How to Build a Radio Control Truck
The Following How to is reproduced with Kind permission of one of our Forum Members, known on the Forum as ZAHADUM ( Phil ) This is a forum dedicated to RC Truck modellers and comes highly recommended as your next stop in getting to know more about the hobby, all hyper links detailed in these article refer to subject covered on this forum... rc-trucking.co.uk
Choosing you truck
Picking your first truck is entirely down to personal choice, so its simply a matter of having a look through our Gallerys on this web site of go on to the forum rc-trucking.co.uk and have a look through the different catagories and have a look to see what takes your fancy.
European Trucks Volvo, Scania, Mercedes,MAN the choice is yours, or your choice of American Trucks King Hauler, Globeliner or Aeromax
Also try Youtube RC Trucks at Gaydon, RC Trucks at Truckfest ect ect, you get the idea.
How much will it cost
Well this is really down to personal choice and varies widely depending on what your after. When looking for your first truck remember that there are always bargains about, be they new or used, and there is no need to rush out and buy the first thing that you see, take your time and get something you really want.
There are also ways of reducing the initial costs e.g. using a Bruder lowloader trailer ( Converstion article to follow), this can very easily be made to fit the Tamiya trucks and lots of our members have lengthened, or converted these into other types of trailers. Indeed its also possible to convert the Bruder trucks and plant machinery to be radio controlled, just search the forum for “bruder” to see how useful Bruder items can be..
What will you need
As a minimum you are going to need the following for a Tamiya set-up -
1) A truck & trailer. Tamiya currently offers the American style King hauler, Knight hauler, Globeliner and Ford trucks and also the Euro style Mercedes, Volvo, Scania r470, Scania r620 and MAN trucks. The Tamiya trailers are a box, tanker, flatbed, 3 axle refer or pipe types. Other options are Carson trailers or the Bruder lowloader. Note - the Tamiya pipe trailer comes with a extra hitch, so if you want to use with more than one truck, you will need to buy or make a basic hitch)
OR
A Tamiya Merc 1850L delivery truck.
All the Tamiya kits come with very clear detailed, step by step building instructions, but if you get stuck on anything just ask and we will do our best to help. If you intend to add extras like lights/sounds/electric trailer legs etc., it is slightly easier to add these during the initial build, but the kits are designed to be dismantled at a latter date to add these options, or to customise the built truck, so don’t think that everything must be bought & built at the same time.
2) Radio control equipment, this consists of a transmitter, a receiver, and servos.
a. Channels - Transmitters can have have 2, 3, 4, 6 or more channels. Each channel controls a function on the truck e.g. channel 1 does the steering, channel 2 controls the speed and channel 3 controls the gears (The actual channel numbers used may vary depending on the make of the radio).
While it is possible to use a 2 channel radio to control these trucks you will only be able to use one gear, so you would be missing out on using the 3-speed gearbox. So as a bare minimum you need a 3 channel to get the best out of them, but in practice its best to get a 4 channel as this allows for expansion later on e.g. lights/sounds and the price difference between 3&4 channel radios is minimal.
Note – If there is any possibility of you adding an MFU (Tamiyas sound & light system) to your truck, please check that the radio you buy is 4 channel and is compatible with the MFU as not all radio sets will work.
b. Frequency - The radio will transmit on a specific frequency. In the UK the frequency bands that surface based models can use are 27MHz, 40MHz and 2.4GHz. See this site for a list of specific frequency’s - http://www.ukrcc.org/40mhz.html
It would not be recommended to use 27MHz radios with these quality trucks, as 27MHz is very prone to interference that could see your truck taking off out of control and possible getting damaged.
The 27 & 40MHz band radios use crystals to set the specific frequency to use. These crystals are user changeable and can be changed to make sure that two or more people don’t try to use the same frequency at the same time in the same place. Care needs to be taken when ordering spare crystals to make sure you get the correct type of crystal for your radio. This thread has more details on crystal viewtopic.php?f=15&t=1786
The 2.4Ghz radios do not use crystals. They find and bind to an unused frequency automatically with minimal user intervention. 2.4Ghz is also less likely to have interference than 40MHz radios.
c. Servos, these convert the signal from the radio receiver into mechanical movement to proportionally control the steering and allow the mechanical gear-change etc.
Some radio systems used by members include the Acoms Techniplus 4 40MHz and the Planet T5 2.4GHz, both these are compatible with the Tamiya MFU.
Most radio sets will include a small 4 AA battery holder to power the radio receiver. This is not normally required as most speed controllers now have a built in BEC (battery eliminator circuit) this allows the radio receiver to be powered from the main truck battery via the speed controller.
3) Electronic Speed Controller (ESC), this proportionally controls the speed that your truck travels at, depending on the type used it may also have a reverse, brake functions.
