to the splash shield.
The authenticity of Matt’s fabricated duplicate piece was superb. This was one of the most difficult metal forming jobs in steel material that I have ever witnessed, and it was done with an exactness of shape and detail that is at the far limit of what can be accomplished in fabricating sheet-metal. Note that when the finished fabrication is put into service, it will be visible from both sides. It will be subjected to severe service, in terms of impact, vibration, exposure to weather, and possibly to corrosive sea water. Surviving these factors made it impossible to take the easier route of fabricating it from welded-together sub-sections.
It also is impressive that the whole process of making this piece took less than a day and a half, and that included considerable time that was spent answering my questions, and stopping work so that I could photograph it.
Making Panels and Trim Fit
From replacing quarter panels to making grille or headlight trim surround pieces fit properly, autobody panel work constantly requires adjustments of the dimensions and positions of parts, to make them to work together properly. This is a continuous battle in this work, with no simple, or general, attack plan available. Sometimes early-on minor mistakes, or botched details, can cause big problems in fitting things together later. Other times, what may appear to be big problems are surprisingly easy to solve. The following photos of a range of fitting operations were taken at Muscle Car Restorations, Inc., in Chippewa Falls, Wisconsin.
The only general advice that applies to these things is: You minimize the potential for big problems when you attend to dimensional accuracy as you go along.
When it is done correctly, quarter-panel replacement can be a long job. This is work that can be done very well or very badly. Doing it well involves making everything fit nicely, while avoiding forcing fits in any major way. Such forced fits can cause distortion in the finished job.
The first step is to plan exactly what metal you want to remove and replace. In large part, this is dictated by the damage that is the cause for having to graft in the new metal. It is tempting to replace all of the old metal that is included in the new panel that you are installing—after all, you paid for all of it—and often, this is the best way to go. It all depends on the soundness of the old quarter panel, the quality of the replacement panel, and the logic of where you have to weld in the new metal. It is possible that there are features of the old metal that are sound, making them superior to their counterparts in the replacement panel. This may be the case with regard to the positions of character lines, or of accessory mounting points that have to match other features in surrounding panels. Every partial panel replacement has its own logic and imperatives. Where you cut and weld in new metal may be an easy decision, or it may take considerable forehead-wrinkling thought.
Part of this quarter panel’s lower section had already been removed to gain access for a structural repair to part of the unibody. Now, tape was applied to it to indicate the cut line for removing the rest of the quarter-panel metal that would be replaced.
Cutting out a quarter panel with a plasma arc torch is fast and accurate. With a car stripped as far as this one is, there is no reason not to use this technique for this job.
The almost-removed quarter panel is shown here, dangling (just for my photograph) from the rest of the body. Note that the worker is wearing gloves, a welding helmet, and dust mask. That kind of protection is a very good idea when you use a plasma cutter.
Even a good quarter panel can have problems. It pays to correct the obvious ones before you install it. This panel has bulges generated by stretched metal. Shrinking the metal with a shrinking hammer saves time later, when it will be more difficult to gain good access.
Any of the metal cutting techniques described in Chapter 4 may have a place(s) in your approach to cutting out an old quarter panel. One that is not described there, the old air-chisel method of separating large metal sections from panels, is pretty obsolete, but sometimes has a place in cutting out areas in some quarter-panel constructions. Plasma arc cutting is often the fastest and best way to sever old quarter-panel metal.
Any supporting structure behind a quarter panel that you replace must be repaired if it is damaged. Areas like inner wheel housing attachments must be confirmed for alignment and contact, before you weld in a new quarter panel. It is much easier to correct structural issues before a quarter panel is mounted than after. In most cases, any supporting structure behind quarter panels is at their edges. The exception is monocoque quarter panels, where a skin is stretched over structure during manufacture to give rear vehicle quarter areas added structural strength. An example of this construction is the Jaguar XK-E.
Here, you can see how rough this panel is. Unfortunately, there was no other choice for this application. Reworking this panel, before it was installed, saved time.
It is best to cut a temporary line into either the old or the new panel, for a trial fitting. After that, you can refine the fit of your seam and make your final cuts.
