Tag Archives: Sol Expert

Making a 4mm Radio Control Truck Pt6

The Easter holiday was very productive as I have managed to get my radio control pick-up truck working. Here is a video of its first test run:

There was a few challenges. The first was trying to get the radio controller to communicate with the pick-up truck. The next challenge was a cog slipping in the servo. I also rebuilt the steering pivot as it kept slipping off at full lock.

All the electronics are hidden underneath the blue tarpaulin (which is made of tissue and PVA glue).

The charge seems to last quite some time. It also charges back up in about 15-20 minutes.

I am very pleased with this little pick-up truck and I am looking forward to building another one. Maybe I will build something for the brewery next time around.

2014-04-22 20.59.57LR

2014-04-22 21.00.24PSLR


Making a 4mm Radio Control Truck Pt5

There has been a lengthy delay in progress on my 1/76 scale radio control track (due to the house move), but the German video I posted a few days ago gave me the enthusiasm to continue.

Today I wired up the the truck and linked it up to the radio controller for the first time.

It is only going backwards and forward at the moment. I am yet to link up the steering servo to the front axle.





Making a 4mm Radio Control Truck Pt5


I did some tests with the truck on mains power and found that there could be a problem with traction. I did some experiments with elastic bands wrapped around the tyres and this really increased the traction, so I have decided to have a go at making some tyres out of silicon rubber using an alginate mould. I was quite excited about this until I realised that the rubber isn’t black!!! I decided to go ahead with the moulding anyway… annoying!

2013-10-20 13.42.48LR

2013-10-20 13.52.39LR
I also tried translating the instructions using Google translate, which made me feel a bit more confident in approaching the wiring. I was very confused about which wires to solder the capacitor on to. Based on images from one of the German forums I eventually soldered the capacitor across both the black and red wires on the motor (I’m far from an electrics wiz).
Finally, I cut away some of the flooring and fitted the servo, and the on/off switch.

2013-10-20 19.42.33LR

2013-10-20 19.43.03LR

Here is a video of the cars first trial run on mains power (with no steering).

Making a 4mm Radio Control Truck Pt4

Over the weekend I commenced work on my miniature RC car.

I eventually settled on the Oxford Die-cast AEC pick-up truck, mainly because of the ground clearance beneath the chassis. The main risk of using this truck is the difference in size of the AEC trucks wheels compared to those provided with the conversion RC kit.

Wheel removal

The first job was to remove the wheels and axles from the die-cast model. I wanted to see if it was possible to use the original wheels, so I knew I had to be careful. The Oxford Die-cast wheels are held onto the axle with an abrasive tipped axle (not quite a thread, but more a cross hatching).

The axle of the AEC truck with cross hatched tip.

The axle of the AEC truck with cross hatched tip.

This meant that a bit of gradual pulling (using a pin vice and brute strength) releases the wheels. I also realised that the Oxford Die-cast tyres are made of a similar rubber to those provided in my kit, which should be great for traction.

2013-09-28 17.12.14LR

Motor positioning

2013-09-28 16.38.56LR

The next job was to provide enough space for the motor on the die-cast chassis. I cut away at the rear of the chassis with a mini drill armed with a disc cutter. After losing about five disc cutters, I managed to clear a nice space for the motor.

2013-09-29 12.59.50LR

2013-09-29 12.58.43LR

2013-09-29 12.58.55LR

I soldered a small bit of wire to the brass gearbox, which acts as a simple harness to keep the motor inside the chassis.

2013-09-29 17.54.26LR

Building the front axle

The steering axle is a lovely, simple kit. I didn’t realise that the kit is made so that the axle will move across the x, y and z axes, so I am very pleased (as I thought I would have to adapt it for up/down movement). The plastic is also very rigid, with little chance of distortion, it looks laser cut. The wheels supplied are quite small and the rear wheels are constructed to take a double tyre (which would look a bit silly on non-lorry models). In order to fit the AEC’s original wheels I replaced the kits brass axle pins and converted new ones out of the AEC axles. I didn’t want to risk widening the holes in the steering kit to take the wider AEC axles, so I milled down the AEC axles with a mini drill and a file.

To the left - newly milled axles, made out of the AEC axle. To the right - the kits original brass plunger axle.

To the left – newly milled axles, made out of the AEC axle. To the right – the kits original brass plunger axle.

The new axles fitted to the wheels

The new axles fitted to the wheels

Fitting the steering axle

2013-09-29 17.29.26LR

I decided that the steering column needed so much space beneath the body that it would be better to cut away the front of the AEC chassis and fit it directly to the cab. I also removed the mud guards, so the wheels wouldn’t collide with them.

Thoughts on progress so far

It was at this stage that I started to realise that the wheels were too far stretched out from the steering axle. This gives the impression of some monster truck adaptation, which I quite like.

Converted truck (to the right0 with widely spaced wheels.

Converted truck (to the right0 with widely spaced wheels.

The problem is that the rear axle is fixed in the motor gear box, and is nowhere near as lengthy as the front one. Thus when the back wheels go on, the final product will look a bit stupid. So my next task will be to carefully de-construct the steering axle and re-mill the front axles until they are a bit closer to the body.

I have ordered some spare axles (just in case).

Expect an update soon.

Making a 4mm Radio Control Truck Pt2

So the next stage is to try and understand what is in the box.


I recognise a few of the parts in the box from previous radio control cars I have built (granted they were far, far bigger). I recognise a servo (and it is only 1.5 x 1.5cm!!!!).





The receiver is also shockingly small. The largest thing about the pack is the radio controller, which will easily squash the car. It seems that radio control has come on since I last dabbled. This new controller sends out a signal in Ghz rather than Mhz and seems able to be ‘programmed’ to the radio control receiver. No more of that band 1-4 crystal nonsense. This sounds like a step in the right direction. It apparently also means that you do not need such long aerials on the models, which I suppose has helped push miniaturisation forward.

My immediate concern is the wheel sets. This kit is designed to convert a lorry. I didn’t realise that it is designed for a lorry with a double tyre axle on the rear wheels, this might limit what I can convert.


I have three vehicles that may become the final RC prototype. The ground clearance is really good on the pick-up truck, but the wheels that come with the pack are much smaller than it’s current tyres. They are a much better fit to the NCB lorry, but that might be more tricky to convert.




The next step is to decipher the german component list. Let’s put google-translate to the test.

Making a 4mm Radio Control Truck Pt1

This story starts with the O gauge layout ‘The End Of The Line’ and Giles work on developing a 16mm Radio Control Truck (http://www.rmweb.co.uk/community/index.php?/topic/18108-radio-controlled-road-vehicle-and-powered-gantry-crane/)

When I first saw this truck I was fascinated. Searching the net indicates that the Germans have managed to make radio control vehicles in HO (1:87), thus it should be possible to create a radio control truck in OO (1:76).

As our UK model market generally lags behind our German and American cousins, I decided that I should have a crack at this.

I have purchased a complete starter conversion kit (which arrived from Germany today) and I now need to start preparing to construct the vehicle.

The first steps will be trying to understand the German instructions (a challenge!!!!), understanding all the components, and finding a suitable OO truck for the conversion.

Watch this space!