Various people have done this - however most of the links seem to point to a [then defunct] blog by Martin Howard (Randomwraith) from 2004.
A more recent, and available, post on this, using newer pieces can be seen here:
LEGO Logic by Keshav Saharia
Based on a lack of gears and rack and pinion elements, Keshav decided to rebuild the logic gates using an ...
LEGO's official position on this technique was explained at Brickfest 2006. Jamie Berard, then a relatively new designer in Billund gave an excellent presentation on why certain techniques are considered "illegal" in official sets. The basics message is that building techniques should:
not stress the bricks
be suitable for the target audience of the ...
Hooray, I get to answer a question!
This is not a piece for launching missiles. It's actually part of an old steering assembly from some late 80s and 90s Technic sets.
Here's what the whole thing looks like:
And a view of the piece in question:
And an example of how it is meant to be used:
The teeth on the outside of the piece help lock it into one of ...
Tristan Lostroh did an exhaustive test of both studded beams and stud-less beams with and without connections. Here are his results:
Studless beams are better in tension than studded
Studded beams are better in transverse than studless
Studless beams are stronger in transverse with the pins on the side
Connections to other components will fail ...
This would push the pins up and down like a normal key would.
Here is the basic system. I don't have time to build to whole thing but this resolves the main problem and proves the feasibility.
The main problem was to reproduce the pins system with LEGO bricks since each pins needs to have different lengths. Early in this project, I wanted to have a '...
From principles of molding, you want a uniform part thickness throughout if possible. This facilitates plastic flow as well as dimensional stability (you want uniform shrinkage on cooling.) Removing a divot from the underside of a stud serves this purpose in a regular brick. The Technic brick with through holes would have had a large amount of solid ...
The LEGO Pick A Brick store lists them as connector pegs (or, more simply, pegs) although they are more commonly known as pins in the fan community1.
The black ones have added friction for holding things together, while the light gray and beige ones are smoother and allow pieces to rotate, for example tires or beams.
1 BrickLink, Peeron
I reproduced the problem and got the axle out using a sculpting tool (similar to an awl). It's a sharp point made of hard metal. (Soft metal will actually bend, believe me, I tried three tools.)
I inserted the point in the space left by the axle groove and pried the axle out. The point of the tool was against the axle while the body of the tool was pushing ...
The studless have SEVERAL advantages over the studded design especially when you want to include moving parts. Just the clearances between connections is important. Sariel sums it up in his book well. He says there are advantages to both systems (stud-full, for example, are more rigid) but the fact that the stud-less look more realistic and, of course, the ...
I actually managed to find the exact set while refining the question. It's set 744, released in 1980.
Here are the reasons why the research I did prior to writing the question didn't lead anywhere:
The yellow motor does not show up when searching parts on BrickLink. It's probably because on the list of set 744 parts, it has a note saying "Part colour ...
Put two plates between each layer of Technic bricks and the holes will align.
This technique was used commonly in studded Technic sets. Here's a page from the instructions for 8042 where you can see this used in several different places:
I use a Mindstorms NXT brick and an Android smartphone for my remote controlled tank. The downside is that the NXT motors are slower than the regular Power Functions motors, and connecting PF motors to the NXT brick requires additional components.
Personally, I am satisfied with NXT motors and don't bother kludging PF motors. (Yet.)
Here is a modular truck ...
The current Mindstorms sets are completely Technic orientated and use the Technic pins (i.e. [part:3673:7]) to connect to the newer Technic Beams (i.e. [part:32316:7]) as well as the original Technic Bricks (i.e. [part:3894:7])
The various different size pins and axles are the way to interchange between these.
There are a number of Lego Pneumatic sets with airtight tubes, valves and switches which could be put into use with fluids. One is 9641, Pneumatics Add-On Set.
Bear in mind that the pneumatics sets can command a much higer price than those sets with a similar number of parts, and buying individual pieces can also get expensive. Have a look at BrickLink to ...
