Special Edition TCS M04
(by Michael Steele)

BUILDING A TAMIYA CHAMPIONSHIP (TCS) MINI:

In The Beginning:

In the beginning, I wanted the car to be as “trick” as possible. During a trip to Advance Hobbies, I spent some time drooling at the wall of endless Tamiya options parts to see if I could spy something that I did not have that could be used to make the car look trick - I found blue! New blue anodized ball ends, wheel hubs, heat sinks, threaded shocks and even zip ties! I decided I would try to make everything as blue as possible - including the plastic chassis.

The Chassis:

Last year I experimented with a new paint call “Fusion” by a company called Krylon. This paint is the first of its kind designed specifically to adhere to plastic and not peel or flake off. It also does not require a primer. The original intent was to use it to paint F -1 wings for the F201 chassis to match the real F-1 cars when creating an alternative livery using my own decals. Thankfully, the new decal kits available from F-1 racing.com come with pre-cut vinyl decals for the wings and I wasn’t required to paint any of the wings.

So what did I do? I painted a gearbox on the F-1 car instead. It was amazing - went on smooth, brilliant color, very hard wearing and people kept asking me “how did you do that?” (some also asked why, but I thought it looked cool…. so go away).

I started by clipping the following parts from the MO4 tree:

Rear Gearbox - A5, A6

Chassis Parts - F1, F2, F2

Battery Holder and extension - C11, C4

Front Bulkhead - A3, A4

Front and Rear Bumper Parts - C20, E2, E3

The Transmission:

When selecting a ball diff for this car you have two choices - what are the differences???

TAM 53070 - Manta Ray Ball Diff Set

Originally appearing in 1993 this diff set was designed as a HOP UP part for the off road buggy Manta Ray - this was also the buggy that the TA 01 sedan was based on. It’s thrust washer needs to be assembled from a plastic ring with holes using individual ball bearings which can be tricky but does include hardened out-drives (drive cups) which are exceptionally long wearing. This diff is generally cheaper and if built correctly will last a long time.

TAM 53267 - TA03 Ball Differential Set

Released in 1997, this unit was what the original TA 03 Pro came with when you bought the kit. It differs from the Manta Ray unit by coming with a one-piece thrust bearing assembly

I started with the building of the differential, in this case the TA03 Version (TAM 53509). I like this diff as it comes with the aftermarket hop up thrust bearing - and this little guy is the secret to having a nice smooth diff.

Start by packing this thrust bearing with Tamiya Anti Wear Grease or Associated black grease. Next, with some diff lube on the ends of your fingers, coat the back and front of the diff rings with a thin layer of lube and place on the diff hubs paying special attention as to the direction. The flat surface should be seated against the diff hub with the rounded shoulder on the outer edge of the diff ring pointing up. Place a small dab of Tamiya Thread Lock into the diff hub that is threaded and assemble as per the instructions making sure to place all of the cone washers in the correct order. Tighten fully and then back off half a turn. The diff will feel very tight, but will become smoother after a couple of runs.

Now it is time to assemble the completed transmission.
But first, my view on the age-old argument of adjusting the TA03 / Manta Ray diffs.

IMPORTANT - I have been building this style of ball diff for years ( it first appeared in its current form in the Astute / Egress off-road cars - and finally through the entire range of TA 01, 02, 03 and FF series of cars and trucks). Although it has evolved over the years it is not designed as a fully adjustable diff. Lets take a look at why.

If you look at a differential in a touring car you will see that diff adjustment is often made by a long threaded screw that passes through a thrust bearing, spring and then a small lock nut. This allows the screw to be tightened and loosened, putting more or less pressure on the spring which in turn puts more or less pressure on the diffs plates. These diffs can be adjusted from very loose to very tight - and because of the lock nut will maintain their adjustment.

Instead of a spring, the Manta Ray and TA 03 differentials use a series of cone washers ( 3 in fact ) that are clam shelled together to put pressure on the diff plates. The pressure is applied by a large nut that is screwed into the opposing diff hub, which does not contain a nylon lock nut. This is why it is very important that the diff be properly tightened and secured with a small bad of thread lock. It will work its way loose otherwise (trust me) . I have seen many people attempt to back off this screw to try to make the diff smoother or looser to affect the handling of the car - if you have done this you are most likely familiar with the sound of the motor spooling up and the diff spooling loose! I know I have heard it a few time in my own car - and it is no fun as it generally takes a few laps to completely loosen off. The other trick has been to just thread lock the diff to the right adjustment - it will stay for sure, right? If it does, then it does… but from experience it won’t, and you’ll soon be sitting down at the bench for another long trip inside your gearbox. If you still feel strongly about adjusting the diff like this then better get an electric screwdriver because you only need to crack the gearbox open at a race once to know that it is something you do not want to do after every heat!

