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A simple explanation for why the design of the #8043 was probably approved up in the design department may be that the LAs that the designers use are prototypes LAs built with more strict manufacturing processes. Hence, when TLG checked, after the numerous complaints, they opened 50 boxes meant for distibution and built all of them, and almost all had the described problemed from the custosmers. According to my reasoning, I don't think it's the designer's fault; it's the LAs manufacturing process/quality/ultimate design specs. Nonetheless, I'm happy the LAs, it's a great addition to the lego parts lineup and kudos to LEgo that responded quickly to the uproar of us, the AFOL! It's just my opinion!

Why aren't you using chain links? I found this a couple months ago, but I can't remeber from where; I was really impressed and never got to build something similar

Amazerful!!! I've been trying to build one for a while, never got to finish or get satisfied with my results. with 2LegoOrNot2Lego's heavy loader a couple months ago via technicbricks and now han's WITH instructions, WOW, it's going to be a busy next couple of weeks (and a Bricklink expensive shopping spree!!) This MOC is well worth the front page!!!

Contacted TLC on august 25th and just got my service pack today by mail. Order was well packed. Package was shipped on September 27th (well what waswritten on the accompagning letter) All 4 LAs and small parts were included. Don;t know when i'll re-build my excavator to test it out...

Very nice and very cool! It's very well built and really captures the essence ofthe machine in Lego. I've actually never saw a specific excavator with extendable arm around here (Canada). But the spinning head ("boucharde" in french slang) we use relatively often as a 'quick attach' on large regular excavators, PC-400 or bigger, to 'scrape' and 'smooth' the surfaces of recently blasted surfaces. Now did anybody devised a quick attach system for lego excavators? I suspect the new MiniLAs will be perfectly suited for this.

My first real job was as a rock-blasting inspector for excavation. Explosives, seismographs and big toys. I'd give the "OK" when it was time to activate the explosives... Hence the name!

That's a nice idea to add a 'two block' sensor. Never thought of adding one on a lego crane. Might have to borrow your idea someday! I don't have a tough sensor brick, let me look into it and I'll come back.

Still not available in Canada, and the weird thing, there's not even a price shown... It's a very nice collection if parts, I'd buy a second set.

I haven't bought the 8053 but built it from spare pieces, both A and B model (the B model is nice) and I agree that maybe, MAYBE, the 8053 is a predecessor for a larger scale 4x4 fully RC all-terrain crane (picker) which is one of my wish-list sets that TLG will produce. I've built a picker as my first MOC one over a year ago and been hoping for one since then! http://mocpages.com/moc.php/155161 And one of the best I saw, Cheng Fei's: http://bricksmal.com/moc/cheng-fei%27s-rough-terrain-crane/msg2616/?topicseen#new

Very cool, in the youtube video, there's a mention of fan-made instructions for these 4x4. Where can you get those? The off-roaders look pretty rugged and efficient!

My nephew is still a bit young for technic, 3 years-old. Got him a classic all-steel, indestructable tonka dumper truck. He's a real demon.

Anybody got news for 1h2011 sets? Rumours or facts? I was checking out TBs archive and the first rumours concerning 1h2010; the set numbers and names came out August 15th 2009. Just wondering if anyone had news.

Hi all, with my brain overloading with work and my upcoming large project, I stopped by my local TRU to buy a gift for my nephew and saw the 8045 on ligquidation. So I've decided to pick one up and built the A-model right away. It looked very basic right from the start so I've modded it to look a little bit more functional. It's so satisfying to have a project done in 1 hour... Now back to the large puzzle!

Never had this piece, but it looks like there's some friction on the rotation; doesn't it defy the purpose of having a pendular suspension? Unless I misunderstood where you want to implement it.

Is that what you meant shimon? Because I like the compactness of it... Now on to Bricklink to get a handful of 32 long axles. -Nick

Thanks mahjqa, that's exactly the assembly that I was looking for. Actually i was playing with an old style differential and diffenrent gears last night, but the use of a changeover catch is genius. -Nick

Hi all, I have a problem that's been bugging me for at least a week now. I'm in the process of designing a 4 section boom powered by lego chains for a large-scale sky-trak (telehandler). Now I'm stuck on how to make a "sliding gear" on a axle a lot like how a worm gear "slides" freely and "grips" on the axle but with a 16t or 24t gear. By trying different combinations of odd pieces I found that a driving ring actually slides on axles joiners; but now how do i power this ring? Or is there another solution by using different pieces? Any advice is welcome -Nick

If I remember from one of the lab experiments from university, is that when a DC motor is under extreme conditions i.e. stalling, when the motor is barely turning under a lot of torque; that the amps going through the motor are very high and risk damaging the motor. If repeated enough, it could (and would) permenantly damage the coils inside and gradually diminish the efficiency. My advice, if your motor is stalling, stop, and figure out what's causing the strain. In the case of the 8043, multiple gears and various friction points could be the cause.

