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Building the Nissan R91CP By: Eric Paley

Having been lucky enough to had the opportunity to be around Nissan Corporate US headquarters as a child, I've always had a fascination and love for both Nissan racecars, and racing itself. When I was young, I always wanted this particular RC model, but never had the chance to have one. The re-release of this kit made me very excited and most definitely prompted the overview and build of it.

This is Tamiya's re-release of the beautiful Nissan R91CP, originally released in the early 1990's. This replica takes us back to 1992 where with this car, Nissan was the very first Japanese car manufacturer to win the prestigious Daytona 24 Hours race at Daytona International Speedway.

This special Group-C chassis was offered with quite a few bodies. Amongst the few that were re-released are the stunning Mazda 787b, the Jaguar XJR-12 and the Mercedes Benz C11.

Time to dig into the box and see what we've got!

A detailed interior and driver figure.

Unlike the typically included silver-can motor, this kit includes the black-can, RS-540 Sport Tuned Motor... Nice!

Now lets get started! These, for the most part, are the tools that I use... and they tend to get me by.

Step #1

This step involves the assembly and painting of the wheels and tire mounting. I started by trying to hand brush the silver lip of the wheel... only to realize this didn't work very well, so I quickly abandoned this method, cleaned the paint off and moved to the next step.

I will tackle the wheels when the body is done. This is where I was when I stopped:

Step #2 Setting up Electronics

What will be used to power this car is a Tamiya TEU-104BK electronic speed controller, a Futaba S3004 servo, and a Futaba 2.4 radio system.

Centering the servo is key prior to installing it in the vehicle. All electronics will be plugged into each other, and with all trims on the radio system centered, when powered up, the servo will be in its center point. At this point the servo saver can be installed.

I'll be upgrading this car using the Hi-Torque servo saver, item 51000 (A white version is also available).

What you'll notice is that this servo saver is spring loaded, as compared to the single plastic stock part denoted *P4 in the instruction manual. These springs make the servo tighter, and much more effective. It also works well for high torque applications such as off-road vehicles.

UPGRADES!!

Before I get into the build, I was able to find quite a few old-school Tamiya titanium screws lying around. My thought was, old school car, old school parts! Titanium screws are much lighter than the standard steel screws. You'll notice my plate of stock steel screws on the left, and a plate of titanium screws on the right.

You also might be asking yourself, "Old screw screws. What is he talking about?!" Back in the olden days, titanium screws looked exactly like stock screws, just a different color. They had large pitched threads and Phillips heads. The drawback with these were that since titanium is much softer than steel, this sometimes made these difficult the install without damaging the head with the screwdriver. The "new" screws have tight pitch treading and an Allen head. Compare.

Step #3 Steering Servo

Servo mounts are attached and the steering tie-rods are built to length. Notice Tamiya provides 1:1 drawings of the correct lengths of the tie-rods

Steps #4 - 6 Front suspension

Step 4 involves the assembly of the uprights. It's a good idea to have a Vernier Caliper handy since the vertical shaft needs to be installed in a certain place. Luckily since the top and bottom measurement is the same, mathematically it's a one-shot deal.

Applying a drop of silicon oil to the threads of a screw really eases the tap process when screwing into new plastic.

Front suspension components were pretty simple in step 5.

Trick: When installing this to the chassis, loosen the bottom screws on the outside to relieve any twisting in the upper/lower pieces.

Steps #7 - 8 Installing Servo

Servo in place.

I noticed that in addition to the tie-rod adjustment, the chassis was slotted on both sides to the servo could be moved left and right.

Front section mounted to main bathtub chassis.

Step #9 T-Bar

The T-Bar pivots on 2 screws with an o-ring bushing. Loosening or tightening these screws changes the characteristic of the T-Bar's roll, and thus changing the handling of the car.

Step #10 - 11 Motor Box

Building the box needs to be done on a hard, flat surface to ensure it doesn't tweak when screwed together. This plastic is pretty hard, so I used oil on all of the screws.

Risers to raise the motor box. Rear wing mount.

Step #12 - 13 Rear Axle and Motor

Rear Axles and wheel hubs. Axle ends should not allow the shaft to move left and right, but also should be free enough to not bind so the shaft spin freely.

