Building a 1/32nd Scale Slot Car: Group 44 TR3

By Michael Ashton

In my younger days I owned four Triumph sports cars, including a TR3. So when a Lindberg TR3 static model kit “fell” into my possession I decided to make my first attempt at building a 1/32nd scale slot car. At first I thought that I would make a replica of the TR3 that I knew and loved. However, as with many slot car enthusiasts, I am not particularly interested in street (non-racing) versions of automobiles. But if not my trusty old TR3, I wanted it to be something worthwhile historically.

After a fair amount of Internet research on who has raced the Triumph TR3 it became obvious to me that one of the Group 44 racing team’s cars would be a great example. Most notably the TR3 built and driven by Brian Fuerstenau. Along with the more famous Bob Tullius, Brian was a cofounder of Group 44 Racing. He was a self-taught automotive genius who could make Triumphs, Jaguars and many other sports cars of the era perform uncannily well. And he was a champion driver at the national level long before Group 44 came to be. Sadly, he died in 1993 when the T-6 aircraft he was piloting (his other passion) crashed.

One thing is certain: no matter what form of motor sport Brian Fuerstenau would have been involved in — whether at Le Mans or a dirt track in the Ozarks — he would have competed at the top level. I hope that my humble attempt at recreating his rustic ride as a slot car would have met with his approval.

© Copyright Don Struke. Used with permission.

© Copyright VIR History. Used with permission.

The Model

Notes on the Process

The basis for the project was the Lindberg Triumph TR3 static plastic model kit.

The body is reasonably scale accurate, however, it has only rudimentary detail. Now my modeling skills and experience are quite limited. Therefore techniques such as cutting, filling and reshaping body details are beyond my capability — at least for now. So I have to create the illusion of detail using the primary assets that I do possess, namely tenacity and patience. Following are some of the techniques that I used.

For me, the most difficult task was the creation of the tonneau cover. The TR3 cover is unusually difficult because it has multiple surfaces (top and sides) and must conform to a number of undulations around the entire cockpit. I experimented with several methods and materials including very fine grit wet/dry sandpaper and surgical tape. I literally stumbled on the solution that I used while wandering around a craft store.

Chalkboard tape has the ideal characteristics for the TR3 tonneau cover: It has almost perfect color and texture; it is reasonably malleable but very strong and tear resistant; it is self-adhesive which is particularly useful during the fitting process.

First cut a strip long enough to cover the entire cockpit, as shown below.

Next, remove the backing exposing the adhesive side and press the tape all around cockpit edges. This will leave an impression of the cockpit’s geometry in the tape. You can also trace the required outline onto the surface of the tape with a pencil before removing the tape. Remember, this is chalkboard tape — the pencil lines erase easily.

Now it is relatively easy to perform a rough cut of the cover with sharp scissors or a hobby knife. Leave extra material around the outline to allow for test fitting and subsequent fine trimming. The fact that this is adhesive tape that can be easily removed and repositioned helps immeasurably here.

Once the tonneau cover shape is correct and conformed to the cockpit edges, the tape adhesive around the edges is removed using solvent and a Q-Tip. The cover is then glued in position with a permanent adhesive. I used two-part plastic epoxy. Be careful to keep the glue away from the outer most edges of the cover to avoid marring the car’s painted surfaces.

I found it almost impossible to create the tonneau cover snaps using paint. I just could not create tiny uniform circles by any method. So, I used tiny pins that I found in the sewing and jewelry sections of the local craft/hobby store. The pins on the left were used to simulate the tonneau fasteners while those on the right were used for the windscreen snaps and the roll bar opening covers.

The heads of both pins were too large to my eye so I reduced their diameter with a Dremel sanding disk. Correct spacing was achieved by creating a template from a narrow strip of masking tape with the fastener positions marked equally spaced on a guide line. The tape was then positioned around the edges of the cover and marked with a sharp scribing tool. I used a pin vise with the smallest available bit to drill tiny holes through the template, cover and cockpit edges.

The pins were then cut to a few millimeters in length and pushed all the way into the holes.

Enough of the pin protrudes through the inside of the cockpit (not visible externally) to allow CA glue to be applied from the inside, avoiding any glue residue showing on the cover itself.

Another area that required a little ingenuity was the kick panel behind each door. The Lindberg body has only the faintest relief detail of this feature (see the following photo) and it was not symmetrical on both sides.

I probably made a mistake by not addressing this prior to painting the body. I tried several types of matte silver paint, but even after allowing up to week of curing time, the silver paint never dried properly and tended to rub off — even under the clear coat! Then I remembered that I had bought some silvered copper tape to apply to the rails of my track.

The tape had the perfect, durable finish that I was looking for and a very effective adhesive. I was able to cut the exact shapes that were needed and position it precisely on the body. To make sure that the bond would be permanent and could withstand rough handling I applied some two-part plastic epoxy cement along the inside of the lower and trailing edges. Finally, two coats of clear coat were added locally for protection.

Decals were home made, printed on Testors clear decal paper using a medium quality inkjet printer. I was able to zero in on the appropriate type sizes by test printing on plain paper, cutting out samples and tacking them in position on the body. The dashboard gauges are drastically reduced images similar to TR3 gauges available on the Internet. The finished decal sheet received a light coat of Testors clear coat and allowed to cure for at least a week prior to application.

Microscale solutions were used to optimize the decal application. Micro Set to apply and create good adhesion to the surface. Micro Sol to allow the decals to conform to surface details and minimize edge visibility by softening the decal substrate.

Ranking high under the topic of “the illusion of detail” is the highlighting of chrome plated fixtures. The Lindberg model has no chrome plated surfaces or parts at all. And I have never found a chrome paint that was able to create a realistic looking finish (although Testors comes close). Luckily there is a product called Bare-Metal Foil that makes realistic chrome detail on any model possible.

It is a very thin foil with an adhesive backing that is basically burnished onto the surface and then trimmed to the desired area. No special tools are needed beyond a sharp hobby knife, Q-Tips and tooth picks. Reasonable dexterity and patience are a plus.

The chassis used to make this model a slot car is the Slot Classic. This is a very simple plastic chassis with an adjustable wheel base, designed for the standard Mabuchi [type] FC-130 motor.

The chassis for the Group 44 TR3 is outfitted with:

• A ScaleAuto 10K RPM FC-130 motor. Very mild but appropriate, I think, for this model.
• Slot.it axles, gears and bushings.

• The guide and pickup braids are Ninco Standard Suspension and ProRace tinned, respectively.

• Aluminum setscrew wheels and resin-cast inserts are BWA.

• The inserts were first sprayed with automotive primer then finished with Krylon matte aluminum paint.
• Tires are Ninco Classic 20x7.

Other Details

The driver figure is made by MRRC. It is the same figure that is used in many MRRC models, most notably, the 427 A/C Cobra. The head was repositioned to a more natural attitude. The figure was first primed and then painted with acrylic paints.

The Lindberg TR3 body was primed with DupliColor white primer and finished with DupliColor Ford Pure White.

The clear coat is Pledge Floor Care (formerly known as Future). This provides an attractive finish and also protects decals and Bare-Metal Foil chrome accents. It is easy to apply with a 1/2” soft bristled art brush.

This article covers many of the techniques employed and issues encountered in the building of this slot car. Feel free to post any questions that you may have in the comments section and I will do my best to answer them. You may also have suggestions about better ways to do things which are, of course, welcome.

_Michael Ashton