TOOLS & MATERIALS
 

Most models of current open-wheel race cars (single seaters) have the bodyshell and interior cast in "white-metal", a soft metal alloy that can easily be filed, sanded, and bent, if necessary. The suspension and some wing elements will be made with photo-etched (more correctly, chemically milled, but p/e is the accepted term) brass or stainless steel. Models of older cars, especially those with less of the suspension exposed, tend to be cast in resin, but the techniques for both types are essentially the same.

Both are cast in relatively soft (very soft for many resin kits) two-part rubber moulds that can leave "mould lines" on bodyshells and small pieces, and possibly some thin "flash" (excess casting material that's been forced out between the two-part mould faces) in the cockpit and axle openings.

The tools needed for 1:43rd

scale models are really very simple (photo 1). Small, fine-tooth modeller's files in flat, knife, half-round, and round shapes will be required for metal kits; they will work on resin too, but common "emery boards" (the fine-grit coated cardboard sticks made for filing fingernails) work very well and can be discarded when they become clogged up with resin dust.

Wet-or-dry sandpaper (320, 400, and 600 grit) is used to smooth out file and emery board marks; yes, it will work quite well on white-metal castings. A modeling knife (X-Acto type) will be needed to do rough trimming or cut parts from their "trees"; the blades will cut white-metal and old ones that are too dull for plastic kits are fine for white-metal. Other necessities include tweezers (a couple of styles/sizes), small scissors, some "holding tools" like clothespins or forceps,

toothpicks, paintbrushes, and the usual "miscellaneous" modeling tools.

Plastic model glue will not work on these kits; you'll need to use either alpha cyanacrylate (ACC, or "super-glue" (ZAP025) or epoxy (ZAP037) (photo 2) to hold major components together (GPM stock a range of them) and a clear water-based adhesive like Micro "Kristal Klear" (MSKK) for "windows" and tiny trim pieces.

Finally, you will need some putty to fill larger bubble holes or surface blemishes; I recommend a two-part epoxy putty (A + B in the U. S., Milliput in Europe), because lacquer-based auto putties will continue to shrink for months- epoxies won't.

photo 1

The tools required to build resin and white-metal kits are the same as those required for most types of models and are neither elaborate or expensive.

photo 2

Both white-metal and resin kits require either epoxy or "super glue" to bond the parts together - plastic cement will not work.

PREPARATION
 

Relatively few examples of a 1/43 scale white-metal or resin kit are made, usually something like 300-500 copies compared to 40,000 to 100,000 mouldings of a plastic kit, and when they are sold out, they're gone. So examine a kit immediately to make sure all the parts are there - neither GPM or the maker may have any spare pieces a year from now.

Quite often a 1/43 scale kit will include parts (especially p/e parts) for more than one version, so first read the instructions and figure out just which pieces you'll be using! I begin an open-wheel model by opening up the suspension mounting holes with a pin-vice and small drill bit (photo 3). These are often indicated only by small indentations in the casting and may be "lost" if you file and sand mould lines first.

Often lower body sections must be cast separately to model the complex shape of a modern Formula or Indy-car body accurately; glue as

much of the body together as possible and fill to join lines (photo 4) with putty. Remember, though, that interiors, engines, and other small bits must be added after the body is painted so don't glue a panel in place that must be fitted after something like that.

Files are needed to remove the mould lines (inside and out, if necessary) from white-metal bodies (photos 5 & 6). Once I've filed a mould line away, I sand the "filed" area smooth with #320 and #400 sandpaper (photo 7); yes, white-metal can be effectively sanded!

photo 3

Drill out the holes for the suspension mounts before beginning cleanup of white-metal bodies. Use small drill bits in a hand-held "pin vise". Note the seam where the lower nose section has been glued in place. Also note the small mould line inside the air scoop which must be filed off.

photo 4

Glue as much of the body together as you can-- remember that engines, interiors, etc. must be fitted later-- and fill the seams with putty.

photo 6

Half-round files work best for removing mould lines from the inside of body shells.

photo 5

Small modeling files are needed to remove the mould lines and thin flash found on even the best white-metal castings.

photo 7

File marks are large gouges in 1/43 scale, so sand all the filed areas smooth with successively finer "wet-or-dry" sandpaper.

Emery boards make perfect "files" for resin bodies (photo 8) and can be cut to get inside small openings (photo 9). Don't forget the small mould lines on wheels, mirrors, seats, and other small components. If you have a variety of file shapes, one will work on just about any white-metal casting (photo 10).

