howitzer

Maybe they should not be playing with Technic, but matter of fact is that they still are. Recalling my own childhood, I did a lot of things that were hard on the parts, and while I know better now, I don't think I'm an exception. Official sets have to be usable for children.

Both have their advantages and disadvantages and you should choose the one which is more appropriate for the task at hand. Manual functions of course have the advantage of extremely accurate control. There's no way you can achieve such an accuracy with motors, unless you're going to full Mindstorms with your model. For example, smooth steering of a vehicle is almost impossible with PF only. On the other hand, some functions would be really tedious to operate with manual control, such as booms and hoists of larger cranes.

I have 7 of those bricks, and assuming 50g each, it's 350g total. Besides, I have only one battery box and I need it for the rewinding motor.

Very interesting, thank you for the video! Your heavy counterweight obviously plays a significant role, as you can fling the projectile with that much of power even with such a short dropping distance. But I want to keep it LEGO and I'm not aware of any very heavy bricks, beside the 2x6x2 black ones which I used. I wouldn't have thought that the projectile affects so much the outcome though. I guess adding wheels and trying with heavier projectile might help, but first I'm going to attempt to make a motorized rewinder. I'm not yet sure if the axles can handle enough torque but we'll have to see.

The sling ropes are currently limited by the rope selection I have available, but yeah, in principle, longer ropes would increase the throwing power. There's of course a limit to this too, as the sling has to travel longer distance to the release point with longer ropes and if they are too long, the projectile won't be released at optimal height. I don't think it affects the jumping though, as the projectile isn't really connected to the rest of the machine, so it would jump regardless of the projectile weight. Only way to make it not jump is to make the whole assembly heavier. I'm in the process of doing a complete rebuild of the base, with some modifications to the arm, with intention to add motorized rewinding and better release mechanism. It's been quite a challenging so far but we'll see.

Thanks, and hello there fellow finnish-speaking person! Putting the weight very close to the pivot reduces throwing power a lot, because the dropping distance of the weight would be shorter. There's a lot of physics involved, but in the end it's a tradeoff between throwing power and size/stability of the machine. The real problem with a trebuchet though, is scaling: the counterweight is limited by volume, and for every doubling in machine size you get eight times more volume and thus eight times more weight (using the same density materials). So larger machine will always be much more powerful than smaller one.

A tower crane. I mean, almost every other kind of a crane has been seen in an official set, yet this piece of construction equipment that's very common in real life life is conspicuously absent from the official sets.

Yeah, I thought about that, but my first thought was to put it on a turntable, so that's what I set out to build. I didn't have enough correct kinds of parts for proper turntable though, so it ended up stationary. But yeah, have to think about it. I don't think I've ever posted a video online of anything, maybe this could be first...

Hi, this is my first MOC to be posted online. I made a trebuchet, or in other words, a counterweight catapult. It's mainly built from 42055 BWE parts, with some from other sets, totaling somewhere in the neighbourhood of 1500-2000 pieces. It's fully functional in the sense that it actually fires projectiles. It was quite a satisfying to build, although there isn't really that much going on, mechanically or functionally. The firing mechanism is a simple axle that's drawn out to release the sling arm (held by two small turntables) and both firing and reloading are manual. It work's though, most of the time the "rocks" are flung at least few meters away, though accuracy is not stellar. It could probably be improved with other kind of ammunition (steel bearing balls or whatever) but I like to keep it all LEGO. This of course means that there's no way it could actually break any castle walls or anything, as bricks are much too lightweight to cause any damage. Some thoughts on possible improvements: It is a bit too lightweight, as releasing the arm causes the base to jump a bit. I don't have any more of the weighted pieces but something like them added to the base should help a lot. This is also why the base is so heavy with parts, I inserted mostly because I needed to lower the centre of gravity and make it overall heavier. The sling could be also probably better, to make more repeatable shots. Finally, the release mechanism could probably be improved too, maybe by having some gears connected to the turntables and drawing out one of them would release the arm. It could even be extended to a rewinding mechanism turned by a crank or even a motor, though it might require quite a bit of gear reduction for even an XL motor. First, no ammunition inserted, but otherwise ready to fire. Closeup of the sling, with BWE "stone" inserted. This was the most difficult part, I had to find an actual study which examined how to make a sling with capable of releasing the projectile at correct point during the firing sequence. And after firing. Hope you like it!

Hello everyone! I'm one of those people who loved LEGO as a kid, but like so many others, at some point entered the darkness and mostly forgot about the beloved bricks. Now, around last Christmas while sitting on the dinner table I got a message from a friend, telling that there's a Millennium Falcon set for sale in local retail store at absurdly low price, and I immediately ran upstairs to place an order on it. Sadly though, it happened to be a fluke in their pricing system, and they canceled my order (and my friend's order too). This left me extremely frustrated and disappointed though, as I realized I've missed the bricks a lot, so I decided to do something about it. So couple of weeks later I went up the store, and bought myself the 42055 Bucket Wheel Excavator, the first new set for myself in 25 years. Took me several evenings to build it, and I knew this was it, I was exiting the darkness. Afterwards I went online to search for mods, improvements and other info on the set, and found my way here. Now I'm considering MOCs, and contemplating on my next set investment and spending a lot of time generally reading about all things related to legos. At the moment I'm mostly interested in Technic, as it seems to offer the most interesting options for MOCs, though I might go for the Mindstorms in the future. Other than that, I'm 35 years old and live in Finland. I love handcrafting of all kinds (wood, metal, yarn, whatever) and spent years as a goldsmith, but right now I'm studying pharmacy. Some of my jewelry work can be seen at my website in http://www.jousimo.fi/ (only in finnish, sorry). Anyway, I'm glad to be here, see you in the forums!