Although it is almost impossible to duplicate monocoque construction in repair or restoration work, dealing with it does dictate the use of special measures that are beyond the scope of this book. Just remember that if you ever encounter monocoque construction, you have to account for it. Semimonocoque rear quarters are fairly common. However, the amount of structural strength contained in the outer metal in these units is relatively small, and they can be repaired or replaced using conventional techniques.
A key to performing successful rear-quarter-panel replacement is the sometimes disappointing realization that reproduction quarter panels are manufactured to varying standards of accuracy and quality. A few are impressively good, while others are nearer to the junk category. It is necessary to know how accurate your replacement panel is, and to begin to correct any deficiencies in it, before you try to weld it into place. It is far easier to correct many of these problems before you attach new metal, rather than after.
Good panel fit is critical, before you attempt to weld in new quarter-panel metal. Usual practice is to hang and position the new quarter panel in place with Clecos, and then to weld it with lap (or occasionally with butt) welding techniques to the old metal. Your choices of welding technique and joint type depend on your situation, and on your skills. At the high end, this joint is performed as a butt joint with TIG equipment. In the middle range are lap joints welded with MIG equipment. And, at the low end are spot-welded lap joints that have to be slathered with filler to hide them. Chapter 8 describes the relevant fixturing and welding techniques for quarter-panel replacement, in detail.
No matter how careful you are in fixturing and welding in new quarter panel metal, there is always cleanup shaping work to do, after it is welded into place. The best way to minimize this work is to control heat buildup in your welded joints. Some of the tips in Chapter 8 help you to avoid unnecessary welding heat buildup. Anything that you can do to reduce it saves you time, by limiting metal distortion. This also improves the quality of your work.
Shrinking and stretching are often needed to make a quarter-panel replacement work. Remember, quarter-panel replacement is a fairly advanced job, one that should only be attempted after you have mastered basic metal working and panel welding skills.
Door re-skinning was once a fairly common procedure in automobile repair and restoration work. About the third time that I re-skinned a door, I did it right, and was able to complete the job acceptably and in a reasonable amount of time. Those first two times…well, I don’t want to talk about them. Let’s just say that a Three Stooges comedy routine has nothing on them, except possibly being funny.
In recent years, door skinning has become pretty rare in collision work, but it is still performed some-times in repair and in restoration work. The reasons for the decline of this procedure will give you some idea of the problems with it. The first is the availability of decent new door skins. The ones made by OEM manufacturers tend to be expensive. They also can be hard to find for older vehicles. The door skins sourced from aftermarket suppliers are often more trouble than they are worth. Simply put, they frequently do not fit very well. It can take enormous amounts of labor to make them fit properly and look good. Due to their light construction an emphasis on weight reduction modern doors are often damaged in collisions to the point that re-skinning them is uneconomical. It requires so much work to straighten their frames, (or cores, as they are called in the industry), that the labor cost in these jobs makes replacement with new, or salvage doors, look pretty good. That, at least, is increasingly often the conclusion of most insurance companies. In many cases, they simply will not pay for door re-skinning.
Door re-skinning is still done in restoration work, but many restorers prefer to use salvage doors if they are available in reasonable condition. If rust is the reason for re-skinning a door, it is likely that the core requires so much work to make it sound that a salvage door looks like a better alternative. Still, there are times when door re-skinning is the best or only way to go.
The first imperative in this work is to start with a good door skin. Avoid economy skins like the proverbial plague. After you have removed the subject door and stripped it of all removable parts trim, door handle and latching mechanism, window regulator, window tracks, wiring, etc.—it is time to remove the old skin. After you have removed the spot welds that secure the skin to the door by grinding, drilling (with a spot-weld cutting drill), or disc sanding them away, you are ready to remove the original door skin. This can be accomplished by various methods, including edge grinding, seam chiseling, or seam prying. Special pliers-type devices that are sold to remove door skins work well to unfold door skin edges from door cores.