Loosening the diff will also not correct an ill handling or tweaked car - if your diff is notchy and not smooth then rebuild it. I’ll make it easy, the parts numbers are:

TAM 53072 - Manta Ray Differential Ball and Plate Set

TAM 53136 One Piece Ball Thrust Bearing

Finally time to cram it all in the gearbox and close it up.
People often ask me why my mini is so quiet - here are a few tips. To lubricate the gears I use a product called Super Speed Gear Lube by Aero-Car Technology . This comes in a small container and is a solid orange paste. Use a small paintbrush to give the diff gear and counter gears a very, very light coating (see photo). Make sure not to just stuff a big chunk in the gears and rotate them together as this will simply fly off, coating the gearbox with useless guck that won’t help lubricate anything. Also make sure NOT to apply lube to the spur gear that the pinion will ride up against. I also used the MO3 Hollow Carbon Gear Shaft Set(TAM 53390) to mount the gears on. Close it up and screw everything together making sure everything rotates smoothly.

Building the Universals - Option Part TAM 53205

The title sounds easy enough, but a few tricks will help them last an eternity. Start by taking the dog bone end of the universal and dipping it in to Tamiya Anti Wear Grease.(TAM 53439). Dip it in just enough to get a small dab of grease on the end. Now put this in the female axle side and twirl it around to distribute the lube evenly (see photo) . Remove the dog bone end and wipe away any excess large bits of lube. Assemble as per instruction - it is very important to place a small tab of thread lock on the grub screw to keep it all secure. Place the grub screw on the end of an Allen wrench and dip it into a small pool of thread lock squeezed onto a small piece of paper (too much thread lock may dry as a lump in the universal and cause resistance or binding).

The Diff outdrives will also require lubrication especially if you are using the TA03 ball differential kit. These outdrives are softer and the dog bone pins from the universals will notch the out drive cups if left unlubricated. Use a Q-tip to wipe the inside of the drive cups with a small amount of anti-wear grease paying attention not to use too much. In all cases with the anti-wear grease the key is to use small amounts for lubrication - too much will simply attract carpet fibers or dirt and add to the wear - the exact opposite of what you are trying to achieve. As a final note - it will also be important to clean and relube the universals and outdrives often, but more on that later.

The last and most important detail to having a smooth efficient and above all quiet transmission is the pinion. Tamiya supply aluminum pinions that wear very quickly, the teeth become sharp and this is the number one reason for the loud noise of the transmission. Replace this with an aftermarket Tamiya Hardened Steel or Robinson Racing metric pinion. Install the motor at this time making sure to use the thin green motor cover - this will stop dirt or small stones from getting sucked up through the motor and into the transmission as it won’t take long for even the smallest stone or crud to make short work of all the gears and bring you to a crunching halt. As an option I added the Tamiya MO4 Aluminum Motor Heat Sink (TAM 53389).

Now it is time to put the chassis together making sure first to screw in the battery brace (part # C4 ) as this needs to be done from the inside of the chassis. The front bulkhead and gearbox were added at this time. Now for the suspension.

Hanging the Suspension

When building the arms, I installed the stabilizer supports for the MO4 Stabilizer Set (TAM 53382) as these are almost impossible to install once the arms are on the car. Even if you don’t run both stabilizers the mounts will be in place when needed.

One of the most important aspects to having a balanced and good handling car is to ensure that all of the suspension moves freely - this will be very important when we go to set the suspension up on an MIP tweak station.

I started by putting on the front and rear lower arms attaching with the TLO1 Stainless Steel Suspension Shaft Set (TAM 53301). These shafts replace the kit supplied screw pins and are very smooth using e clips at each end to hold the shaft in place. Attach the upper and lower front arms making sure that no binding is occurring by lifting the arms up and letting them drop - they should drop effortlessly. If they don’t, it may be necessary to get a small file and remove material (or paint) from around the gearbox’s arm supports or uprights until the arms move freely. At the front, I installed the upright and upper links and at the rear I substituted the standard uprights with the Tamiya Toe In Rear Upright Set (TAM 53345). These units toe in the rear wheels 2 degrees, helping with tracking on the straights and adding stability in the corners. At this time put the universals in and finish attaching the rear upper supports making sure they fall freely. Now your car is ready for the shocks!

Building the Shocks

Following the blue theme I chose Tamiya’s TRF Threaded Damper Set in Anodized Blue (TAM 49198). These units are super smooth and the threaded collars will allow me to adjust the tweak easily and accurately. I built these units using the standard 2 hole pistons in the following combination:

Front: Tamiya #900 (90wt) Clear Oil - Short Dark Blue Spring

Rear : Tamiya # 400 (40wt) Yellow Oil - Short Red Spring

I use the Tamiya Damper Oil Sets from 100 to 1000 and the New Mini Spring Sets now available in a wide range of spring rates.