The Tamiya TEU-101BK ESC is a popular choice for the 1/14 trucks. It is very simple to set-up & uses a nice double tap type stick movement on the radio to go into reverse. i.e. move the transmitter throttle stick forward for forward movement by the truck, 1st backward stick movement brakes the truck, and 2nd backward movement reverses the truck. This ESC can also handle upgraded motors if needed. Note – If you are using the Tamiya MFU a separate ESC is not required.
4) Motor, a 27turn motor (it is common to describe motors by how many turns of wire it has internally), is included as standard in a Tamiya truck kit. This motor is standard across the whole range of Tamiya cars, monster trunks & 1/14 trucks and it is sometimes referred to as a standard silvercan motor. Some members do use a higher turn motor instead, to get a more realistic speed for the truck. For more info on upgrading the motor see here viewtopic.php?f=33&t=1841
5) Battery’s & Chargers, the truck uses 7.2Volt 6 cell Ni-cad or NiMH stick packs. Don’t think anybody is using LiPo in the 1/14 trucks yet, but might be wrong.
A battery’s capacity is measured in mAh (milliamp per hour) so a 3000mAh has double the capacity of a 1500mAh battery.
Ni-cad are quite old technology now, the problems with Ni-cads was they could lose their capacity over time due to the “memory” effect and they would self discharge if not used for a while. For more info on this old technology, google is your friend.
NiMH battery’s have far greater capacity than Ni-cad, commonly used NiMH sizes are around 2000-5000mAH. I find two 3000mAH batts will give me a full days running of my truck.
The radio transmitter might need AA type battery’s. It will soon get expensive using normal alkaline batteries, so getting some NiMH AA batts for the transmitter would be cheaper in the long run.
A good quality battery charger is always a good investment as a poor battery charger can ruin good battery’s. For advice on battery chargers, please ask on the forums, as improvements/new features are always being made to chargers.
Depending on the charger you buy, it may be able to charge different types of battery and at different charge rates. It is very important to use the correct charge settings for the type of battery being charged. If you are not sure about how to charge your batteries, please ask on the forum and we will do our best to help.
We hope you found this guide useful. The next guide covers building & basic upgrades for your truck and can be found here viewtopic.php?f=33&t=1841
Basic upgrades & changes
These are some of the common upgrades that can be considered when building or rebuilding a truck.
1) Motor (Best done during build) – If you want to achieve a more scale speed from your truck, one of the simplest & cheapest ways is to upgrade to a higher turn motor (the higher the turns, the slower the truck will be). Common motors used are the Novak 55 turn & the Carson truck puller, the Carson motor is usually available from forum members rd trucking & lee172.
2) Bearings (Best done during build) – The truck kit comes with brass & plastic bush bearings. Upgrading theses to ball bearings is an excellent option. This will help make the truck run smoother, quieter and extend the battery run times.
When installing the metal bearings it is worthwhile checking the gearbox operation. If you find that 2nd gear wont engage properly/consistently, you should find changing the two bearings in part J7 back to the original bearings should help.
RC Trucking members will receive a 10% discount on bearings bought from http://www.rcbearings.co.uk (Contact an admin or global moderator for code)
3) Servo horns (Any-time) – The steering horn in the truck kit has a built in servo saver but if running at scale speed, the steering response can be improved by using the + horn that comes with the radio set. Just cut off 3 of the arms before fitting it. The adjustable gear change horn in the kit is usually OK, but depending on the servo used, you may find that you need more travel to fully engage 1st or 3rd. If this is the case, again just use a + horn from the radio kit and cut off 3 of the arms.
4) Servos (Best done during dual drive trucks, any time on single drive) – To get more powerful steering response, the steering servo can be upgraded to a metal geared one.
5) Euro truck steering (Best done during build) – If you want to improve the turning circle of these trucks, the steering can be increased by using the Carson steering rod. More info here viewtopic.php?f=14&t=410 The rod is usually available from forum member rd trucking.
6) Weighting tyres (Any time) – If you find that you need more weight to increase the trucks traction, you can see some ideas on what to use to weight the tyres here viewtopic.php?f=14&t=194&hilit=weighting&start=10
7) Radio stick shift gate (ASAP) – If your radio set does not come with a throttle/gear change shift gate, its highly recommend that you do get one, as this helps to avoid gear crunching and damage to the gearbox. E.g. http://www.fusionhobbies.com/ProductDet ... 88&click=2 Note - the steering/electric leg shift gate comes as part of the trailer leg kit.