Good thinking; Put the total mass of the vehicule in the upper tray (m vehicule* sin theta) including the tires. By keeping the vehicule mass and size constant, we could get the "form factor" as a ratio of the mass pulled from the bottom tray at a certain speed and the kind of tyres used. Then repeat the experiment for different theta values and try to fit a curve trhough the points with a RK4 algorithm or similar. BLAAAAHHHH, feels like i'm still in university... -Nick

BTW mr rgbrown, i think we posted at the same time, I didn't even see your marvelous demonstration. With all these "serious" discussions, I think it's time to lighten up the mood with an old university joke. There's 3 students in a dormitory, an engineer, a physicist and a mathematician. In the middle of the night (let's assume there all sleeping...) there's a fire that breaks out. The engineer wakes up in a hurry, looks at the fire, rushes out to get the fire extinguisher and puts out the fire and goes back to sleep. The physicist wakes up, calmly looks at the fire, sees the fire extinguisher calculates the optimum angle to put out the fire, gets up and put it out with minimal usage of the extinguisher and goes back to sleep. The mathematician wakes up, sees the fire, looks at the fire extinguisher, looks back at the fire and the extinguisher. Whilst still in his bed, thinks about it, says to himself: "there's a solution" and goes back to sleep. Anyway, there's way too much variables to consider to effectively calculate the tracction of the lego tyres. In my opinion if we could just get the "form factor" of each different tyres (radius, width, tread form, dynamic response) we could really simplify this problem. BTW: there's 3 kinds of engineers: those who can count and those who can't. -Nick

Climbing up an incline mostly depends on the friction coefficient, angle of the plane, and location of the centre of gravity and mass of the vehicule. There's static friction which is higher than dynamic friction. The relation between friction of the tires and the surface at any given speed is not linear (meaning that the faster the wheels turn, the less friction you have, the less force is transmitted to the plane). But like ultimario said, it's a science of its own. Very nice demonstration nonetheless!

Mine reacts the same way as Jonas83 on the arm functions but the bucket movement is fine. But my transmission switching mechanism and my carriage functions work flawlessly (tracks and slewing). I did a little bit investagating on my model and found that if I hold the excavator by the boom (even when it's barely touching the ground) the main boom and dipper functions work perfectly. Even to the point it can raise itself without any trouble. I'm convinced that there's too much load on the lower bearing axle where the idler gears connects to the LAs. The flexing of this axle could create a lot of friction due to the bending. I might try to dissassemble it over the week-end to check it out. Also that kind of reaction from the M-Motors means that it's close to the stalling point, and it's not very good for the life expectancy of the motor and sucks way more current from the batteries. -Nick

I think so, but with some tweeking and LOTS of stability calculations, espsecially lateral stabilility. I'd suggest that the first boom section be either completly deployed (from 90deg to 135deg, 0deg being the closed position) and moved to the center of the carrier structure (for better weight distribution) with cables/winch attached to the back of the carrier. Crane design is really complicated and i'm just a construction civil eng; not a mechanical design engineer. -Nick

Very nice! For sure, very unique design; it really stands out of the traditionnal crane types. I sure would have appreciate to have a real one similar to this on my site a couple years ago... We were building high voltage lines in remote areas in northern Quebec. We had tradionnal crawler cranes (i.e. Link-Belt LS-78a) and the weight distribution and center of gravity of the machine made it very difficult to go over difficult terrain. Now, just suggest this to one of the crane manufacturers and you'll be rich!!! -Nick

Just a note for Fyredog; If I remember correctly from my school days the 9V battery has a very low internal resistance therefore dishing more current than 6 x 1.5volts AA. I don't know what is the ratings of the M or XL motors or if it could damage it... But for sure the 9V is not meant for "current draining" motors. Speaking of which, I have an old 9.6V deWalt battery at almost 1.2Ah ... there might be some testing ahead... -Nick