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    • #21007

      This is a PGP+ class eligible model for our Pre War Coppa D’oro series. The main restrictions for this class (apart from the mandated motor) are a maximum track of 50.8mm (excluding inserts which may extend beyond) and maximum tire diameter of 23mm. Of course all tires must be DArt club series urethanes and wheels cannot exceed 16.5mm in diameter nor be wider than 5.5mm… so armed with that info we can begin building something eligible…The basis for this build was the DArt Auto Union C Type body kit with a few modifications and upgrades. As always I begin with the wheels which I modified by turning down a set of 4 DArt DA16x9XL alloy wheels. I carefully mounted 4 DA0210 club series tires using clear Gorilla Glue after scuffing the outer rim surface and let them dry overnight before truing with my Hudy. Using the truer I also narrowed the front tires using a sharp Xacto knife. After sorting the overall tire diameters I gathered some small bushings and the rest of the parts needed including the low power BWMS050 motor with a 1.5mm 10T pinion. Initially I also opted for an aftermarket 23T crown gear but then went with the orange 25T gear instead after initial testing. I opted for a simple torsion chassis using a combination of piano wire and brass.

      The front end would use stub axles made from piano wire with DuBro No2 steel washers soldered on one end. Because the washers were too large in diameter they needed to be ground down to fit within my front axle braces.

      I also fabricated the motor mount and guide sleeve. After sanding all of the parts I soldered the rear end together.

      Then I made the front section. The front and rear sections are only held together with piano wire tabs that slide inside a small brass tube.

      By gently pulling them apart (and out of the tube) you can separate the front and rear halves of the chassis which allows for convenient cleaning and maintenance. The wire tension is enough to hold it in place. Before final re-assembly I made sure to clean any flux residue before applying a blackening treatment to all of the chassis parts using a disposable dollar store brush. Make sure you are happy with the chassis – because after you apply the blackening chemical treatment to the steel you won’t be able to solder anything to it. While the steel does turn black the brass is more stubborn and will only give you an antique look at best – but I still prefer this to painting anyday – and I prefer to take away the shine of brass (or steel) especially on exposed parts that don’t reflect the real thing. I painted the wire wheel inserts that came with the kit and after final assembly I glued them in place using white glue. The assembled chassis weighs in at 45.7g..

      I wanted to use as much of a complete pilot and interior so I modified the original body by opening up the cockpit. I also extended the cockpit slightly by removing material up to the recess for the original windscreen (which I would replace with a more detailed windscreen from the DArt Type D body kit).The painted and washed body shell (without interior and exterior detail) now weighs 9.6g.

      Decals which I printed on clear Testor’s decal sheeting were applied. I also used Micro Mark decals for the front grill detail. Then I made firewalls which could be glued in place using thin styrene sheeting.

      Other upgraded parts included a pilot figure, head, steering wheel, shifter and interior side panels from the DArt D Type body kit, plus DArt button radiator cap and DArt fuel cap. After painting the body silver I added a black wash using Tamiya flat black acrylic paint diluted with Tamiya acrylic thinner to bring out more detail where I wanted it. If using the acrylic thinner (which is alcohol based) only apply carefully where you want it and let it pool and dry to give the desired effect. Quickly wick away any wash that creeps where you don’t want it since the longer it remains the harder it will be to clean away. Once it is dry it is impossible to remove easily – you’ll need to polish it out then.

      I would do the interior first. I would use clear 5 minute epoxy to fix everything in place, starting with the firewalls. Then came the seat back (minus head rest) and dashboard. While that dried I removed the lower portion of the pilot’s legs and sanded away the underside of his thighs to give me as much clearance underneath as possible. Luckily I did not need to shrink his torso. Once satisfied with the fit (and clearance) of the torso/legs I glued the pilot arms to the torso and placed the steering wheel in his hands and let dry. Then I glued the pilot’s body to the seat and let that dry. Then the side panels were fixed in place and finally the shifter was added. The interior was done. I could add a styrene piece underneath his legs to finish the interior but I’ll leave that alone for now. [Turns out the blackened chassis works nicely underneath so I decided to not bother adding a floor.]

      Exterior details were then added. The windscreen was second last – after hand drilling a pair of holes to fix it in place. Finally a solid aluminium wire was added to the rear of the body through another small hole hand drilled.

      The completed body now weighs 12.9g. Not bad!Add two screws and four urethane washers (2 for some body float and 2 underneath the head of each screw (to prevent the screws from backing out) and our completed model weighs in at 59 g.The original crown gear performed just fine when the chassis alone was tested (before the body was completed) but as fate would have it would fail on the first lap in its debut… but replaced and tested the model is very quick and this chassis shows lots of promise for 2022.Happy to answer any questions. If you would like to upgrade any parts on your C Type (like I did) drop me a line… Cheers!

      The Happy Canadian Scale Modeler!

    • #21010
      Avatar photoGI

        WOW !!  Beautiful work on the chassis and body by the Maestro.

         

      • #21011
        Avatar photoMiA

          Beautiful chassis, clever design, lovely detail work on the body, and that interior and driver!!

          Somewhere Professor Porsche is smiling!!

        • #21014

          Cheers! The chassis is a basic torsion/flexy chassis that can be taken apart to be cleaned.

          On a more serious note and assuming build quality is the same (everything is aligned and either parallel or square and moving parts polished, etc.) because it is a torsion chassis you can race it harder into corners and accelerate earlier in the middle of corners without the model upsetting. This is very different from a slab or straight chassis made from plastic, wire or aluminium which may go hard into corners but will struggle through and out of corners.

          Happy Building and enjoy the Christmas Break!

          Cheers!

          The Happy Canadian Scale Modeler!

        • #21017

          Two body posts into brass inserts… with countersunk steel screws… a touch of white glue to dry and help secure the screw plus a urethane washer between the post and chassis (for body float) and the screw head and chassis to keep it from undoing… not a bad use of half a pack of a $2.50 DArt product…

          The Happy Canadian Scale Modeler!

        • #21027

          Very pretty!

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