Bull Head

Model

Tamiya Bull Head, article number 58089 put on sale in 1990 and available on the market until 2003.
Styrene body.
Clod chassis.

Analysis of the model to be restored

This project started by winning a lot of material at an online auction; the material seems to be the parts of a Bullhead, these purchases are a leap in the dark because it is impossible to be certain that even rare parts are not missing and you cannot be sure that you are buying an original 1990s model. It is possible to find yourself with parts from a more recent re-release and even missing some parts, The photos below are part of the offer.
Starting from the front going to the rear, an analysis of the body reveals that

– the stickers are almost all present. In reality, this news has no influence on the decision to proceed with the purchase because the original sticker sheet that Tamiya reprinted for model number 58535 is still available on the market today (2024). The sticker sheet has the code 11425172 or 1425172. On the sheet at the bottom right it is easy to read ‘1/10 RC BULLHEAD 58089 (9495111-1425172) and at the bottom left it is easy to read “1990”. It is not possible to distinguish a sheet reprinted by Tamiya from an original sheet from the 1990s.

– all chrome-plated parts are present,
– no cuts, cracks, breaks or additional holes are present,
– the American flag is missing,
– the colouring conforms to the official one, but has seen better weather; the blue colour seems faded, it is not possible to say with certainty that TS19 metallic blue was used,

Starting from the left going to the right, an analysis of the chassis parts reveals that there are

– the four chrome suspension arms
– the red coloured Clod chassis typical of the Bull Head series only,
– the chrome-plated front bumper was damaged when someone peeled off ‘BULLHEAD’ stickers, taking away the chrome, fortunately the part can be covered by reapplying adhesive. The damage will certainly be noticeable, but it will not change the final result of the restoration. Analysing the parts it is clear that the vehicle was used before being dismantled and then probably stored in some cellar. It is not possible to restore a model that can be described as never having been used,
– the electronics carrier plate is complete with the chrome-plated L-arm for attaching the mechanical speed control servo, which is Part C2. This part is also present in the set number 58535 of 2012, but is listed as ‘useless’ as this model uses an electronic speed control. No one precludes the previous owner from installing it anyway.

– the front and rear drive train with the steering system,
– metal frame reinforcement plate installed at the bottom that was first introduced on this model 58089 and then used on all Clod chassis models released thereafter,

– the four + four dark yellow shock absorbers,
– the two + two dark yellow diagonal suspension arms,
– dark yellow front and rear bumpers,

It is really difficult to make a better analysis of the frame parts from these photos. The wheels are present and sold separately by the same seller. The rims are intact and all the chrome is present. The tread is intact and not worn, the wheels are basically clean. This confirms that the model was used sparingly; it was then dismantled and stored, one can only hope that there are no negative surprises.

Along with the above parts, there is also the mechanical speed controller with the double switch: On-Off function and selector for parallel or series power supply of the electric motors. When the electric motors are powered in parallel they guarantee higher speed with shorter battery life, when the electric motors are powered in series they guarantee longer battery life and lower speed. In the 2012 re-release, an electronic speed control is to be installed that has only one switch for the On-Off function.
This detail provides an initial indication that the parts in question appear to be part of an original model 58089 from the 1990s. In addition, there are:

– two electric motors with pinions
– servo for steering
– servo for mechanical speed control
– receiver.

Restoration

As soon as the package is opened, the first thing to do is to check whether the chassis bears the words ‘Made in Japan’ and the production date ‘1987 TAMIYA’; these details provide a further piece of evidence that the model is an original and not a later re-release. The quality of the image does not allow these two abbreviations to be easily read.

As a second operation, align the parts for inventory. The electric motors, electronics and mechanical speed controller can be seen at the top. The two front body supports identified as Part J6 are missing, a lack that will cost time and resources in finding an alternative.

Chassis restoration

Analysis of the parts confirms the first impression gained from the photos in the online advertisement; the parts are all intact, the chrome plating is not ruined, there are no scratches or special marks. Sequence of pictures showing the stages in which the frame is cleaned:
– wash all parts except the chrome-plated ones with hot water and degreasing kitchen soap and then run a cycle in the ultrasonic washing machine: metal parts for 25 minutes at 70°C and Teflon or plastic parts for 25 minutes at 40°C
– wash all chrome parts with hot water and degreasing kitchen soap, using a soft-bristled brush to avoid scratching the surfaces. Use a very low percentage of soap that could attack the chrome plating
– arrange the parts in such a way as to check again for other missing parts, this check confirms that ‘only’ the front body supports are missing. The gears are not worn and look like they just came out of production.

