It’s day 4 of the build, and that can mean only one thing – starting off by taking it all apart again.  Yes, I decided that the front subframe just will not do.  So, in an effort to make the front end more realistic I decided to move the engine so that it was on top of the wheels rather than behind them.  That meant redesigning the suspension assembly again to make it wider so that the engine could sit inside.  It was a bit tedious, to be honest, but it was worth it once it was done as it looks so much better now, and hopefully it’ll be stronger too once I get the arms braced from the front side of the subframe.

The front subframe also now has a diagonal strut on each side, further strengthening it, which is no bad thing given that’s where a lot of the force is going to be taken, right over the wheels.  I’ve also widened the front subframe to give me more space between the steering shaft and the drive shaft, which has allowed for a far more compact yet satisfactory connection between engine and drive shaft.  It now runs smoothly and efficiently with only the most essential cogs in between (I want to retain a high cog ratio so that the engine spins fast even when the car is moving slowly).  Oh, and the front subframe has been significantly shortened, too.

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Perfectionist that I am, pretty much the entire car has been rebuilt this evening, apart from the engine.  Not satisfied with the imprecise and uncontrollable steering, I completely rebuilt the whole assembly from scratch using my own custom design.  The system I’d used yesterday was taken from an official Lego model, and used their official steering pieces, but the problem lay in their axle; because the ball joint was only one stud’s width away from the pivot point it meant that the mechanism accentuated any give in the gearing rather than compensating for it.  So I rebuilt it using ‘conventional’ Lego pieces to give me a ball joint 2 studs away from the pivot point.  It took some fiddling around to get it all lined up properly and get the suspension strut sitting nicely, and then some more fiddling to get it to attach to the front subframe, but we’re finally there – I have a front suspension/steering assembly that I’m happy with!

Next on my list of things to sort out was the rear axle, which just looked plain ugly.  It would do the job, and would probably be mostly hidden by the bodywork once that was figured out, but I just didn’t like the way it looked or the way it worked – it just wasn’t realistic in any way shape or form.  So that was stripped out too.

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Following the progress made on Saturday, and a good night’s sleep or two to think about it, I sat down and did some more building this evening.  Rather than trying to connect the front axle directly to the engine block and then connect that to the rest of the car, I realised it would be far stronger to build a solid front subframe and place the other components into it.  The engine is therefore now situated behind the front axle rather than almost on top of it, which if nothing else will make the profile a little more streamlined.  With that sorted out it’s actually starting to come together!

I’ve made a start on the rear of the car too, building the rear axle.  Rather than tackling the complexities of independent driven suspension at the rear I’ve gone for a live axle with movement in only one direction.  It makes it a lot simpler, though considerably less realistic – movement on one side of the car will affect the other side just as much, which isn’t ideal.  Still, at least it works.  There’s a differential in there too, and the drive shaft has been connected to the engine at the front of the car.  I wanted to have the engine spinning at a good speed when the car is moving, so I’ve geared it all up accordingly.  Unfortunately that does mean that there’s a fair amount of resistance, but I may be able to live with that.  It may be that I’ll be able to connect in an electric motor later on to drive the engine directly and have it drive the car at a manageable speed.

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Yes, I’ve got the Lego out again.  Unlike last time I have work to do during the day, so my building is restricted to free evenings, so progress is a little slower.  Still, nothing like a good challenge.  The project this time round is a vehicle of some sort, probably a sports car or similar.  The reason for the uncertainty is that the main goal is to experiment with a combination of suspension and an active drivetrain.  I experimented a while back with ways of getting a 4×4 drive system in place, but that proved too complicated given the bricks I have, so this time I’m going for the front wheels doing the steering and the rear wheels being connected to the engine, and with all four wheels having some form of suspension, albeit limited travel.

Today I started work on the front of the car, trying to get a setup capable of steering and suspension in a small space (I want to leave space for the engine in the front too).  In the end I stole an idea from another model, and used the front suspension and steering system almost straight out of the instruction booklet.  The next problem was working out how to connect that solidly to a subframe and not have it get in the way of the drivetrain.

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C is for Cars and Carriages

Now, it may appear from this post that I have nothing better to do with my time at the moment than waste countless hours sat in front of a screen twiddling knobs and tapping incessantly on keys without really achieving anything productive.  And they may be a modicum of truth in that hypothesis.  However, I can assure you that the time I have spent playing has been (for the most part) well-chosen and has not adversely interfered with the normal running of my life.  It has of course been lots of fun.

First of all, I recently acquired something I have wanted for years – a steering wheel.  No, not for my car, but for the computer.  And since all my games are now on the PS2, it had to be one that I could plug into that.  An hour or so on eBay and a handful of reviews culminated in a purchase of a Logitech Driving Force EX steering wheel, which was plugged in and tested as soon as I was able (i.e. the evening of the day it arrived – see, I didn’t skip work for this), driving my current favourite game: Gran Turismo 4.

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The last few days I have been doing a lot of thinking.  Not about philosophy, or theology, or relationships, or anything that one might ordinarily spend a lot of time thinking about.  Oh no, I’ve got to be different.  I’ve been thinking about how to create suspension systems in Lego Technic.

Some of you may remember that a while back I spent a week creating a Lego ‘Tumbler’ (from the film Batman Begins), with working suspension and steering.  That was a technical challenge, but I managed to pull it off eventually.  I even made a couple of videos of the progress.  Since then it’s sat quietly on top of the unit in the lounge, silently gathering dust and being generally forgotten.  Until recently I couldn’t bear it any longer, and just had to start thinking about the next version.  Yes, not satisfied with a Lego Tumbler that has working suspension and steering, now I want to put motors in it too.

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