Blakbird

Having just bought this set and seen these parts for the first time, I must say that my first impression is that they are Pieces Of Other Pieces. They seem so large and specialized that they remind me of Bionicle more than Technic. Maybe they will grow on me. I do appreciate the extra strength they provide, but providing strength via monolithic parts seems like cheating.

Picked up my copy and started building last night. I was so excited about the pneumatics that I started with the crane. The first thing I noticed is an error in the instructions. Step 3 of the crane instructions is missing. It goes straight from Step 2 to Step 4. Luckily, it is easy to figure out what was missed. I really enjoyed building the crane. Like allanp, I shortened some of the blue tubes so they fit better. I really like how well guided all the hoses are.

There are probably quite a few buyers (including me) from other countries who would like one of these. You might consider partnering with a local Bricklink seller who would be willing to ship them.

In the past, LEGO has often failed to release the B-model instructions on time and it has been weeks or even months later when they become available. More recently, they have been doing a better job. I am hopeful the instructions will be available Saturday. Thanks for the images and the comparison! The only thing I don't like about the look of 42043 is that I think there is far too much space between the front tires and the fenders. It looks like a lifted off-road truck. 8258 looks much more scale appropriate. Has anyone tried the soft shocks in the front instead of the yellow hard shocks?

In my experience, there is a lot of variation in the size even in a brand new set. For example, the 8002 Destroyer Droid comes with a large number of rubber bands, but even those that are supposed to be x264 are not all the same size. Thanks for your table. It is really convenient to be able to see them all in one place. For the silicone bands, it is important to remember that the color does not necessarily tell you what size it is. For example, the x37 comes in many colors.

Everything is awesome.

The original poster referred to "unique/rare parts" so I think the list I posted nicely covers both those categories. Most of the parts listed are not unique to the set, but many are very rare or hard to find. I agree the OP was exaggerating a bit, but the core thought that this is a very good parts pack for rare parts is accurate. I'm not a big fan of the word "tons" used as an adjective because it is nearly always hyperbole. According to my list above, I found at least 4 parts which are unique to this set in a particular color. 8880 is another model with plenty of rare and unique suspension parts, some of which never came in another set in any color. Obviously, most molds for new parts are made with the intention of using them on many models, but sometimes they are not for whatever reason. The pneumatic cylinder brackets, for example, were only used twice and only the first time was for a pneumatic usage. Fiber optics, micro motors, and air tanks were also very rarely used. I've heard the stories of much money the company developing some of those components to then only use them in a handful of sets.

Then you must not be looking very closely! Rare parts include: Black bushings Black pulley wheels Black 5x7 thin elliptical liftarms 1x9 links Ball joint steering arms (6571) Rare tires (only came in 2 Technic sets) Lots of uncommon blue parts Blue pin long with stop bush DBG engine cylinders (unique to this set) DBG knob wheels DBG #2 axle connectors DBG 5x7 thin elliptical liftarms DBG pin connector perpendicular 2x2 bent (44809) LBG 1x2 gear rack (unique to this set) Tan axle and pin connector perpendicular split (unique to this set) Tan 1x3 cranks Trans red 7x3 bent liftarms White bushings White half bushings White pin connector perpendicular 2x2 bent (44809) White steering arms (unique to this set) White steering knuckes Yellow bushings Yellow pin connector perpendicular 2x2 bent (44809) Yellow pin long with stop bush As I said, this set has more rare parts than any other Technic set. This clearly identifies it as a 2004 set. What is really striking about it is that, as you build it, you see that almost none of those parts really needed to be those rare colors. They could have been common colors and the model would have looked nearly the same. I have parted out a few of these in the past because they can often be acquired for much less than the value of their parts. Also, if you happen to need some of the rare parts, they can be nearly impossible to buy individually on Bricklink.

This set is from 2004 when LEGO was going crazy with making in every part in every color they could think of. There are indeed a wide range of rare and unique part colors in this set. In fact, I think this set has more rare parts than any other set I own. Unless you own 5000 copies, it is not tons though. ;-)

That's odd. I have never had a problem using V1 receivers with servos. I have lots of models that use this configuration.

You need to make a supercar in a scale to fit your V-8 in it!

I remember trying to order pneumatic components from LEGO when 8110 came out and was told that they only sold the pneumatics as a pack. In other words, you had to order the bag which contained ALL the pneumatic components from 8110 and could not buy just actuators. Jim's review shows that all pneumatic parts come in a single bag again in 42043, so it would not surprise me if they are only available the same way.

That's certainly a complicated way to rotate a plate and, therefore, awesome! Thanks for sharing the thought process that went into the programming.