In the top right of step, it's important to screw the 3mm screws in pretty tight before you remove them. The insert has a groove, which needs to dig really well into the plastic so it doesn't fall out. Installing the motor is self-explanatory.

Step #14 Ball differential

Stock plastic parts on left, upgrades on right. Plastic 1280 bushings are being replaced with ball bearing, and the standard 0.6 spur gear is being replaced with the Hop-Up 0.4 gear pitch.

Grease the housings, insert diff rings and grease the dry sides. Press ball bearing in the inside of the longer side.

Press in diff balls, grease topside, press bearing in the underside and grease the underside as well.

Stack pieces per instructions and press bearing in the top.

Slide differential over the diff shaft.

The instruction shows building a thrust bearing, but I found that Tamiya included a preassembled thrust bearing. Drop those guys in and tighten the nut. Remember to orient the tapered washers correctly.

Tighten until it's just tight enough to not spin the spur gear with both axles held.

Step #15 Attaching Pinion Gear

Take a bird's eye view so you can put the pinion gear in line with the spur gear. Slide motor over so the gear mesh has just a little play in it.

Steps #16 - 19 Rear Damper and Installation

It is a good idea to apply some silicon oil to the thread and piston shaft before pressing it through the shock body. This ensures the o-rings don't get damaged due to dry friction.

Bleeding out air bubbles.

I made a handy-dandy shock stand out of a rear wheel and the stock spur gear. Removing air bubbles can take a while if you don't have a speed bleeder.

Press the bladder in and wipe away excess oil, then add the cap.

Check out the optional damper; item 53901... but I'm sticking old school. Might build a classic gold aluminum shock in the future.

Installing rear shock and mount.

Chassis Complete!

Now time for installing the electronics.

Steps #20 - 21 R/C Unit Installation

Placement of TEU-104BK speed controller and receiver.

Wires cleaned up and zip-tied.

Steps #22 - 23 Rear Wing. Body Post

Kit includes 2 sets of stands. One is specific to this Nissan kit.

Mount held in with 2 bolts and 2 nuts. Keep in mind to loosen the top screws slightly to relieve any unwanted tweak.

Rear body posts. I used toothpicks to show the orientation of the body-pin holes.

Step #24 Attaching Wheels...

Since I didn't complete the wheels, I wont attach them yet. However, the kit comes with four 1150 metal bearings for the wheels. I will be replacing them with four 1150 sealed ball bearings.

And there you have it!!

A completed Tamiya Group-C Chassis kit.

Body? Paint? Stickers? Coming soon...

And now onto the body and wheels for the R91CP!

In this segment, I will document the steps for completing the body, wing, and accessories to highlight the detailed realism that Tamiya is known for. Along the way, I will provide helpful hints and pointers for sections that may be more challenging to the average modeler... When all is said and done, my goal is to create confidence in yourselves to paint and detail an R/C body. whatever it may be, and provide information to help with ease and putting your thoughts down on paper, or in this case clear molded lexan.

Let's get started. Making sure you have the basics for doing a body is important. Refer to the instruction manual for suggested paints and materials. If you're doing a custom paint scheme, then pick paints accordingly. In this case, I'm using the standard blue, red and white for the body. I'll be using other paints for the wheels and interior, which I'll outline later.

In this kit, it includes a clear body, wing and light buckets, molded interior and driver head, and stickers... that's it! If you are familiar with Tamiya kits, in most cases, they provide a window-masking sheet that has the windows traced out. This makes masking off the windows easy. In this case, I will have to mask off the window, and the headlight sections for the light buckets myself.

Lets get started with the wheels. You'll notice that I'm using paint PS-48. PS colors are actually designed to be used on the clear, polycarbonate shells. Although the PS colors will typically have a dull finish, they do in fact stick to hard plastic; plus you can always put a TS-13 Gloss Clear on top of it. The interesting thing about PS-48 is, when you apply three of four coats inside a lexan body, it will appear to not lie on heavy, or have a "deep" finish. However, when you apply black behind it, that is when the paint color "pops". It will have an almost chrome-like finish, thus adding it on top of black plastic should create a similar effect.

Masking the flat edge of the wheels. Since this car uses foam tires, they are actually taped on with a very thin, clear double-sided tape. Having this area painted will not allow the tape to stick very well. Additionally, I left just a little of the edge showing so the "lip" of the wheel will be finished.

Off to painting!

