andythenorth

Oops, I forgot one important thing, with two motors per axle, the motors on left / right sides run in opposite directions. To solve this, connect all the motors on one side to a PF Switch, and reverse them. I've got a prototype build of an L axle, it's too wide, but eh, haven't seen a way make it narrower yet. Video https://www.flickr.c...in/photostream/ The trailer has 1.3kg of wooden blocks in. The truck is fast on level ground, but pretty gutless trying to get over any kind of bump. Tandem (4 motors) or tridem (6) would have a bit more pull. The axle is exactly one tyre width wider than the 8258 tow truck, but I think it can be slimmed down by at least 1 stud, losing some strength. Off-topic - the axle is exactly correct width for the 42009 B-model (container stacker). It has plenty of power to move the stacker, and looks like it would drop in without major surgery (the fake engine would no longer turn mind). Full RC container stacker anyone?

Thanks for that, very useful :) Out of interest, is there a constant supply on the 9v wire when connected to the PF receiver _output_ ? Thinking about powering lights from it...

I reckon, let them get on with shipping v1 (non beta) SBrick, they have £88k of kickstarter funds (plus whatever other investment), and (I assume) a growing salary bill to pay. v1 hardware won't be 100% reliable, products never are, so they'll end up re-engineering some things, and they also have to keep developing the software and working to build a community. So they have plenty to do eh? If they do anything that in any way infringes TLG stuff, they've got a legal problem, and (unlike fan-produced parts), they have what could be a valuable business which is worth TLG suing. OTOH it would be nice to think that TLG would see Vengit as a partner who has produced an interesting PF addon.

So flip 9v and 0v, leave C1 and C2 untouched? I can start chopping up wires to figure it out, just wondering if anyone has done it before...

My kids (3 & 5) wanted the 42009 container stacker built much more than the crane - based on the box pictures alone. I haven't built the A model, but the B model is great, really solid, and probably more fun to play with than the crane. The B model of 8049 is also great, better than the A model imo http://brickset.com/sets/8049-1/Tractor-with-Log-Loader The B model (crawler loader) of 8043 is outstanding and would have made a good A model. B model of 42008 (green truck) is appalling. The A model is poor too. Not because it's green, but because neither A nor B model seems cohesive, and neither of them is fun to play with (with apologies to the designer for harsh comments). http://brickset.com/sets/42008-1/Service-Truck

For both technic and trains, it sometimes would be handy to be able to reverse polarity in less space than the PF switch requires. I'm guessing that a third party wouldn't see a financial return on a specialist part for such a niche use. But eh, it's a thought. The part-modifying solution is to snip the wires and resolder. Anyone know which wires are +ve / -ve and which are control?

Yes

But hard to follow when you're not a native speaker of the language.

I made a couple of (really bad) videos to show the speed of another truck. This one has 3 XL motors, so it's not especially fast. All 8 wheels driven. It was only running on one battery box, the second set of batteries was flat. It goes a bit better on two. Hauling the 42009 crane B-model, and 1.3Kg of children's wooden blocks. It will pull a 20Kg child, but only on dead level ground. Videos are very low quality

BTW, if you want better performance from the train, and you're not afraid of hacking the lego parts a bit... ...get a knife or tiny flat screwdriver, and very carefully remove the o-rings (rubber traction tyres) from the 4 unpowered wheels on the engine. They're only needed for the powered wheels, and they cause the engine to slow down on curves. (Those unpowered wheels bind on curves because the outside wheel needs to go faster than the inside wheel on the curve, but they can't because they're on a single axle. Removing the traction tyres means the wheels can slip, which reduces the problem).

Ha ha ha ha. There'll be longer pneumatic cylinders from TLG before that happens.

I had a similar issue. Two cargo trains (two kids). One of them, the battery box won't power on. Fairly certain that the batteries aren't making contact, but all of mine are rechargeable, with thicker casings, so can't prove it. Christmas day tears avoided because we already have other battery boxes, which power on fine with the batteries I have. Also (off-topix) - I've seen this said on these forums before but not really experienced it - the clutch power of some parts is very poor in the sets my kids have this christmas, the 1x2 grille tiles particularly.

It's probably a City Police set, most likely a bank robbery (Metro Money Deposit Pursuit).

I dunno. I think that Power Functions is probably on the way out. My evidence for this is that within last few years, we have had two new motors (L, Servo), a new version of the IR receiver, and a recent change to the cable moulds. All points to TLG abandoning PF in my opinion. Oh wait, maybe it's just rumours starting out of absolutely nothing. Yes. That might be it.

Gearing: so you have a range of gears available. 3:1 is the 8 tooth gear with the 24 tooth gear. You can also use the 12 tooth with 20 tooth (1.667:1), or 16 tooth with 16 tooth (1:1). All of these fit the same stud spacing. The thin liftarms: if you look at my pictures, there is reduction with a black 12t gear and a tan 20t gear. These are trapped between two yellow triangle liftarms, which are 'think' or 'half-width'. You do need to trap the gears between two liftarms (or they'll slip), but you don't need to use 'thick' or 'full-width' liftarms. In this picture one of the two yellow triangle liftarms is removed so you can see the gears https://www.flickr.c...157649485436319 It would normally trap the gears, and be held in place by the red 2-long axles (which are poking out the back of the yellow liftarm that is left in place). EDIT I've ordered some L motors, because I might try and build a truck like this now you've got me thinking on it. Won't be until after christmas though.

