Clock Number 3

Since Christmas, I have addressed some of the problems that beset my previous clock, particularly the escapement mechanism. JKBrickworks made this fabulous sculpture, and it has a much better escapement in it. I asked if I could steal his idea and incorporated it into my clock.

The escapement mechanism is at the back. In front of that, on the black frame, is the power mechanism and winding mechanism. The clock is powered by weights (two Lego boat weights and an old electric motor) on the end of a piece of string (also a genuine Lego part).

There is also a winding mechanism that allows one to wind up the weight again whilst the clock is working. This took quite a lot of building and rebuilding to get the geometry right. It depends on a differential gear and a ratchet. It also took a few rebuilds to get it to work smoothly. One of the challenges with a Lego clock – in fact with any clock – is that the axles can bind if the frame isn’t rigid. Any axle that needs to go through three holes is especially problematic.

At the front, in the yellow frame, is the gearing mechanism that I used in my previous clock. The only addition is a few gears to make sure that the “ticking” of the escapement (which has 12 teeth, and hence rotates in 12 ticks) corresponds with one tick of the second-hand (which needs to rotate in 60 ticks).

With the gearing ratios correct (it’s not complicated – just multiplication) making the clock keep correct time is mostly about getting the length of the pendulum right. I could have looked up the physics on how to do this properly, but I chose the trial and error method instead. I found a round weight to go on the end (thanks Han Solo) and adjusted it up and down until the timing was about right. The clock keeps correct time for as long as it takes before it runs out of string … just 2 minutes at the moment. Not fantastically practical as a clock yet (and not as long as the previous version), but I’m much happier with the results.

A note about the clock tower: this is a simple construction made of 2×2 and 2×4 bricks using the parts from last year’s wedding cake.

I’m not the first to make a working clock in Lego. Nico71 made this clock with hour, minute and second hands. Someone called Gonkius made a clock which is weight powered, (but automatically winds itself, and uses a Lego Mindstorms robotics controller to adjust the pendulum length to keep correct time). For something really different, DrDudeNL made this Congreve clock in Lego.

 

Technic Radio Controlled Car (part 2)

In January, I expressed my frustration about the lack of radio controlled car in the LEGO Technic range, or indeed about LEGO Technic cars that can be motor-powered. The latter point appears to have been addressed somewhat in the new 42050 Drag Racer. At the end of the instructions (see the Brickset listing and scroll down), steps are given for incorporating 8293 Motor Set. This makes it possible to add the small ‘M’ Motor to the drive-train, and make this beast do wheelies. The battery box sits right at the back, as a counterweight. Sadly, there appears to be no radio control option in the instructions.

So I am still on my quest for making a radio controlled car out of one of the current Lego Technic vehicles. I have a remote control and receiver, I have motors and servos, I have a battery box and cables. I even have batteries. So let’s look at some of the cars available and see if they are suitable.

First up is 42046 Getaway Racer. Fabulous styling with a pull-back-and-let-go motor. Perfect for smashing into big sister’s feet or newly painted skirting boards, or generally getting bad guys away from the scene of the crime. I built this using parts I already had, hence the slightly different colour scheme from the official version, and the lack of stickers. I love this little rascal.

42046 Getaway Racer

This Technic model is at the lower end of the price range. It is easy to build, targeted at the lower end of the age range, and should present no major problems to new or experienced Technic builders. It’s also great fun to play with.

42046 Getaway Racer

So how does it fare for radio control? I would love to make this model skid round the room but alas it doesn’t have working steering, and it isn’t big enough for the parts we need to add. The Lego Power Functions battery box (with the orange switch in the picture below) is nearly as big as the racer. And we also need to squeeze in the receiver (bottom right), the servo and the motor.

42046 Getaway Racer and radio control parts

 

So the little getaway racer has got away without radio control today. Shame really, cos I really like that car. Next time, we will look at something slightly bigger.

* Note on Links – Many links on this page point to Brickset.com instead of shop.lego.com. Although I would like to point you directly to the shopping page, the correct web address depends on what country you are shopping from, and might not work. So I point you at Brickset instead. Brickset has links to the Lego shopping pages in different countries, as well as loads of other useful information about the LEGO sets, going right back to the dawn of time.