Bzroom

Attach a linear actuator to the motor. This will give you incremental control of the linear actuator position. You could use the linear actuator to drive a switch, a speed controller, or the gripper itself. I made a linear servo the other day. I just haven't had to time to take any video or pictures. You would still need a speed controller to control it though, just like the LEGO servo. Edit: You could also use a ratchet mechanism from one of the sequential transmissions to let you 'bump' between states.

A worm gear should give you a smooth and secure change over. The sliding nature, and open ends of the worm gear also lends itself to applications that have a limited motion, like throwing a switch. Since the worm gear has such a massive reduction and back-drive friction coefficient, you can gear up the input so that it makes the switch very quickly. You could connect the gear change switch to a small gear driven by the worm gear, or you might research solutions to actuating a pneumatic switch, often referred to as an auto-switch, for ideas on how to toggle your gear switch.

For parts, it was on sale, and just to have it/them all. I specifically wanted the blades incase I make a chopper moc.

As I see it, the advantage of the modular system would be to replace the modules. For example, switching out the solid rear axle to be a steered independent one, to give your model 4 wheel steering. To only use these components as a starting point for a model seems to have limited use. In other words, if you only build one pair of axles and one frame, then there's not much point in it being modular. The front and rear mounting sizes being different seems to prevent a lot of combinations. You should be able to put the same axles on the front or the back. The variety of the axles is subtle too. It would be cool if there were wide axles, lifted axles, dropped axles. Maybe you want to make a super car one day, and the next day you want to lift it like the Boss. The next day you want it to have tank treads. This would be a large advantage of the modular system.

Was it that gal who said "farming is free, you just put the seeds in the ground and food comes out, it's not rocket surgery?"

I bought this set but never built it. I was thinking about it after I saw this topic and decided to skim through the institutions. I always assumed the small turntable was a little swash plate. I had a technic helicopter a while back with a swash plate, why wouldn't this one come with one? Total let down when I realized it only had collective pitch and not cyclic. And the way its actuated, seems like under a small load the axles could just pull apart. Very disappointing. I'm glad I didn't build this model. :l of course I'm glad to own it though. :)

I would use what seems to be referred to as a Pendular Axle. You would basically create solid axles all the way across. Make this substructure as rigid as possible, and then fix it to the chassis with turn tables on either end to allow to tilt side to side. Attach your springs and steering would be contained within the axle substructure. Alternatively, if you want independent suspension, i would try to make the trailing arms connect to the axle at the widest point, and taper inwards towards the chassis. This way forces on the wheel will be directly in line with the tie rod, and the tie rods will practically from a triangle which will not skew. For steering, if you use two linear actuators they will get out of sync. I would try to come up with a very solid tie rod between the two sides, and put the linear actuators between the tie rod and the axle. Then you could use two or more LA's at that one interface, to make the steering stronger. If their clutch is overcome, it will probably happen at the same time and they will not be much out of sync. The clutches would allow them to become aligned again automatically i'd think. Also, it does look like you have some triangulation, but you'll need it in the right places. The best example i've seen is if you take a shoe box, and grab both ends of it, and try to twist it, you will see the box is completely rigid against all forces and torques, when applies through the edges. Now, take the lid off the box and try to twist it again. It will bend to shreads very easily. This is because the space frame is no longer fully triangulated. The lid face is now allowed to skew, and triangles resist skewing. You'll want a fully enclosed triangulated frame. You can either use a triangulated, box, or a tetrahedron or really any number of faces so long as every face is fully triangulated, and connected to other fully triangulated faces.

Red $ 1.25 Black $ 0.85 :/ but i want them to pop! Thanks Paul, i'll give them a shot. Good find. I must not know how to search correctly. When i found the item on bricklink, and then instructed it to sort by NEW, there was only one result, and it was the expensive one.