I don't think you need the second reduction with your wheels. They're 62mm vs. 106mm on the wheels I'm using. Smaller wheels = lower rotational speed, higher rimpull torque, no need for the extra reduction. I didn't do any maths to check it mind. You can try 12:20, 8:24, or 16:16 gearing to get the best combination of speed and torque you want (it will always be a compromise between the two). I'd build a rough test rig when you get the motors and see what it pulls. Brickhaus's mockup is much simpler than mine, which is good. If you don't need suspension, then you don't need that kind of super-strong live axle. If you can use thin liftarms though either side of your gears, you'll save 2 studs width.

Picture quality is poor, but I disassembled the Rolligon a bit to show the structure: https://www.flickr.c...57649485436319/ - you don't need the portal hub with 8:24 gear - you do need the 12:20 gear in the triangle half-stud liftarms - the half-stud liftarms are the key to keeping it strong whilst keeping the gears meshed. - not visible in the photos are half-pins which attach the motor to the nearest triangle liftarm. http://www.bricklink...tem.asp?P=32002 - also not easily seen, but these parts are used to mount the motors http://www.bricklink...tem.asp?P=48989 You'd need to adapt my design a bit, but not a lot. You mount the wheel on the same axle as the 20t gear, with a liftarm (dunno which part) braced from the 3x5 L liftarms. Mine has two axles on parallel walking beam suspension, which gives it a high rough-terrain capability, but you don't need a lot of suspension for heavy haul (and it will tend to hop under load if it has too much suspension). EDIT, oops, you may find you don't have enough ground clearance with this design in combination with your wheels (wheels may not even touch ground) Probably solvable with more thought (move the motors to the bottom of the rectangular 5x7 frame, instead of the center?).

https://www.flickr.c...57624355112320/ Lit by bright white LEDs that cost maybe £0.30 each about 5 years ago. The power on the bulldozer is a LifeLites brick that is no longer available (they still make other products for lighting Lego - http://www.lifelites.com). You can power LEDs from Lego battery boxes. For that you'd need to split open the wires on a Lego cable (can use one of the extension cables, they're cheap). Unless the LEDs are rated for 9-12v, they'll need a resistor wired in series. I think there's some rule about whether the resistor has to be on +ve or -ve leg of the LED, can't remember. Soldering is best, but you can avoid it by using screw blocks if you have space. http://www.screwfix....ack-of-10/25545 You can also cover any bare metal with heatshrink tube, which you put over the wire, then heat with hot air. Looks neater. I forget the LED size, but I think it was 3mm. Sometimes these fit in a technic half-pin perfectly, other times they need the size reduced, which can be done with a file, turning them in a drill.

In the case of both wheels powered by one motor yes, a differential is needed. In the case where one motor is used per wheel, the differential is not needed. @aminnich, my truck has the L motors offset either side of the centre line of the axle. Mounting them to a 5x7 square frame results in a very strong assembly. I have two sets of reductions, and the portal hubs, for a total width of 19 studs between the wheels. You only need one reduction, and for the wheels you're using, you don't need such strong hubs. I think it can be done with 13 studs between the wheels. For comparison, the 8285 tow truck uses the same wheels you have, with 11 studs between the rear wheels (which are double-tyres). For a heavy haul truck, that would be ok. I think you could even fit in primitive suspension (oscillating axle or walking beams). I don't have a good picture, but you can just see the L motors on the front axle in this picture. Don't be misled by the huge tyres I'm using, they actually demand quite a narrow chassis, and the truck in the picture is not much wider than the 8285 truck. I'll try and post better pictures later.

What does it cost? About $10 or so? It's £8 sterling. Bargain. On the other hand, there will thousands of them on Bricklink for years. Lots out there. Probably not your biggest dilemma of 2014 either way.

And if it could cost less than the XL, and be 50% more efficient that would also be good. And if it came with a free unicorn

Have a look at this thread http://www.eurobrick...howtopic=103615 Not cheap though I think

Is it April 1st already?

Nah I've got nothing. I tried. I honestly did. I thought really hard. But I didn't come up with any other solution. Do you have suggestions?

If you actually feel that way, I can only think of one sensible solution, and that's to stop buying Lego, right now. All Lego. And campaign hard for others to do the same. If you feel exploited, but you collaborate with those who you think are exploiting you (without any coercion, and let's be clear, nothing forces you to buy any Lego, unless you actually have a genuine addiction that would be medically recognised, in which case, you have my full sympathy for an affliction you didn't ask for), then either the exploitation is not materially real and only exists in your mind due to an error of perception by you, or it's an exploitation that you are prepared to accept because, for example, you consider the trade-off to be worthwhile, or because you have a deep pyschological need to submit to external forces. AFOLs have been printing some really nice (original design) parts in 2014. People are reporting quality is not yet Lego standard; finish, colour ranges etc could be better, but from what I've seen & read, they do look pretty good, so yeah, probably matter of time.