The following sequence of images illustrates the procedure for re-assembling the chassis:

– assemble the steering system, the Clod chassis has a system defined as 4x4x4 which identifies the 4 driving wheels and the 4 steering wheels; the front wheels steer in the opposite direction to the rear wheels, reducing the steering radius. This technical solution is made necessary by the diameter of the wheels that limit the agility of the Clod model. The suspension arms are long because the steering servo is installed in the centre of the chassis and the tie rods from the centre of the chassis reach the front and rear ends of the chassis,

– assemble the red chassis with the lower reinforcement consisting of metal plate and plastic plate,
– install rear cross member with towers to support the body,
– install front bumper including the two front lights,
– assemble the chassis with the previously prepared steering system,
– prepare the plate that includes the mechanical speed control, receiver and its servo,
– assemble the chassis with the previously prepared electronic carrier plate,

– following the manual, apply the front and rear stickers on the red frame (centre in the pictures below), the two side stickers ‘4x4x4’ (right in the picture below) and the chrome front bumper inscription ‘BullHead’, which is intended to partially cover the chrome damage (left in the picture below)

– it was not possible to trace the front towers alone for supporting the body. The two pins in question are chrome-plated and are part of the body.
These two towers are not available on the new parts market although they are present in the 58535 re-release and are not readily available on the second-hand market. The accessories market for the Clod chassis is practically endless, today (2024) it is possible to assemble a chassis without using original Tamiya parts, some companies have made available complete sets of towers for installation of the BullHead and Clod Buster bodies (left in the picture). Each package contains two rear towers (quite similar in the two models), two + two front towers (definitely different between BullHead and ClodBuster). With non-original accessories you can never be sure of the complete compatibility of the parts; therefore, the only possibility is to install the parts (centre in the picture) and check body installation (left in the picture).

Although these towers are not original they are very well made and in the absence of other solutions are the only way to
– assemble the front and rear drive system, which also includes the complex 4-wheel steering system

– prepare the left-side and right-side hubs; install the four hubs to the two differential-motor blocks,
– prepare the yellow shock-absorber; install the shock-absorber to the two differential-motor blocks,
– install the two differential-motor units to the chassis
– install the four + four dark yellow shock absorbers

With the huge wheels installed, the chassis is ready and waiting only to receive the body in marriage.

Body restoration

The image on the left shows the body, windscreen + side windows and chrome body parts. On the right is highlighted the inside of the body where it reads from top to bottom ‘TAMIYA’, ‘RCC Bullhead’, ‘1990 Tamiya’ and ‘Made in Japan’. Investigators are wont to say; a clue is a clue, two clues are a chance and three clues are proof. On the chassis there is the year 1987 complete with the inscription made in Japan typical of the 1990s model, on the body there is the inscription 1990 complete with the inscription made in Japan typical of the 1990s model, there is the mechanical speed regulator absent from the 58535 model and there is the chrome C2 part to install the servo that moves the mechanical speed regulator… in this case there are four clues and with a certain degree of certainty we can say that the model bought is from the 1990s and not a 2012 re-release.

The following sequence of pictures shows the procedure for preparing the body for painting
– remove all stickers. Once the stickers have been removed, one immediately realises the difference in colour between the body covered by the stickers and the uncovered body. The colour is very different and this opens up new hypotheses: the model seems to have been exposed to sunlight for a long time and this has definitely changed the blue tone of the body. The question now arises whether this model has not spent most of its life on display on some shelf. The chassis has no scratches, the gears are new with no worn parts, the tyres are in excellent condition, the rims are undamaged…
– some parts of the body suggest that the model was used and tipped over. Some parts that were exposed in the event of a rollover are scratched; before priming, work these parts with 1,000 or 1,200 grit sandpaper. The scratches are really limited, but completely work the surface around the damaged parts to avoid any residual marks being visible

-wipe the surface with alcohol to remove any glue residue from the stickers and then clean the body with water and kitchen soap to degrease every part
– fill a 5-litre container with 90% pure denatured ethyl alcohol or more free of aromas or pink dyes; 99% pure alcohol is commercially available
– soak the front of the body in the 5-litre container for 12 hours. Alcohol flakes off the paint, which becomes soft and peels off, beware that as alcohol evaporates the paint becomes hard again and sticks well to the surface,
– remove the body and mechanically remove the paint using paper towels. Use suitable skin protection (disposable gloves) and eye protection (goggles),
– use cotton wool and toothpicks for hard-to-reach parts,
– it is not necessary to repeat this operation until the snout is completely free of paint, simply remove the damaged layer of paint. The body is made of styrene, the original layer of paint does not have to be completely removed, if it is not ruined simply cover it with primer and then apply the paint and
– use the same procedure with the rear part of the body.
– apply fine white primer and then

– applying paint to the body is easy because there are no parts to mask, apply TS19 ‘metallic blue’ to the entire body.

– Now all that remains is to apply the stickers.

The body is enriched with plated plastic parts such as front lights, side filters, side engine exhausts, tanks, roll bar and front engine grille, plus there is dark transparent plastic glass. On the front, complete with the black part that is the windscreen rubber

Restored model

Images showing the finished model.

Tamiya, original figure, box art, guide book and catalogue are of TAMIYA INC, which does not endose or sponsor www.tamiyaclassic.com. Any brands, logos and trademarks represented on this website are the copyright of their respective owners.