That's certainly a very unique idea. Well done!

You have run into the limitations of the PF system intentionally put there by LEGO. You are going to get both fast and heavy at the same time with Power Functions. The XL motors have the most torque, so if that's not enough for you then you'd probably prefer proper R/C. There is a current limit on both the battery box and the speed controller, and you'll hit them pretty fast with XL motors. The SBrick has much better current capacity than the PF receiver, so if you ditch that it will get even worse. If you do come up with a way to increase power, you'll start destroying LEGO axles.

I was going to ask for that part, but I felt guilty asking for something so rare. I'm glad it got done anyway! I'll make the updates to my file.

Merging with the global topic....

I was right. It was quite interesting. I've completed a draft version of PDF instructions. This is what I'll be using to build my copy. I can report back if I find any problems with them. I'm going to build it with a slightly different color scheme so we don't get them mixed up.

That's because Ttimman just goes and uses Sariel's work place while he is sleeping. It's kind of creepy.

I've built this model and can confirm that it is excellent.

The arm doesn't look exactly scale, but I actually like it because of that. The huge throw on all the dual linear actuators makes it look beefy. It is a common misconception that adding an actuator in parallel adds more power, but actually it doesn't make any difference if they are being driven by the same motor. You actually lose a little power because of the extra gearing. Adding an actuator only helps if you are slipping the clutch. On the other hand, doubling the number of pneumatic actuators in parallel actually does double the power.

I like it! A very unusual looking design. I also like the way you used a lot of perspective on your photos to make it look particularly huge.

Alexander has already done most of the work by creating and stepping the file. I'll probably add some LPub commands and export a version of instructions for my own use. If others and interested, and if Alexander is OK with it, I could post them. I don't plan to do any major reshuffling of the file so I can't promise they will be of my usual quality. I hadn't thought about the balance, but as long as there is sufficient drag in the idler axle, the mechanism would rotate even if unbalanced. Of course, any friction here is also drag that bogs down the motor and creates heat and wear. I was actually thinking about this as I drove home from work last night. While 1 revolution of a wheel sounds like a nice round, logical way to produce a 90 degree turn, there is nothing inherent in 1 revolution that makes this so. For example, a very small wheel would only rotate the vehicle a small amount in one revolution. A 90 degree turn has an arc length of (PI*W)/2 where W is the width of the model between the wheels. The circumference of a wheel is PI*D. For one revolution to equal 90 degrees, these terms have to be equal. This means the width between the wheels needs to be exaclty 2 diameters for this to work. Let's see if it is: In the file it is very close but not quite right. This is probably because the tires in the file are not actually the right tire and may be very slightly different diameter. So to use these knobby tires you might need to adjust the spacing slightly. Note therefore that there is no requirement that there be 1 revolution of a wheel per cycle. It could be anything, but the spacing of the wheels would have to be adjusted accordingly. I like the simplicity of 1 rev though. Note also that the drawing could technically be made much smaller by using smaller wheels and locating them nearer the center of the machine (easier said than done). This would also result in reduced stability. It all depends on what is meant by initial conditions. The BUILD is sensitive to initial conditions in that the relative position of the cams is important so that the machine is programmed correctly. However, once the machine is built starting a drawing is not sensitive to initial conditions. You can start anywhere in the curve. Your updated file hasn't been moderated yet so I can't see it, but I'll update my version of the file once I see what to do. For these particular animations, I just manually rotated everything in MLCAD, did screen shots from LDView, then put them together in GIMP. This is a laborious process because LDView recenters the model every time you reload, so the frames are not aligned. I needed to manually re-align them. The animations on my Technic Fundamentals page were rendered in POV-Ray and in those cases I programmed the equations of motion to get automated output of the frames. I could have done that for the Scotch yoke (simple rotation and a sine function for the translation), but the equations for the Geneva mechanism would take a lot more derivation, and the Tomy armatron mechanism involves step functions so didn't let itself to programming. In fact, I still wasn't completely sure how it worked until I finished creating the frames. Incidentally, deriving the equations of motion for the Ackerman steering mechanism was quite difficult!