Carefully grinding the fold-over edge of the old skin is often a good gambit for starting the skin’s removal. A grinding wheel or a disc sander outfitted with 24-grit abrasive is a good setup for this job. If you go this route, be careful to stop grinding or sanding just as you go through the old skin’s folded edge. If you work slowly and watch carefully, you should be able to see a dark, early separation line appear in the folded metal as you cut through it. Be careful to stop grinding before you grind into the core’s flange area.
Spot welds between the core and skin in the door handle area are common, so look for and remove them. Some doors have internal bracing, particularly in their upper areas near the window edges. The spot welds that attach these braces to the door skin will have to be broken. Grinding carefully through the skin is one way to get at them, without destroying metal that will be needed later to attach the new skin. Sometimes these attachment points can be cut apart from the top, after windows and their trim have been removed.
After the old skin is removed, either by grinding its flange or by prying its edges back, all metal and weld residues must be removed from the core’s flange areas. They should then be straightened, ground flat, and smoothed, as necessary.
The new skin should be held in the door opening and visually checked for contour match against, and fit to, the metal that will surround it. Then it should be checked against the core. If you discover any damage to the core, it must be corrected before you try to fit the new skin to it. If the skin does not position on the core naturally and easily, you have to determine whether the problem is in the skin, in the core, or in both, and correct it.
Almost all skins come with the 90-degree closing bends already formed at their bottom and side flange edges. A skin of this type may have a top bend that slips over the core, or it may not be configured that way. In either case, a good skin should slip into place over its core easily and authoritatively. Some skins allow for limited adjustment of their positions on their cores. These allow some movement of the core within the skin’s edge bends, after those edges are partially or fully closed over the core. This movement is only possible before they are welded, or otherwise permanently fastened, to their cores.
Skins of this type have to be positioned in the door jamb before they are fully attached to their cores. This usually is done by temporarily hanging these doors, before final flange closing is completed. At this point, it should be possible to move these skins on their cores vertically, laterally, and diagonally by small amounts, to make them fit properly in their door openings and to make character lines align. You will not have much movement to work with, but there should be some. These types of skins are moved on their cores by very carefully tapping their edges with soft tools. Hammering on wooden blocks held against them, or tapping them with plastic mallets, often works well for door skin final positioning.
To close the bottom and side skin flanges over the core, you make your bends; working from the center of each area, outward, in both directions, to the door’s corners. That sequence helps to avoid distorting, buckling, and stressing the installed skin.
In some configurations, the tops of skins are positioned and secured by the bracket areas that you may have ground through when you removed the original skin. In these cases, the new skin will have brackets or flanges that mate to them. These may be adjusted for skin-to-core gap, and then secured with sheet metal screws or by welding them. Once this is done, the door skin flanging can be completed. There are several ways to do this. You can move re-skinning pliers along skin flanges to close them. This gives you finer control. There are also pneumatic crimping and rolling tools available that are much faster than closing pliers, but offer less control as you move along with final seam flanging.
No matter how good your flange closing tools are, most re-skin jobs still involve limited use of the grand-daddy of all closing tool sets, a door skinner’s hammer and a dolly (or block of wood) to finish and refine some of the areas of your flange.
There are two possibilities for bonding a door skin to its core: You can spot or plug weld it into place, or you can use adhesives to bond and seal it.
Modern practice is to use adhesives to attach skins to cores. These adhesives are special two-part materials that are designed to adhere skins to cores, and to seal them. They should be applied to both sides of the core’s flange, that is, to its out-side before it is lowered into the skin, and to its inside flange before the skin is crimped or bent over it. These adhesives have reasonably friendly cure times, but don’t plan on any extracurricular activities too soon after you have applied them. Door skinning that is performed this way often involves two or three people, and those people tend to move pretty fast, once the adhesive has been applied. Multiple tools are often employed to bend the skin’s edges over its core.
The other method of adhering skins to cores is to weld them in place on their bottom and side edges, after those edges are fully closed. This can be done with spot, MIG, or TIG approaches. Attachment welds should be made at intervals of every few inches, along each bottom and side seam. No prizes are awarded for making excessive numbers of welds. In restoration work, the number and spacing of welds should be as close as possible to the original configuration. While it is possible to spot weld skins to cores, this requires special equipment, and has no particular advantage. Plug welding is often used in restoration work to secure skins to simulate the appearance of original factory spot welds.