If, in sanding the body, you've partially filled a panel line, re-scribe it by first making a cut with the sharp edge of the knife blade, then pulling the back (flat) side of the blade through the cut to re-scribe the line (photo 11).

photo 8
Open up any required holes in vac-form pieces before cutting it to shape.

photo 10
Apply adhesive for vac-forms with a small, thin paintbrush. If necessary, glue one side in place and let it dry overnight before gluing the second side.

photo 9
Apply adhesive for vac-forms with a small, thin paintbrush. If necessary, glue one side in place and let it dry overnight before gluing the second side.

Don't forget to open up the hole for the screw(s) that attach the baseplate to the body with a small drill (about #60); the "cast in" holes are never deep enough.

The final step in preparation is washing the pieces to remove both the mould release agent and oils from your fingers. I first soak the pieces in warm water and dish-washing detergent for a half-hour (or more), and then scrub them thoroughly with an old toothbrush before rinsing in hot water. That - especially the soak - seems to be the key to obtaining a good clean surface.

photo 11
Rescribing panel lines.

PRIMING, FILLING & PAINTING
 

White-metal kits must be given a coat of primer before being painted, and I highly recommend the same for resin kits. Any visible large surface blemishes or bubble holes should be filled with putty and sanded smooth before the primer coat. An artist's palette knife (photo 12) is very useful for applying putty. Be sure to select a primer that will be compatible with the final colour paint; don't use an enamel primer if you plan to use lacquer colours. I prefer lacquer primers since they dry quickly and lacquer, enamel, and acrylic paints can be used over them. Primer should be sprayed on - I prefer using an airbrush but aerosol cans will work if used carefully.

The first primer coat will often show you small imperfections and, in resin castings, tiny bubble holes ("pinholes") that you couldn't see in the bare surface. Small holes can be and a white-metal body (top) whose minor blemishes and file marks were eliminated by simply sanding the surrounding area, leaving primer in the blemish. The same technique (sanding to bare metal) can be seen in photo 15. Extreme cases (rare now, but common with older kits) may require

sanding off most of the first, or even the second coat of primer before the surface is completely smooth (photo 16).

A good smooth finish is absolutely dependent on a smooth primer surface, and I use 2400 and 3200 grit sanding cloths from a model car "polishing kit" as a final step before painting the body. There have been several good pieces in FSW on painting, so I'll just repeat that a smooth primer surface is a major factor in a good paint job. I use a simple spray stand that lets me hold it to turn and twist the model while painting, and I sand the surface between coats (photo 17) with 3200 and 4000 grit sanding cloth. Decals, too, are a subject best treated separately.

photo 13

Small blemishes like these bubble holes may not be visible until after you've applied a primer coat. It's easy to fill them with a drop of primer, but a second application may be necessary after the first has dried.

photo 12

A palette knife, trimmed to a trowel shape, is very useful for applying putty.

photo 14

Large blemishes in the lower bodyshell have been filled with putty, while tiny ones in the upper shell were "filled" by simply sanding the surrounding area to bare metal.

photo 15

The body casting of this Precision Miniatures Novi had many small "blemishes", but none large enough to require filler. Simply sanding the general area to bare metal and spraying on another coat of primer produced a smooth surface. Some models may need to have this repeated a couple of times.

photo 16

Although this model had no major surface blemishes, almost all the primer coat had to be sanded off to fill smaller ones; note the darker primer remaining in many small spots.

photo 17

Sanding the paint between coats will not only get rid of any trapped dust motes, but will give you an even smoother surface.

Open-wheel cars also have open cockpits, which play a major part in how realistic a model looks.

No interior is a single shade of "flat black"; upholstery, painted surfaces, padding, steering wheels, and other components all have different shades and textures. "Flat Black" acrylic paint looks different from "Flat Black" enamel, and "satin" shades are different yet. I like to use a softer, more "grey" shade for steering wheels, dead flat black for instrument panels, satin colors for seat belts and semi-gloss shades for upholstery, for example.

It also helps to use different kinds of paint; water-based acrylics can be applied over both lacquer and enamel (and vice versa) without

eating into the paint under it, and excess paint can be removed with a toothpick.

Always bend photo-etched pieces to shape (photo 18) before painting either the belts or the seat.