Since these shocks did not have limiters inside and the MO4 does not. have droop screws I wanted to limit the up travel of the suspension to prevent the car from transferring too much weight back to front. On the front shocks I used two black O rings on the shock shaft, and on the rear I used three black O rings (see photo).

When filling the shocks with oil I made sure to build them without any rebound. What is rebound you ask? When a shock is filled with oil and the cap screwed down it creates a seal. When pushing the piston up into the shock body it meets resistance - this will push the piston back out. How full the shock is with oil will determine how far and how fast the piston will rebound back out. In order to get a properly balanced suspension it is always the goal to get the shocks to have the same amount of rebound. If one of the shocks does have more or less rebound than another it will alter the handling of the car

With the limited adjustments on the mini, I prefer not to chance this and built the shocks with less oil so that the pistons do not rebound out of the shock bodies when compressed. For springs, Tamiya now offers a complete range of special mini shock springs in a wider range of rates.

I installed the shocks using the new Blue Anodized 5mm Aluminum Ball Connector (TAM 53642) and checked to see that everything worked smoothly. - On to the steering!

To complete the front of the car I mounted a new set of Tamiya Aluminum Uprights (TAM 53523). These are super strong and will resist breaking or twisting ( I wish they came in blue). For the steering linkage I used the new 5mm aluminum ball nut screwed in from the underside of the upright. These I connected to two 3 X 32mm Titanium Turnbuckles (TAM 53527) and linked it to Tamiya’s High Torque Servo Saver Set (TAM 50473).

Electronics

For this mini I wanted to make all the wiring as short as possible and have a nice clean layout while attempting to maintain as low a center of gravity as possible. The MO4 comes with a nifty little side tray that connects to the left side (motor side) of the chassis. It was here that I placed the super small Mtroniks cube speed control (which just happens to be blue!). This unit is exceptionally tiny and has small solder tabs that allow you to attach the correct length of wire.

First off I cut longer lengths of wire than needed and soldered the battery and motor wires, routing the battery wires through a hole in the side frame of the chassis and up through the middle. These wires were cut and a Dean’s connector added just at the top edge of the chassis with a Blue Tamiya Zip Tie (TAM 53621) to hold it in place. The motor wires were then run down the left side of the chassis and soldered to the motor taking care to make the lengths are no longer than required.

The Mtroniks cube also allows you to solder on the receiver lead cut to the perfect length and ran through a smaller hole in the side of the chassis. This appeared out the other side and was plugged into the KO receiver, which I taped to the right side of the chassis just in front of the battery compartment. Placing the receiver here kept the center of gravity as low as possible and allowed the antenna to run straight back to the antenna mount without having to pass close to any power wires.

To finish off, the steering servo lead was neatly wrapped around the center chassis brace and pulled through the same hole as the speed control lead to plug snugly into the receiver. Overall, this gave the clean tidy look I was after and allowed all speed control adjustments and crystal changes to be made easily. Please see photos.

Tires and Rims

Having run an MO4 before I chose to go with the following tire and insert combinations:

FRONT:TAM 53254 60D Super Grip Radial Tires / TAM 53223 Shaped Tire Insert

REAR: TAM 53340 60D Type A Slick / Kit Supplied Foam Insert

For rims I chose the Honda S800 Wheels (TAM 50708)
I held these in place with a set of Blue Aluminum Wheel Nuts (TAM 53159)

The Mabuchi RS 540 Motor:

Another age-old argument with everyone having the secret trick! I do not personally do anything with the Mabuchi and Johnson motors, but people rarely believe me. I do make sure the bushings are oiled and the motor is clean - but that’s all …. Honestly!!!

My philosophy has always been that you need to be able to run for the entire race without crashing before a faster motor makes a huge difference. I also replace my motor with a new one when it starts to slow down. This and having good batteries seem to provide consistent proven power. The methods that I will outline will make the motor goes faster if done right - but for how long?

Water Dipping:

The oldest method of attempting to break in the brushes on the Mabuchi / Johnson motors. As these brushes are rock hard for super long life, it is necessary to find a way to seat them on the armature quickly.

Solder two leads on to the motor so the end bell (brush side) of the motor can be dipped into a small cup or bowl of water - do not entirely submerge the whole motor. Constantly check the brushes to make sure you have not gone too far - A motor can be ruined in a matter of seconds by eliminating too much brush.

With this method you are attempting to seat the brush on the comm.. Once completed be sure to lube the bushings with a light oil. WARNING: This method can make your motor into a rocket or a dud in a matter of seconds - so try it at your on risk. I have seen many a motor slowly die during a qualifier - or even worse - a main.

Conclusion:

I hope you have enjoyed reading about the building of this Super Mini - I can hardly wait to race it! If you have any questions or comments please do not hesitate to email Michael Steele at msteele@fido.ca . See you at the track!

An original creation by: Michael Steele