hoeij

A few weeks ago I bought two 7740 sets to make 1 nice long train. And yes, I do have the feeling I paid too much...

That makes no sense. It's much better to use one battery box. Use AAA rechargeable batteries. They have lower nominal voltage, but can deliver more current than alkaline batteries. That translates into: a lower top speed, but higher pulling power (both of which are good for cargo trains).

Before they re-release this, they should first fix the design flaw. I think the best thing lego offers are the 3-in-1 sets, especially when the 3 models differ significantly from each other. That's what I hope to see in the train theme too. The most interesting train set so far has been the 10183, that, with 30 different models, offered a great way to learn new building techniques (this set went on sale for $50, great for us, not so great for the company). Something like this set, with new models and a new color scheme, that would be the ideal train set.

For those who have 8110 as well as the 8868 Air Claw Rig, how do they compare in terms of play value? I have an 8868 (love it) which has similar functionality (minus the suspension and the winch), and I haven't yet decided if I should get this one too.

It does not matter too much how many volts the battery pack produces, as long as it can produce enough amps. The 8878 does produce enough amps; it works well.

The battery box only has a connection for all 6 batteries tied in series. My battery charger, on the other hand, has a spot for each AAA battery separately. Of course, it is possible to run a current through the 6 batteries in series, charging all 6 at the same time, but then you wouldn't know if some batteries are already fully charged while some others are only half-charged. What would happen if you overcharge some of the batteries?

Recent years have seen large price increases, in particular Cafe Corner and Market St. I think the rise in those prices is partially due to the overal rise in lego sales. Lego has seen increases in sales in the last couple of years, so that means that there are now more lego buyers then there were a few years ago. That in turn means: more people interested in buying the sets from a few years ago. As long as the total number of lego buyers is steadily growing, you are likely to make a profit if you buy lego flagship sets. If the lego costumer base stops growing, then it's not so clear if prices will still go up enough to make it worthwhile. Coming back to Cafe Corner: the newer modular end up increasing the price of Cafe Corner because the modular houses are so nice that when people buy them, they get a taste for more. On the other hand, when the new passenger train came out, it caused the previous one (7897) to go down in price. Somehow, you have to know to hold on to Cafe Corner until the price became insanely high, while 7897 should have been sold as soon as you get a good profit. Trends usually do not stop very quickly, but also don't last forever. In the last couple of years, buying lego flagships would have been profitable, so it seems likely that this will still be true right now. I don't think this will always be the case though, if lego overall sales starts to flatten out, then demand for the sold-out sets will reduce as well.

Can rechargeable batteries be safely charged while sitting in the AAA battery box?

Prices can go up but they can also go down. The safest bet is if you buy a set that (a) you're willing to sell if the price goes up, and (b) you'd be happy to keep for yourself if the price doesn't go up. The train 7897 went way up in price after it sold out (for a while, lego wasn't selling any train sets). But its price has come down since then (probably because there is a great selection of new trains out there right now). So to make good money on that one, you'd have had to sell it say half a year after selling out. Some other sets, like Cafe Corner, have been increasing in price for a much longer time, so to make the best money on that one, you should not have sold it after half a year. So, how long you have to hold on to a set is not always the same. Still, if you buy them low enough (say at buy one, get one 50% off, at TRU) it seems like a pretty safe bet that you'd make money, provided that you buy top-end set, the best ones out there (like the modular houses). For lego trains, the top-end sets are clearly the Emerald Night and the Maersk. If you buy some to sell at a profit, you probably do not want to keep them for a very long time (say 10+ years) because you have to factor in the cost of storage, and there are many wonderful old sets that are quite cheap (e.g. even a legendary set like 8868 air claw still sells often for less than $100 on eBay).

I would use one 7.4 V LiPo pack. Light-weight and lots of amps, more than enough to power 20 lego motors. In the experimental phase, I would not use an 11V pack because if a motor stalls (which can of course happen during experiments) then 11V will burn out the motor much faster than 7.4V (note: 7.4V is also enough to kill a motor if you stall it long enough, but I think some of the lego motors have thermal protection built in (to double-check, google: lego 9V motors compared)). You can use more than the stated voltage limit provided that you don't let the motor produce too much torque (which translates into: too many amps).