If the seat belts or instrument panel are "3-D" etched "chrome" (really stainless steel) pieces the "hardware" can be brought to life by painting the belts (without primer) and then simply scraping the paint off the raised buckles (photo 19) with the point of a sharp knife. Different shades of aluminium, steel, and other metallic colors can really bring out cast-in engine and transaxle details, too.

photo 19
Simply scrape the paint from the raised buckles if the belts are made from stainless steel.

photo 18
Bend photo-etched seat belts to conform to the shape of the seat before painting. The "hardware" on p. e. brass belts must be picked out with silver paint.

BITS & PIECES
 

Most modern open-wheel cars have relatively flat (really aerofoil-shaped) suspension arms that can be very realistically duplicated with photo-etched components. Some kits, like those by Tameo, have powder-coated suspension pieces for a very durable and realistic finish. The suspension arms on cars from the mid-1970's back were usually fabricated from round steel tubing, and realism suffers if flat etched parts are used for those. Cast metal parts, though requiring some additional work to polish, definitely look better.

I use the time between coats of body paint to build up sub-assemblies, polish small pieces, try to get everything ready for final assembly. White-metal parts can be polished to simulate "polished metal" pieces (surprise, surprise) and even chrome-plated components. It's easy to bend or distort long thin suspension arms, roll bars, and similar pieces while polishing them, though, so I place them on a piece of thick glass (photo 20) while buffing them to a shine with steel wool. Initial

polishing of stronger parts can be done more quickly with a soft wire brush (photo 21) chucked into a Dremel Tool.

A final polish with Simi-Chrome or a similar metal polish will leave a white-metal piece shining as brightly as chrome. Although I prefer to assemble "wings" before they are painted, often that's impossible. I cut a toothpick to a flat, "chisel" edge, and use that to apply a thin bead of glue to the slot etched into the wing endplate (photo 22) and then carefully hold each element vertical until the glue sets. Fit all the wing elements to one endplate, then start at the top or bottom of the other endplate, making sure each element is in its proper "slot" before going to the next.

photo 20

Support delicate white-metal pieces by laying them on a piece of thick glass while carefully polishing them with steel wool.

photo 21

Sturdy white-metal pieces can be polished easily with a soft wire brush in a Dremel Tool.

photo 22

Use VERY tiny amounts of glue to attach one wing element at a time to a sideplate; when all are in place, carefully add the other sideplate.

Large photo-etched pieces can be cut from their "tree" (the metal framework that holds them) with small sharp scissors or (photo 23) with a knife. A sharp knife works best for small pieces; place the "tree" on a hard surface and hold the piece being cut free with a toothpick (photo 24), and simply cut through the thin tab holding the piece. If you don't hold the piece being cut free, it will most likely simply pop off into another dimension, never to be seen again, when the cut is made.

photo 23
 

A simple spray stand, made from a piece of wood and four pieces of spring-steel "music wire" will let you turn and twist the model to get paint into all the small nooks and crevices.

photo 24
 

Sanding the paint between coats will not only get rid of any trapped dust flecks, but will give you an even smoother surface.

Older kits often have upper and lower A-arms and uprights as separate pieces, but most current kits have the entire "corner" made from one photo-etched piece (photo 25) like the Tameo Williams shown. It's a simple matter to fold the two A-arms over and add the brake discs, callipers, and air ducts to make a strong and realistic suspension unit.

Take the time to study the instructions before you make the first fold, though - if you fold an arm the wrong way, it will most likely break off if you try to bend it back in the right direction. I place a small drop of glue in each of the lower A-arm mounting holes (photo 26) and then

insert the "pins" on the ends of the A-arm.

When that's set, I insert the upper A-arm and shock absorber pushrod into their mounting holes, but do not glue those at this point. The rear suspension (photo 27) of Tameo's Williams FW-18 is especially easy to build up, as it all connects to the engine; most kits are a bit more complicated.

photo 25

Most current kits have both A-arms, the upright, and shock pushrod all in one photo-etched component. Although it can be tricky to get all those "pins" in the corresponding holes, the resulting suspension is both sturdy and realistic.

photo 26

Apply a small drop of glue in each mounting hole for the lower A-arm and fit that in place.

photo 27

Fit the upper arms into their mounting holes but do not glue them in place at this point.

The same procedure is used for the front suspension, though it gets a bit more tricky here. Counting the "barge board" mounts, there are no less than nine (9!) pins (photo 28) that must fit into locating holes for each front corner!