Time to talk about the lower half of the model: the power and drive system. Although my initial focus was on the Geneva mechanisms on the top, now I think the bottom is even more interesting. The motor input is shown in green, the "switches" in dark tan, the "Tomy armatron mechanism" in red, the Scotch yokes in tan, the transmission in turquoise, and the output to the wheels in white. Let's start with the easy part, the input gearing. The central horizontal axle is the input from the Power Functions L motor. The bevel gears go up to the vertical axle and up to the brain. The additional 1.67 ratio here means that the total ratio between the motor and the Geneva mechanisms is 333:1. The lateral horizontal axle powers the "Tomy armatron mechanisms", my favorite part of the model. The 20 tooth double bevel gear is an idler and doesn't change the ratio. The drive axles are turning at all times when the machine power is turned on. The "Tomy armatron mechanism" converts commands from the brain into a fixed number of rotations of the output wheels and then stops. How does it do that? It's really hard to explain so I spent all day yesterday making some animations which make it much clearer. (The green axle and gears in the animation should really be moving, but that was too much work to do manually and wouldn't work at this frame rate anyway.) The red assembly serves as a clutch of sorts, engaging and disengaging itself from the downstream components. The green drive axle runs through the middle driving a 16 tooth spur gear. This in turn drives the two dark gray idler gears. When this mechanism is held in the starting position by the dark tan cam stop, the idler gears are not attached to anything and just spin. One of the two idler gears spins almost frictionlessly on an axle, but the second is mounted on a friction pin shown in yellow. This friction causes drag which tends to make the entire assembly want to rotate. When the dark tan stop is released by the brain, the red mechanism is free to rotate. It spins 1/4 turn and then stops against the tan slider. In this position, one of the 16 tooth idler gears is connected to the transmission and drives the wheels. In parallel, the tan slider is also powered and starts to translate. When the slider moves a certain amount, the red assembly is again free to rotate another 1/4 turn. It keeps driving as the second idler gear engages. When the tan slider oscillates back to its starting position, the red assembly is again released to rotate 1/2 turn back to its starting position to stop against the dark tan cam. I've given some thought as to why the yellow idler gear support is a 3L axle pin instead of a regular 3L pin. Axle pins are made of a softer plastic than regular pins, so my suspicion is that this was chosen to achieve a particular amount of drag. So what makes that tan slider oscillate? A Scotch Yoke! When the "Tomy armatron mechanism" is driven, it in turn drives the Scotch yoke. The Scotch yoke controls the motion of the "Tomy armatron mechanism", so the system forms a feebdack loop. The animation shows how a 1 revolution rotation of the red axle produces one oscillation of the tan slider and therefore one drive cycle of the "Tomy armatron mechanism". The whole point of all of this is to drive the wheels a particular amount, so let's look at how this attaches to the transmission: At start, the whole transmission is in neutral because nothing is connected to it. To be more precise, any rotation of the wheels is locked by the worm gears. The yellow gears are driven by the "Tomy armatron mechanism" when engaged. They drive the blue mechanisms through the worm gears which power the Scotch yokes. The orange axles power the right wheel drive system and the red axles the left. In both cases they drive the ring gear of a differential. Let's look at the left side. The red gears drive the ring gear of the tan differential. Since the orange gears are locked by the worm gear, the opposite white differential ring gear cannot rotate. The white and tan differential outputs are linked together. Since the white gears cannot rotate, one of the tan diff outputs (the white one) cannot rotate. This causes the output to be driven to the turquoise at 2x speed and then out to the left wheel. The right hand wheel also moves in the opposite direction, but instead of the ring gear being driven the tan spider gear is driven. This means the torque goes straight through to the purple output to the right wheel but at half the speed. The gear ratios are extremely important here not just for torque, but because the output must have a very precise number of rotations in order for the drawing to work. Let's trace the gears to a wheel and see how it comes out. The yellow gears could be any ratio that provides enough power from the motor. One "cycle" is defined by one brain command which results in one trip of the dark tan stop, one rotation of the "Tomy armatron mechanism", and one oscillation of the scotch yoke. Therefore we can use one rotation of the blue gear as the definition of a cycle. Blue-red stage = 3:1. Red gear to diff ring gear = 1:1. Diff ouput = 2:1. Turquoise 1st stage = 1:3. Turquoise second stage = 1:1. Final stage to wheel 36 tooth gear = 1:3. So total for the left hand side is 2:3. This means that the left hand wheel rotates 2/3 of a revolution for every cycle. The other wheel rotates half as much in the opposite direction. Voila, right turn! (The left hand side rotating results in a right hand turn). There are various sources of backlash or lost motion in the system that could result in the slight loss of accuracy. The gears themselves have some backlash. The worm gears can translate a small amount on their axles before being restrained. This results in a slight loss of wheel rotation. The "Tomy armatron mechanism" is briefly disengaed while rotating from the first idler gear to the second. This might result in missing a gear tooth or two on the output. However, even if this happens it would slow down the Scotch yoke which would cancel out the loss. Hooray for feedback! I've really got to get some parts and start building this thing ......

If it was just an empty box with longer pneumatics in it, you would still think it was the best of all time.