Egress Jamie Booth replica

 

ORV stands for “Off Road Vehicle”, it is Tamiya’s first plastic space frame consisting of two halves screwed together. The chassis is a two-wheel drive, two-wheel steering chassis with rear swing axle suspension and independent front suspension for off-road use.

Tamiya designed the rear suspension system to provide excellent bump absorption with shock dampers that changed according to the model; but it is a weak point of the chassis. The front suspension system consists of torsion bars, which on later chassis versions included oil damped shocks due to its poor efficiency in absorbing bumps and the short suspension travel.

ORV has a rear gear box consisting of a plastic case with two alloy side plates. The gearbox is known to be a weak point because plastic and alloy parts flex too much to keep gearbox correctly assembled. Early versions were not equipped with a rear differential.

The positioning of the servos at the front but varies from model to model. The position protects the servos from external forces resulting in breakage.

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The originals

Three models use the first version of the ORV chassis:
1. Subaru Brat, item number 58038 released for sale in 1983 and available on the market until 1986
2. Lancia Rally, item number 58040 released for sale in 1983 and available on the market until 1985
3. The Frog, item number 58041 released for sale in 1983 and available on the market until 1988
There has been several re-releases of the Brat and Frog over the years, so far (2022) the Lancia Rally has not been re-released.

 

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This is a list of the main differences between the models with the first ORV chassis: Subaru Brat, Lancia Rally and The Frog.

  1. All three models have different bodywork and wheels/tires, the rarest is definitely the Lancia rally.
  2. Lancia Rally and Subaru Brat body material is ABS, and The Frog body material is Polycarbonate.
  3. Lancia Rally and Subaru Brat have one antenna while The Frog has two.
  4. Lancia Rally and Subaru Brat does not have a differential gear, The Frog has.

 

Detailed differences between the three originals, moving from front to rear of the chassis:

(See images below each section for more details)

1. Front torsion bars attachments
Lancia Rally and Subaru Brat front torsion bars have rubber on the screws that attach arms to the front bumper.
The Frog has brass tube on the screws that attach arms to the front bumper.
2. Skid plate
Only the Frog has an alloy skid plate under the front of the chassis frame. The early versions of the Lancia Rally and Subaru Brat chassis frames were missing holes for this plate. Tamiya after the release of the The Frog model also modified the Lancia Rally and Subaru Brat chassis.
3. Servo Stay
Lancia Rally and Subaru Brat have a large servo front stay.
The Frog has a slim-thin servo front stay.

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4. Front body mount
Lancia Rally and Subaru Brat have long front body mount.
The Frog has short front body mount due to body design.
5. Rear body mounts
Lancia Rally has the low rear body mount.
Subaru Brat and The Frog share the same body mount position, but of different designs.
6. Servo orientation
Lancia Rally and Subaru Brat have front servo turned 180 degrees compared to The Frog and all the Blackfoot family.
7. On/off switch
Lancia Rally and Subaru Brat have on/off switch mounted to the right side of the chassis frame. The Frog has on/off switch mounted to the rear part of the Polycarbonate body.

 

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8. Spur gear
Lancia Rally and Subaru Brat have a plastic spur.
The Frog has a spur made of plastic and alloy.
9. Resistors
Lancia Rally and Subaru Brat have two ceramic resistors mounted to the right side of the chassis frame.
The Frog has two ceramic resistors mounted to the back of gear box with an alloy bracket.

 

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10. Front bumper
Lancia Rally has a plastic + alloy front bumper.
Subaru Brat and The Frog have plastic front bumper.
11. Rear dampers
Lancia Rally and Subaru Brat have black friction damper.
The Frog has metal grey adjustable racing damper.
12. Motor and pinion
Lancia and Brat have a 10 teeth pinion on the 380 motor with alloy gearbox adapter
The Frog came with a 540 motor and the choice of 16, 18 or 19 teeth pinion.

 

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Re-releases:

This is a list of the differences between the original and the re-release Frog:
1. Speed controller
The original has the mechanical speed control + 2 x ceramic resistors
The re-release has the electronic speed control without ceramic resistors
2. Switch stay
The original has the alloy switch stay for the MSC.
As a result of removing the MSC, the switch stay is replaced by a simple reinforcement bar on the re-release.
3. Servos
The original has 2 x servo in front part of chassis and replacing the MSC with a ESC on the re-release also eliminates the need for the second servo.
4. Front suspension
The original’s has brass tube on the screws that attach arms to the front bumper is replaced by a step screw on the re-release.
5. On/off switch
The original has on/off switch mounted to the rear part of the Polycarbonate body.
The re-release has on-off switch mounted to the left side of the chassis frame.

 

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Later evolutions of the ORV chassis

Tamiya evolved the ORV chassis into the Blackfoot chassis released for sale in 1986, which is used on two models.
Improvements are:

  • re-engineered front suspension moving from torsion bars to shock absorbers and longer “a-arms”.
  • a new radio system cover
  • light grey chassis changed to red chassis
  • all the family has differential gear
  • larger wheels and tires

Four models have the first version of the Blackfoot chassis:

  1. Blackfoot, item number 58058 released for sale in 1986 and available on the market until 1992
  2. Monster Beetle, item number 58060 released for sale in 1986 and available on the market until 1993
  3. Mud Blaster, item number 58077 released for sale in 1989 and available on the market until 1992
  4. Bush Devil, item number 58101 released for sale in 1992 and available on the market until 1995

There have since been several re-releases of these models as well.

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Written by Gabriele Andreoni

  

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