New skins come primed on both sides. Be sure to paint the inside of any skin that you mount with a water-proof and resilient paint, before you install it. It is critically important to remove all rust from the flange areas of cores, and to paint them, before you install new skins over them. I recommend a good weld-through primer for this application. Also apply seam sealer to the critical folded area of the skin, after it is installed.
Over the years, there have been so many different ways that door hinges and latches have been configured and adjusted that it is impossible to describe all of the major ones here. Door hanging has aspects of art and science about it. I have no statistical proof of this, but I have noticed that the people whom I have known in body shops who were really good at this job hung it perfectly right on the first or second try also tended to be excellent pool players. Like pool, hanging vehicle doors involves manipulating several variables in your head, simultaneously. This is because every adjustment that you make may not only change the factor that you are adjusting, but one or more other dimensional factors, as well.
The first step in adjusting doors is to understand the logic of the particular system that you are adjusting. Basically, you usually have two hinges to adjust. In the best situations, each can be moved in, out, up, down, and back and forth. This can be done with threads, washers, shims, cams, or sliding plates, among other possibilities. With welded hinges, after you run through the possibilities on the removable side attachment, your options may be limited to bending the metal that supports the welded attachment side. When both sides are welded and only hinge pin removal is provided for door removal, bending the hinge-mounting metal becomes your only recourse.
The same motions and movements that are used for adjusting hinges are possible for adjusting door latches and latch receivers, with similar configurations of their hardware. And that is only the beginning of the possibilities. In older cars, body shims between bodies and frames were often used in making doors fit properly. That’s right, you sometimes had to reposition the hinge and latch posts, themselves, to make things line up correctly.
Most door fitting involves making multiple adjustments to hinges and latches, to have everything properly lined up. Each adjustment should improve one factor, generally reducing misalignment there, until perfect alignment is achieved when all factors are accounted for and properly adjusted. At every stage of these adjustments, this puts a premium on knowing exactly where things are in relation to where they were, and where you want them to be.
Any technique that you can make work for sensing alignment makes the job easier. This may involve the use of reference tools, like straightedges, to check surface alignments. Or, it may require eyeballing, or feeling surfaces, to spot deviations from proper alignment.
One of the problems in making door and other panel adjustments is that as you come closer to a final result, the necessary changes become smaller and smaller. Most adjustment systems do not particularly accommodate very fine, incremental adjustments. It may take several attempts to make an adjustment right, without destroying some other aspect of panel alignment. It all takes clear thinking, good manual technique, and even a bit of luck. Luck isn’t absolutely necessary, but when you have it, it speeds this work along.
Mounting and Adjusting Trim
Mounting trim has the same, basic consideration as hanging panels you want to make everything line up. Over the years, in the quest for invisible ways to attach trim, manufacturers have developed and adopted a dizzying variety of methods for affixing trim to panels. Some are pretty straightforward, while others range from amusing, cumber-some, or difficult, to downright stupid. Modern trim is often affixed with adhesives, which has the distinct advantage of not puncturing paint and metal, thereby removing a potential source of rust. Otherwise, various types of plastic or metal clips, threaded fasteners, expanders, and the like have been, and are, used to attach it. Snapping, sliding, and pivoting motions often are required to affix and to remove it.
Small adjustments to trim position can involve modifying trim clips, or other attachment items, by bending, filing, or grinding them. Where new metal is involved, it is necessary to puncture it for most trim clip attachments the exception being the attachment of trim to the edges of panels.
Some trim attachments are adjustable, with slotted bolt-through configurations, and other methods. At times, after structural and panel repair, adjustments of this sort do not provide sufficient range for proper alignment. In those cases, either the adjustment or the mounting point has to be modified to make trim fit properly.
As with other alignment propositions, final fit must be determined visually, by feel, and by the comforting sense that everything looks right.
Written by Matt Joseph and Posted with Permission of CarTechBooks