DeBriquesEtDeBlocs

I was wondering, why did Lego suddenly create a linear actuator when it has always been possible to make your own with existing parts ?

Ok, so after having browsed through most sets realesed since 2000, I picked up the one I liked the most fro those with ≈+800 parts, then checked their parts, prices, price per total parts and compared them. (I decided that below 45€ for 1000 parts was a good deal) Here's what I bought : 4404 Land Busters 25€ Germany shipping : 9€ (The seller rebuilt this set with the parts "he could find", I was pretty angry but got a refund.) 4896 Roaring Roadster 39€ (This one is really nice, huge, I noticed it is almost scalled for a Technic fig.) 4993 Cool Convertible 39€ (Not bad but it really sucks when there is no steering ! Also true for 4404 and 4955.) 4955 Big Rig 27€ (I wonder why this one is so small, is it not to concurrence another set ?) Free shipping (I did not plan on buying 4955 and 4993 but they were cheap and shipped for free) 7709-1: Sentai Fortress 30.75€ 7706-1: Mobile Defense Tank 12.75€ 8106-1: Aero Booster 9€ France Shipping 10.50€ (I bought exo forces instead of bionicles, they look equivalently cool and have no "useless parts". They contain lots of hinges. Great price but seller was incompetent, I'm trying to get the few missing parts.) 8289 Fire Truck 36.47€ UK shipping ≈18.50€ (As this one was relativly cheap I bought it only to get to now the new Technic building method and get the parts.) 7784 The Batmobile Ultimate Collectors' Edition - UCS 40€ France shipping 8.60€ (A huge model, lots of parts, bargain price !) 7317 Aero Tube Hangar 12.22€ 7310 Mono Jet Cruiser 1.18€ 7311 Red Planet Cruiser 1.34€ 7312 T3-Trike 1.34 UK shipping14.66€ (I didn't plan on buying the 3 little ones but they were auctionned by the same person) 7692 MX-71 Recon Dropship 31.28€ UK shipping : 11.86€ (The seller made a mistake and I thought I was buying 7644, I got a partial refund) 8275 Motorized Bulldozer 119.90€ (new) Free shipping (4 motors and 2 IR receivers, that's why I bought it) TOTAL 499.35€ (during the same period I received 463€ of extra money so it's almost like I got all this for free !) I thought about buying 10174: Imperial AT-ST or 10186-1: General Grievous (the only cheap Star Wars sets) and either 8458 Silver Champion or 8461 Williams F1 Team Racer (these are too rare and too expensive) but instead I'm going to just buy the ≈300 parts I don't have.

I can't see a custom u-joint in this maze of beams, only the standard lego part.

Do you have pictures ?

Hello, I plan to build a car that would weight about 1Kg. I want the rear wheels to be motorized (likely with an XL motor that I'm going to order) and have shock absorbers. I wish there was a real soft axle hose with crosses at the tips but it seems the only solution is to use universal joints and I'm afraid that they quickly break. Any feedback on this ?

I got some fiber optics from exo forces sets, the cable is much more flexible than I thought and that's a good new. However the beam is very concentrated, what part could I use to spread it again ? (It's for a car headlight.)

There is the micro motor 2986, is it compatible with PF ?

I got the prices from bricklink.com

Linear actuators seems to have replaced the pneumatic system in 2007 when the Power Functions appeared. I have never tried one or the other (I'm in the process of getting new sets) but I can already see several advantages for the actuators. Lets compare the cost of both : 48mm pneumatic cylinder $7 Pneumatic Pump $3 Pneumatic Switch $4.5 Pneumatic T Piece $0.30 195L pneumatic hose $20 (why is this so expensive ??) TOTAL $34.80 Linear actuator $12 Power Functions Battery Box $6.5 Power Functions M-Motor $14 Polarity Switch $10.5 TOTAL $43 The actuator system is more expensive (even though its polarity switch is not required). But, the other pneumatic parts can only be used for pneumatics, while the other actuator parts (the PF) can be used for anything ! This I think is the main advantage. The second advantage is that since it's electric, it can be automated and remote controlled. With the pneumatic system you have to press the pump and turn the switches. The third advantage I see is the precision and stability, that's why it's used in robotics. Pneumatics (at least in real machines) make the whole assembly shake when they stop or start their movement. Finally, there is the speed and the strength. Did anyone make comparative tests ?

I posted in Technic, Mindstorms & Model Team

waaaa that's exactly what I needed ! thx a lot dude

There's a 2mm difference in depth, does it look ok (if you have tried) ? Ok for the depth, but what diameter are we talking about ? The 44771 tyre and the 44772 wheel have the same diameter (68.8) so maybe it is the outer diameter for the wheel and the inner diameter for the tyre (so that it fits). But then the x1825 tyre has a diameter of 81.6 which can only be the outer diameter but now that's another measurement system, or I don't know. Actually this tyre has an R while the other tyre and the wheel have a ZR, what does it mean ? EDIT: It seems that the peeron information is wrong, bricklink says that the wheel is 56x34mm, now it makes sense.

By the way, what do the digits corespond to exactly ? For example for the Nitro Muscle it's written : Tyre 68.8 x 36 ZR, Tyre 81.6 x 36 R and Wheel 68.8 x 36 ZR

That's what I would call very small. I need a wheel of about 40mm in diameter (actually I don't know yet the scale of MOC). It seems fastidious to go through all the wheels and then check all sets - so I prefer to ask those who already know.

Hello, I'm looking for a medium, medium-large wheel (