Once the paint completely cures, I can apply the clear to make the wheel lip shine! Then I can paint the center-spoke section and detail the rivets.

Moving forward, at least I thought. So I was going through the kit today to get back on it, and look what I found!! I guess I hadn't fully finished the chroming aspect of the wheels.

and... Done!

Time to get out the paint and paint brushes. Since I painted the wheel chrome, I have to paint the spoke parts black.

It was kind of a rough start. Using the flat black gave it a rough texture, but once I paint the outer wheel bolts, and apply a clear coat, it should look pretty good.

Well, they're all done for now. Once dried, the outer wheel bolts will be painted silver or gold, then clear coat. An SSR sticker is to be applied to a spoke, and then they're ready for the foam tires!

With a fine tip paintbrush, lets get those rivets painted.

All done, and ready for a clear coat...

Clear coat done... They're now ready for the foam tires.

Now that the wheels are done painting, lets remove the masking tape and start the foam installation. The foam tires just slip over the flat surface, however, there is a thin, clear double-sided tape that is used to secure the foam to the plastic wheel.

Lets start with the front wheels.

the same application goes for the rear. You'll notice the rear wheels use the wider tape.

The following picture is a fix for the front wheels. The foam tire is evidently not as wide as the wheel, so I had to peel the inner tape up, and apply it closer to the center of the wheel.

Foam tires.

You start by pulling back the double-sided tape in one direction and folding them to the outside and inside of the rim. Carefully pull the tire over the open tape section and slide the rest of the tire over the wheel until it's completely onto the wheel and straight.

On the face side, as well as the backside, flick the sidewall up so it seats itself to the edge of the wheel. The tape that is exposed can catch the foam and cause the tire not to sit straight.

Now in the directing the tape was folded, you'll want to carefully pull the clear tape film out. Keep in mind this tape can easily tear if it snags on the tire or wheel. The first picture shows the tape folding and catching the tire. The second picture shows the correct look, and direction to pull the tape. It's important to keep the foam straight during this process.

When you get to the 360-degree mark, carefully pull the last section out. This is where the tape will tear the easiest because if you keep pulling at the same angle, it will catch on the starting point of the tape. This is where you want to pull it out perpendicular to the edge.

The same procedure goes for the rear.

Tires: Done.

Now that the wheels are done, lets take a look at the body and interior. The following shows the body and interior procedures.

Lets gather what I need to start the interior. We've got some Fine Surface Primer to apply first, then some TS-29 (semi-gloss black) to do the main areas of the interior.

Here's a shot of the interior primered. Obviously you don't really notice the paint since it's white. Adding even coats of primer really helps with preparing the painting surface.

Once the primer has cured, lets start spraying the black. This is done with a few coats until the black is fully filled in. The semi-gloss looks good once the surface has cured.

It's important to let the black paint fully cure before apply addition coats and detail work to the driver figure. This is a good time to start prepping the body for paint. The first thing you should do with the polycarbonate body is wash it with warm soap and water. This removes anything that may be on the surface, as well as any release agents that are still on the plastic from the mold process.

A few things I'll use for this body are pinstriped tape, masking tape, and blue painters tape.

Since this is a re-release, some things are done the same and some are done a little differently. Unfortunately, unlike most current Tamiya bodies, this one did not come with pre-outlined window mask, therefore I'll have to mask the windows myself. It isn't incredibly difficult, but more time consuming. A difference from the original is the fact that the re-release body was molded with the polycarbonate plastic that has the protective film on it, as compared to the original. This is definitely a plus.

First, ill start with the front window and use pinstriped tape to mask the outline of the window.

With the Tamiya masking tape, just tape up the window.

The same outline and masking technique goes for the side window as well. Once this is all done, then it's time to start masking the painted areas.

... I almost forgot, the headlight area is clear, so I needed to mask that off first. They were much more of a pain since they're in a tight spot to mask.

The driver figure helmet comes on it's own little parts tree. It also includes the steering wheel and shifter. I removed the two helmet halves and base and used Tamiya Thin Cement between the pieces when putting them together, in addition to the screw. Once together, I ran a long screw in the bottom and used a vice-grip as a holder. Using TS-26 Pure White, I sprayed the complete helmet and set it aside to dry.