Items required
Tamiya kits do not require many tools for a standard build, all you really need is -
1) Set of decent small screwdrivers with handles you can grip properly
2) Long nose pliers
3) Side cutters (preferable flush cut)
4) Scissors
5) Tweezers (to help add the stickers)
6) Knife
7) Glue (Super glue is OK, but it can turn parts white as it cures, so modelling glue is better)
Instant cement (If glueing tyres on, see below)9) Small socket drivers (optional as kit comes with wrench)
10) Small hex tools (optional as kit does come with hex tool, but a decent handled one is advised)
11) Thread lock (Small tube might be supplied in kit) Be careful what you use, see here viewtopic.php?f=14&t=421&hilit=+thread+lock
12) Grease (Small tube might be supplied in kit)
13) Selection of pots to store screws etc. during build (Preferable with lids)
14) Paint (Both primer & colour) Both Tamiya & Halfords spray paints are popular choices with lots of members, but you could use other paint. Just be absolutely certain that the paint you use is suitable for the tamiya plastic as some paints can damage the tamiya parts.
Try to select a clean tidy area for the build, you don’t want to have to spend hours searching for the tiny grub screw that got dropped or the spring/cir-clip that flew off somewhere.
Always remember its not a race, so take your time and enjoy the build.
Building your truck
You will need the truck kit, the radio system, the motor, the speed controller (Electronic Speed Control) and a charged battery to build your truck.
If you are adding options like the MFU (sounds&lights) or electric legs for the trailer, it is slightly easier to add them when building the truck BUT it is not essential, the kits are designed to dismantle easily to allow these to be added at any time you want.
Unpack the truck kit and use the rear pages of the tamiya manual to check that all the trees (the plastic mouldings that you will cut your plastic parts from) and screw bags etc. are all present and correct. Tamiyas quality control is excellent but its still worth checking for any missing / mis-molded parts.
Do please take the time to read the Tamiya manuals thoroughly before starting your build, especially if adding options at the same time as the truck and option kit builds do interact and its important to understand how the kits fit together
Unpack the radio system and speed controller and check its all present. The radio system will probable come with a 4AA battery holder that the radio instructions say powers the radio receiver, this is not normally required as most speed controllers will power the radio receiver instead.
It is advisable to connect up the radio receiver, servos, speed controller, motor and charged battery to check they all work before mounting in the truck. This should be straight forward, just follow the radio and speed controllers instructions, if you need any help, just ask on the forum.
If the speed controller has a on/off switch, the radio transmitter should always be turned on before the speed controller and off after the speed controller. You may notice that the receiver has more channels than the transmitter, this is common and is not a problem, as the spare receiver channels are simply not used.
Painting the Cab
To get a good paint finish on the cab, you need good preparation. Its much better to prepare fully than spend days sanding down a bad paint job. If you have never sprayed before, try using an off-cut of a plastic tree to practice on first.
1) Prepare the spraying area, use a nice clean warm area where there is plenty of ventilation, and no airborne contamination that might land on the parts between coats. A large box on its side may help as an improvised spray booth.
2) prepare the parts to be painted, its best to wash and thoroughly dry the parts before painting, even if they “look” clean, they may still have residue on them from the manufacturing process. Dependant on the parts being spray its sometimes better to leave them on the tree while spraying.
3) Prepare the paint, spray paint works better if warm, so stand the cans in a bowl of warm water before use. Read the instructions on the tins and follow them, otherwise you may find that there are disastrous results between the primer/colour.
4) Rattle, rattle and rattle again. Make sure the spray cans are well mixed after they are warm.
5) Multiple light coats are much better than a couple of heavy ones
6) Make a note somewhere of which type of paint you used, this should make it easier to find something to remove it in the future, if you ever want to change the cab colour.
Assembling the truck
The building of the truck should be reasonably straight forward, just follow the tamiya instructions and take your time.
If you will be using the MFU vibration feature it is advisable to use a little thread-lock on all the screws on the chassis, to avoid them coming loose in use.
It is a good idea to empty each bag of screws into its own storage pot and put the bag label in there as well. Don’t be afraid to use the grease liberally.
It's worth paying particular attention to the instructions while assembling the gearbox, as this is quite complex, and double check that this is correct before mounting into chassis, as if its wrong, its quite a lot of work to remove it when the truck is finished.
When mounting the rear drive axles pay attention to the orientation of the rear axles when mounting them, as if they are upside down, the wheels will rotate in the wrong direction.
Glueing the tyres to the wheel rims – although this is in the instruction, it is not always required, it is quite possible to run trucks without glueing the tyres to the rims with no problems. Suspect its only an issue if pulling heavy loads.
Assembling the trailer
The building of the trailer should also be straight forward, just follow the tamiya instructions and take your time. Again if adding extras like the electric legs or lights its worth reading both instructions first. The trailers are also designed to allow the options to be installed later on if required.
If adding the electric trailer legs, it might be worth using a stronger return spring in the support leg crank, as sometimes the mechanical switch mechanism can become sticky over time and the legs will continually try to move.
When building the box trailer it is wise to secure the panels with a little glue or something, just to stop the panels rattling when in motion.
We hope you found the guide useful. If you have any questions, just ask on the forum, and we will do our best to help you.
Again Mega Thanks to Phil for his kind permission in the reproduction of these article.....more to follow
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