12m from LEGO customer service. On brick link, for "new" they seem to be about the same price. Of course i could roll the dice on used ones. I probably will. But I want some fresh ones for the photos. 4501304 new from LEGO actually cost $1.25

They're actually $1.00 for new red ones. Not very cheap. It's the most questionable part of making my moc plans available.

I'm using Hose Soft Axle for my leaf springs. Why? because they look good, work well, and are to scale. The suspension on the moc is pretty much useless at that scale, but it looks good.

They indeed will be a sight. Keep us updated. You should build a LEGO camera rig that allows you to take pictures of your progress very easily. And then a script that uploads them straight to EuroBricks.

As long as the air tank is pressurized and of suitable size the air tank will highly benefit. If after a few seconds the cylinders have depleted the air pressure in the tank, then the tank will have no benefit and the pump will have to charge both the tank and the cylinders at the same time, making response slower. But, if your air requirements allow the pump to sustain the air pressure in the tank, then there is a higher volume of air available at the expected pressure, which should allow the cylinders to be filled very quickly, until that pressure has depleted. IMO, if the air tank was not giving you benefits, you probably needed more air tanks, they will need to be pressurized, and the pump will still need to sustain your actual air loss rate. The tank acts sort of like a capacitor, a buffer of energy, when that buffer is depleted, you're solely relying on the pump or battery again, but with an extra load of recharging the buffer. :( After all that is said, too much pressure may make the model respond too quickly and inaccurately. Also, a very small pneumatic system, with one valve and one small actuator, surely could work with just a pump for maximum efficiency. No sense in charging a huge air tank just to move one small cylinder. But if you did have the time to wait for it to charge, that cylinder would respond VERY quickly. Ramblings complete.

Congratulations everybody. I can't wait to get my hands on one of these too. I'll probably build it without the internals and leave it on the shelf because it's so beautiful. I'll bang up my mocs and leave this one pretty.

Wow that's fast. I have two L's driving my new rig, it's fast but not nearly that fast.

My only critique is that the taper of the air ducts looks too simple, forced, single rate. and the front wing looks a bit too wide. Other than that it looks cool. Is it RC? That's obviously the next step. I appreciate what the 42000 did with so few parts

Best tool with the worst (least) documentation. Is therr a thread that compiles all these FAQ?

I've been trying to build my own custom tie rods for a couple days now. those parts would be awesome. Relying on a custom axle is kind of a drag though. I'd rather they be used with a beam instead.

You did an awesome job! Way beyond my expectations.

so close!

Please, can you refer to some examples of the difference here?

What I've learned about power functions motors: use as few gears as possible with the motors as directly connected to the wheels as possible. In other words, use a motor who's power is appropriate for where you connect it. It's not a good idea to connect two xl motors behind a complicated gear box. Xl motors could connect directly to the wheels. If you need that much power to turn your gear reduction, you've done something wrong. If you're going to gear down, you should use smaller/faster motors so they can provide the necessary speed, and won't over power your gears. So a rule of thumb, XL on the wheels, or an L under the hood. This applies to gearing up also, because its really still about torque.

I was just thinking about this when I was riding my motorcycle today. I'm glad I'm not the only one who doesn't find the fully sealed, pile-o-bricks method appealing. I'm not saying which construction method is more difficult. The fully sealed one probably is the most difficult. But its too much mass, parts, strength. It seems wasteful. If it causes technical issues then there seems to be no benefit for it. That being said, LEGO mocing is about using the right piece in the right situation to sell the model. If this is tons of beams stacked to make a wall, then that is a completely appropriate building technique.

I agree, this denotion has confused me. I'm looking forward to more explanation. I always assumed that syncronized, in LEGO gear boxes without real syncro clutches, referred to the direction of flow of power. If it were syncronized, as you said, the gear engagement would be seamless. To me a LEGO syncronized transmission is one that is configured to have the clutch gears spinning at the proper speed for selection of that gear. In most cases I don't see how that's possible and I eagerly await a post from Sariel who used the term frequently in his book.

Wow that looks extremely sturdy.