Onto the interior; I pulled out what I will be using for the interior. The driver figure's suit and gloves will be flat red XF-7. Since I painted the interior black, I'm going to use the pink on highlighted areas to let the brightness of the red stand out in certain areas.

Starting to paint the first coat of flat red on the suit

Suit completed!

I'm not much of a plastic modeler, so I didn't do an incredible job, but I went in and painted the belt buckles, locking mechanism, steering column, and some crease lines in the suit.

Onto the body! Masking the body isn't too difficult, but I cant say it's easy either. It does take practice to master doing things correctly and in the right order. This body is Blue, Red, and White. Because we are painting the body from the inside, you paint dark colors first, then lights. I will be masking the white areas off first, then red before spraying the blue.
If you look closely between the headlights on the hood, Tamiya actually scribed the line in which to separate the blue and white colors. There is also a scribe line for the separation of white and red.

I use pinstripe tape along the scribe line to make a nice edge between the white and the blue and red.

Using blue painters tape, the white area is masked.

Once the white area is masked off, I quickly masked off the red area with yellow masking tape. I'll tend to use different color masking take for different areas if I can to differentiate the areas.

The body is now ready to paint!

Using PS-4 Blue, start by spraying a few light coats and letting it dry for a few minutes. Continue spraying a few light coats and possible one slightly heavier coat to finish it off.

The wing is also going to be painted red and blue, so I masked the red area off and secured it to a flat piece of cardboard, along with the wing side pieces. These areas were then sprayed with the same PS-4 Blue.

Once the paint has dried, start removing the masking tape to paint the red.

Paint the red like the blue. Start with a few light coats, and go from there.

Remove all the masking and pinstriping tape to paint the white.

Paint the white. And the main colors are now painted.

I then did some of the other pieces. Painted the red on the wing, and back the side pieces with white.

Once that dried, I backed the wing with white.

Since I'll be putting a "blacked� interior inside the body, it is guaranteed to show through the white paint. A remedy for this is to back white paint with silver.

After the paint dried, I decided to add a little texture to the "interior roof" of the body. I misted in some black paint to make a speckled look. While outside, I also painted the backsides of the wing and side pieces.

Instead of painting the underside of the headlight bucket, I decided to paint the face side. This will also show texture in the paint. In doing so, I first needed to remove the protective layer, since that is the side I'll be painting.

A few light coats to start.

Finished it off, as well as backed the wing and side pieces black

While all this paint is drying, lets get working on finishing the interior and helmet. I started my using an X-acto knife to cut the stickers out on the sticker sheet. The interior stickers consisted of a large and small gauge cluster, as well as two, Sabelt seatbelt stickers.

Applying of the Sabelt stickers, as well as the finished product.

Once the helmet has dried, its time to start detailing it. I started by painting the skin section with a flat finish. I avoided the eye whites, and the molded "head-sock" areas.

I then used flat black to paint the area around the face, as well as the bottom circumference of the helmet. I also dotted the eyes and did eyebrows.

Now that the helmet detail is done, it's time to apply the livery. The following shows the helmet which ill be doing.

Its important to apply the sticker as straight as possible. The left and right sides need to line up. Once the sticker is applied, use a heat gun to soften the sticker so it molds itself around the curved surface of the helmet.

The top sticker is probably the most difficult of them all. Its cutout is intended to make a solid round spot of the top of the helmet. I started by centering the front as best as possible and worked one side into place, then the other, ever so slightly overlapping them in the center. You'll notice that the curved helmet causes the sticker not to lie nicely against the surface.

Heating the sticker with the heat gun really helps to lay stickers flat, as you see. It's time to put the last sticker on the helmet.

Center this sticker directly at the back of the helmet and work each side forward using the bottom black edge as a guide.

Now the helmet is done. It's ready to install on the figure's body.

You simply use plastic side cutters to remove the area where the helmet mounts

The instruction manual doesn't call for this, but I added a 3mm washer to the screw to help it sit flat on the underside of the interior.

Put the helmet in place and screw it in!

Its now time to apply stickers to the body. Let get the window mask off and get started.

I like to do sections of the body at a time, so lets start with the front. Before applying stickers, don't forget to peel up the protective film.

Lets start by applying some of the grill stickers and the headlight surrounds. The surround sticker, since thin, can curve easily, so apply making sure they line up nicely on the mold line.