The regular connector have simple angles which are multiples of 22.5°. #4 is 45°, #3 is 22.5° and #5 is 67.5°. That's pretty boring stuff, but there you go.
The 53.5 angle isn't as bizarre as you would think and there's a very good reason for it (and less boring to me, but YMMV).
That reason is that it forms a Pythagorean triangle, and specifically the ...
You probably could use this, which looks exactly like it's the missing part of your puzzle:
You'll be interested to know that this part has intitially been proposed by the first four fans (MUPs, for LEGO Mindstorms Users Panel) working on the very first NXT kit and regularly ran into the same problem as yours. A lot of Technic fans now name the part after ...
I usually attach it to a Technic beam, then put something to fill the hole so it can't squeeze together and come out, to give a handle.
The flexible rods tend to be a nice options for filling the hole, the older ones may be a bit better, but I've had success with other pieces that fit minifig hands.
Once you have the blue pin attached to the beam instead ...
With some Power Functions elements and a few extra pieces, it's pretty easy to turn the Rally Car into an RC car.
Here's a quick demo video of my design in action.
And here are the instructions I made for it.
Required extra pieces
First you are going to need some extra pieces:
1x - Servo Motor
1x - IR Receiver
1x - Battery Box
1x - L-...
Personally I would go with Arduino (on the car) and an Android phone as the controller (via bluetooth). There's plenty of reference on the web about mixing the two.
The main problem is interfacing with non Lego parts (motors, PCB, ...). Luckily, you can find Lego adapter parts in many Robot/Electronic sites. For example at Pololu:
In my opinion, you don't need to look further than plastic quantity, and thus cost.
Take a normal brick or plate (easier) and look inside it. You'll notice that each stud is hollow, but from below. Why? Simply because there's no need to have it full with material as it serves no purpose. It's easy to make the mould that way, it doesn't remove any ...
I think the most important aspect is a matter of geometry.
With studded beams, you're constrained by the form factor of the regular LEGO brick, which isn't a cube but a 5:5:6 cuboid. This means that every time you need to change the orientation of things, you'll have to think about how you're going to do it, and use plates and whatnot between beams. It's ...
YES! Philippe Hurbain (Philo) has put together a great and very detailed write-up on those and many other LEGO 9V electric motors.
You can find it here: LEGO 9V Technic Motors compared characteristics
Your current draw for that specific motor @ 9V is:
No load: 65mA
Loaded (3.6 N.cm): 310mA
Loaded (6.0 N.cm): 480mA
Stalled (11 N....
The largest wheels I know are these (I measured 110x63 mm, including tyres), but they are quite rare (only available in one single set):
Weels: 22969 "Wheel Technic Racing"
Tyres: 32298 "Tyre Power Puller"
The wheels itself are not that big, but if you include the tyres, they are really huge:
They would probably work really well for an RC car.
If it's your own creation, you should be able to adapt your model to fit the rack you have. One tricky problem I can see is if your construction is built as most studless models are nowadays and features uneven dimensions - which means a 7 rack is indeed easier than a 8.
You can of course build something around the old 1x4 rack place but it might get ...
Push the Technic pin in a beam hole, then insert a rod (antenna or minifig tool handle) into the hole in the pin from the other side. The rod will prevent the "lips" of the pin from closing in, therefore preventing the pin from leaving the beam. Then you can pull on anything attached to the other end of the pin.
This example below shows the removal of a pin ...
I was very intrigued by this question. So I messed around with two LEGO Technic beams, a long one and a short one. The 'pins' at the bottom of the beams are made to fit in the hole on top of the studs.
When using the studs holes instead of the normal 'in between' way, the holes on the side of the beams are offset at mid distance. This could be very ...
In the UK shop, there are currently two sets:
The Unimog U 400 [set:8110] which uses the motorised "compressor" to supply the power (as opposed to the manual sprung pump).
And the Tractor with Log Loader [set:8049] which uses the manual pump:
The other sets that look like they have piston arms (such as [set:8043]) are actually using "linear actuators", ...