Once you've glued the lower A-arms in place, the upper arms can be gently "tweaked" to mate up to their holes and the barge board mounts can be glued to the body. Once you have all four corners attached at the bottom (photo 29), the front wing and tyres will have to be added before the "ride

height" can be set.

Tyres, whether rubber or black resin, should have the mould lines and feed tags (the "nubs" where the tire has been cut away from the "sprue" of material that formed it) sanded off (photo 30); emery boards work very well for this, too. If the sanded surface of a rubber tyre is unrealistically rough, apply a coat of water-based acrylic semi-gloss clear paint. Decal sidewall logos can be blended into the tyre by a coat of semi-gloss clear, too.

photo 29

At this point, all four corners are attached only by their lower suspension arms, so the angle of the arms (and uprights) can be easily adjusted.

photo 28

The front suspension will attach to the body, and the "barge boards" add a complexity factor. Mounting rods and edges will be "touched up" after everything is glued in place.

photo 30

Mould lines on both rubber and resin tires can be sanded off with an emery board.

FINAL ASSEMBLY
 

Most modern kits provide an assembly sequence, but don't follow that blindly - look everything over and think about what parts must fit where before gluing anything. I personally prefer "super glues" because they set in seconds and need only a very thin film of glue between the pieces. Super glues can be hazardous - sloppy application can lead to fingers glued to the model, or to even worse places. I use the "thickened" super glues because their application can be controlled

better and their 30 second "cure" time allows me to move a piece slightly if necessary.

And I always have a bottle of de-bonder on my bench! Epoxy is the only other reasonable alternative- it's safer, but does take at least 5 minutes to set, and leaves a noticeable thickness of glue between the pieces.

"Ride height", the distance a model sits above the ground, is often of too much concern for open-wheel models. With

the ride height of most Formula One cars measured in millimetres, it can't be duplicated precisely in 1/43 scale, and often attempting to do so will introduce more obvious visual errors.

Before beginning to "tweak" your model, look at photos of the real car at rest (unless you're doing a diorama, of course) paying particular attention to the angle the suspension arms (especially the front ones) make with the body. The correct "look"

of the suspension and how the tyres "sit" are critical to the overall appearance of an open-wheel model. Autocourse photos of the Williams FW-18 showed that the suspension arms were essentially horizontal and parallel to each other with the car sitting in the pits sans driver.

Place the model on a flat surface (my piece of heavy plate glass gets used for this, too) and you'll usually find one wheel lifted well off the "ground plate" (photo 31). Make sure all the upper suspension pins are in their proper holes, then either bend the offending tyre down, or move the diagonal rear one up (or both) until all four tyres touch the ground.

Now check that they all sit

squarely on the ground; since the upper arms aren't glued, the wheel (actually, the upright) can be twisted about a horizontal axis to get its surface flush with the ground-plate. Of course, you may now have to tweak the suspension arms again!

Once the model sits squarely, touching the ground at all four corners, turn it over and apply small

drops of glue (photo 32) to the underside of each upper A-arm where it fits into the body.

This model, like many, required a compromise. In order to get the front wing and undertray right down on the ground (a scale, if not realistic-looking "ride height") the front suspension would have had to angle up several degrees. I chose to

decrease the deflection of the front suspension at the expense of a greater than scale "ride height" (photo 33); there's still a slight angle to the suspension, but the model doesn't look like an "off-road" vehicle either!

photo 31

The first time you place your model on a flat surface, it may resemble a dog at a fire hydrant. That's why the upper arms aren't glued in place yet!

photo 32

Once the model sits with all four wheels squarely on the ground, apply tiny drops of glue to the upper suspension mounting points.

photo 33

Compromises make a good-looking model; my finished model's suspension looks like what I see in photos and the "ride height" isn't unreasonably high.

If you get down for a "ground-level" look, the model sits slightly high at the rear but the more unacceptable alternative would have been to have the half-shafts angling "uphill". With all the detail pieces in place, and viewed from a more usual perspective (photo 34), the model really does look right.

Any small-scale model has many compromises; you just cannot view one from the same perspective as you see a real car. The "trick" then, is to decide which features are most important to you, and to get those "looking right" rather than strict insistence on exact "scale". Happy (1:43rd scale) modelling!

photo 34

Given the extreme complexity of a Formula One car, Tameo's kits do an excellent job of producing a very realistic model that's still easy to build.