Some Nissan insignia and the famous #23

You'll notice with this sticker, I cut from left to right. This leaves some clear areas that sometime look tacky. I like to apply these stickers as one piece because it ensures the spacing between the three logos is correct. I use an X-acto and light trim at the clear part, peel it up and remove it.

Looks like the front is pretty much done, and it's time to work on the sides.

Lets peel up the protective film and start applying stickers per instruction manual. The left side is pretty much identical to right side, so I'll showcase the application of just the left side.

The exhaust shield sticker has a clear center, which goes over and indented area of the body. I cut this out with an X-acto. This made for applying the exhaust pipe sticker easier. Heated it up and if molded itself nicely in the spot.

A quick look at the almost completed side.

Lets start the windows. These surrounds aren't too difficult, but it's important to put this windshield banner on straight so the other ones line up to it.

Side windows consist of two stickers each, which sit right where they need to.

Add a few last details to the sides and rear, and we're done with the body stickering.

Now that the main body is stickers, it's time to move on to miscellaneous items, such as the wing, rear intake, side mirror. Etc. The following images will showcase these pieces. Wing - after peeling the protective film off, I applied the large Nissan sticker. As tackled earlier, this large sticker shows lots of clear areas. Luckily the Nissan logo is mostly straight lines, so I cut the clear and peeled it out.

There are two stickers per headlight. Put them in place and heated them to flatten the edges.

SSR logo on the wheels

Building the rear intake was like the helmet. It consists of two halves and a base. I glued these together with Tamiya Thin Cement and then screwed it together. Tamiya gives a little round, black sticker to cover over the hole to make it 'almost' disappear.

The side mirror has an insert, which I glued in place before applying the sticker.

Now that all of the body accessories have been completed it's now time to get things cut out, and parts installed onto the body.

I first started with getting the chassis done. First step: get the wheels on. The rear wheels are held on by two 3x10mm machine screws.

The spoke section is held on be one 3x10mm tapping screw.

Lets get the ball bearings off the axle and pressed into the front wheels. The wheels roll on this bearing on a fixed, non-rotating axle

Now to the fun part! Have you ever cut a body out using scissors, even curved scissors, and still been dissatisfied with the jagged outcome? Well, I'm going to show a method that is used by many, but also a method that isn't commonly known.
First, you start by taking a sharp X-acto knife and very carefully score the body right along the trim line. Keep in mind that what you score is how it will come out, so try and make each straight area straight, and every arc as nice as possible... Try not to slip the knife as well.

What I do is on the left and right side, try folding the bottom of the body right at the score until it cracks right along the line. What you'll see in the next few images is an interesting characteristic of polycarbonate plastic.... Where there is a score line, the plastic will crack and tear right along that score line.

Body has been nicely scored and cut out... the excess plastic, which will now go into the trash.

Headlight buckets, interior and rear wing, - ready to install

Now that the headlight buckets are cut out. It's time to install them. They are held in by two, 2mm screws secured by a nut. One of the screws is at the top of the bucket, and the other one is at the bottom towards the outside of the vehicle.

The side of the rear wing as also bolted to the main wing by two screws and nuts. Typically I drill the holes using a body reemer, but in this case, I didn't have one, so I used an X-acto knife since the holes are small. The actual side-pieces were pre-drilled by Tamiya.

Assembled Rear Wing

Installation of the front windshield wiper is also a breeze. The hole in the body is already predrilled, and all that it takes is pressing the piece through the body and securing it with an o-ring and body pin.

With the freshly cut out interior, it's time to install it into the body. The instructions shows the placement of three Velcro strips along the outside and on the front.

Just peel the outer stick cover off and insert it into the body.

We are almost done. The wing section needs to be secured to the wing frame which is bolted directly to the chassis. Unlike many common RC bodies where the wing is attached to the body, this one is attached right to the rear bulkhead of the chassis... exactly the same as the F1 cars. The wing is attached to the frame by two screws.

A look at the body mounted on the chassis!!!.... oh wait, I still need to add the rear air intake...

It is called out in the manual to install the rear intake with two screws, however, the body didn't seem to have dimple marks for the holes to be drilled. I thought about it, and decided that instead of guessing, double-sided tape would be more that sufficient.

There we go... the R91CP at the 99% completed mark. At this point, just need to double-check all of the steps, take some nice "photo-studio" photos, and get it out on the track!!