Hopey

It's the rear stabiliser. There's no mystery to it.

Don't forget to build the B-model. I found it rather impressive.

At £68.99, why bother. For another £11, you can but the whole set get a further 1000 or so other parts and a pretty box.

I meant an adapter for the end that plugs into the battery pack. It already fits into the wall socket

So, can I use a different charger? I've got one that's designed for charging 9.6V batteries, which I think has a 7.2V setting as well. If I can find an adapter plug, will that work?

Looks good, but the yellowed rims are a little distracting. Might I suggest this?

Wow. I did a bit of reading, thinking maybe I could look into doing this as a hobby project (I've got a little bit of a background in Chemistry), but got as far as the MSDS on chromic-sulfuric acid and I've decided to leave it to the professionals

I'm curious about this too. Can you use regular chrome spray paint? Is there anything you should do to prepare them, like sanding them gently or washing them with that "oxy-something" detergent that re-whitens yellowed white bits? How many coats? Do the bricklink shops that sell chromed parts just spray them, or do they use some special method? I doubt electroplating would work on plastic, but something similar to that.

I think you've overestimated me, cause I don't quite get how it works. The motor drives the knob wheel. This meshes with the blue axle pins pulling that along The two cheese slopes push on some cams The cams switch the gearboxes Is that about right?

I put 8 rechargeable AAAs in mine, to get 9.6V. I haven't done any empirical testing but it works pretty well for me. How would this compare in terms of capacity?

By default, it's geared quite low to increase its torque, making it more able to crawl over obstacles and up inclines. If you want it to go faster (at the cost of reducing torque), it may be worth playing with the gear ratios before you do any major redesigns.

Out of interest, what's the source of these? Is it: a) Simple reverse engineering; they've created their own moulds, either from actual lego parts, LDD models, etc? b) Actual Lego moulds, which were once legitimately used by TLG outsourcing production, and are now producing unathourised parts? c) Something I haven't thought of?

There's another 12t/20t combo that you can replace, just before the drive goes to the uni joints. The one with the uni joint attaches here: You can replace these with 16t/16t or even swap the order of them (I think), gearing it up quite significantly. The original configuration is 12:20 x 12:20 = 0.36:1 With those reversed and 16 tooth gears in the hub, it's 20:12 x 16:16 = 1.67:1 = 4.6 times as fast, with correspondingly reduced torque. Which is probably more than you need.

So how much weight can it support? How about you flip the whole thing over and make it an axle? A true "floating" suspension . Driving it would be interesting. A chain would be my first though, but that would pull it forwards. Maybe two chains? One in front pulling forwards, one behind pulling backwards? (with tensioner springs)

At the moment it is, but that might not last. There was a time when it was cheaper to buy second-hand CDs than to buy blank CDs onto which to burn copies...

It was on amazon.fr for €65 last week. I should have bought a few of them...

I'd guess because it'd get in the way of the tie rods. Edit: Whoops, didn't see it had already been answered (twice) cause it had rolled onto the second page.

Matt, we can't access your hard drive directly . Maybe you could upload the image to brickshelf, flickr, etc?

One would have to assume so; the box is the same size as 8110 and 8043 (and presumably 9398, although I haven't got one of those).

I may be completely out of my depth here, but I was under the impression that real helicopter blades (and aeroplane propellors) were thicker near the centre because the linear speed of the blade is lower near the centre, and a thicker aerofoil generates lift/thrust better at lower speeds.

I'd be concerned that the tail rotor isn't going to do it's job properly (anti-torque, to stop the body rotating the opposite direction to the rotor). Do you have any idea how much thrust the tail rotor will generate with the given gearing? Or how much is required? An alternative could be to have a second coaxial set of blades (or a counterweight) rotating in the opposite direction. This would of course increase the weight, but you'd not have the weight of the tail boom. This could be set underneath, which would be unstable but simpler, or actually coaxial on top, although the only way I can think of to do this would be to use a small turntable. And of course any added mechanism adds weight. Perhaps a simple proof-of-concept would be to forget about balancing and anti-torque, and simply tether it (with string or whatever) to demonstrate that you can generate enough thrust to lift the motor + batteries, then (assuming success) add weight until it doesn't to see how much you've got left over. Just a thought.

Right, but that's a technic set, which kind of misses the point. Most technic sets have a lot of technic parts :)

So a few weeks ago I picked up a 7707 "Striking Venom" second hand on ebay for £11 including postage as a present for my kids, even though I'd never heard of the set (or even the theme) before. As I was helpling them build it, I realised how many technic parts it contained, many of them I think could be quite useful for MOCs. Highlights include: x8,x8,x8,x6 (somehow I didn't have any of these) x16,x4 +x8,x4(!) , along with a bunch of connectors, axles, etc. I struck a deal with them that they could play with it for a couple of weeks, after which they could keep the robots and I would strip it down for the parts I wanted. I've been doing this tonight, which prompted me to wonder (and ask): What system sets (is this the right term for non-technic?) have you folks bought for the technic parts they contain?

Heh, sorry about that. Looking at the parts list confirms this; there's 4 of the light CV part and only 2 of the dark one, so this must be used to drive the rear wheels.

I think that you can fit the cv joint directly to the hub, the same way as is done in 8070, which (again like the 8070) puts the CV joint right in the centre of both axes. If so, it shows some rather forward thinking was involved when they were designing the portal axles for the Unimog a couple of years ago.