Still, on the sides of the train, you have some nice details in the middle of the train, but then in the back there is suddenly a square sticker of a different color. As for the pieces, the hobby train set 10183 probably has all the pieces that you want (the best thing about 10183 is the instructions for 30 models, written by AFOL's, that contain lots of good ideas).

I have spare 12V wheels in case you need some. Then again, maybe you want to keep the red pins, makes your train quite unique!

The most likely reason that the slow ones are slow is that all their lubrication has disappeared, and so they now have a lot of friction. To overcome all that friction, these slow motors will need to draw more amps than the fast motors. So the slow motors will run warmer (and hence, wear out more quickly) than the fast motors. If your slowest motor is much slower than the fastest motor, I would recommend that you lubricate it (open it up) before you put a lot of miles on it.

Great review. I don't plan to buy this set because I already have too many red trains (mostly from the hobby train set). But after reading this review I'm starting to see that this is indeed a nice set that will surely do very well.

As a kid, I've used the blue 12V transformer for every electrical experiment I could think of (at one time I used diodes from an old TV to make a rectifier, turning the AC outlet of the transformer into DC, then added to that (in series) the DC outlet to crank up the voltage even more, and then used that to power a lego vehicle with a motor from an old tape recorder). My transformer also has seen lots of short cuts (as a kid I liked the sparks). I have come to believe that this thing is indestructible; if it were destructable, it would have been destructed. I've also noticed that when you short the AC outlet on the blue transformer for too long, then it shuts itself off for a little while, and after that, it works again. So there appears to be protection built in. So I think that no matter how much load you put on your transformer, it's not going to break. The voltage output does decrease with additional load. With 4-5 motors, the DC output may drop to about 6 volts so the top speed is not going to be as high. By the way, your motors, if you run them with no load (no train, just the motor) on the track, do they run at roughly the same speed? (this is a way of checking if they're good. If all the motors are in excellent condition, then their speeds will be fairly close to each other).

The transformer can deliver about 1 amp, and a 12V motor uses about 0.25 amp. So two motors on one transformer is OK. Most of my trains are 5 feet long and have one motor, one of them is 12 feet long and has two motors. I can run a 5-feet and this 12-feet train together on one transformer, so that's 3 motors on 1 transformer (I'm using a blue transformer, but I'm sure the grey one can do it too). Note though that if I start up the second train, the first one that was already running slows down significantly (in other words: the voltage on the track decreases). Conversely, if I stop one of the trains in a siding, then the other one speeds up quite a bit. I have also tried 4 motors on 1 transformer. That works too (with an additional slowdown) but since that is running at the limit (1 amp) written on the transformer, I don't do that for a long period of time. The blue transformer behaves sort of like it has an internal resistance of 10 Ohm, meaning that for every additional 0.25 amp that the trains draw, the voltage drops by about 2.5 volt. Also note that these things "12V" "13V" are just estimates. With no trains on the track, the blue transformer produces about 16V at the top speed setting. Each additional motor lowers that by about 2.5 volts. So with 1 motor, you get at most 13.5 V on the track, and with two motors, the max is 11V (which is still more than plenty, I basically never run my trains that fast because that long 12 feet train is a cargo train that is supposed to go slow). I haven't measured the grey transformer, but since it is not a regulated transformer, I guess that it'll behave the same.

The more torque the motor has to produce, the warmer it gets. If you feel the motor to check the temperature, you'll find that after running it for a while, the temperature is mostly related to the weight of the train, the type of wheels you use, and the number of curves vs. the number of straights in the track. The voltage on the track has only a very small impact on how warm the motor ends up getting (except of course if the voltage is 0). For a 3-car train, all of this won't matter much, but most of my trains are 5 feet long, with 1 motor in it. With 9V wheels, the motor gets noticeable less warm than it does with 12V wheels (that's true at any voltage). Having the motor get less warm, to me that's a sign that it'll last longer. It's true of course that the motor can pull more (much more) when you increase the current. That 1 motor can pull a 10-feet long train, and probably even more, but then it'll warm up more quickly so I don't do that anymore. I think though that 12V motors are pretty sturdy and can last a long time (I do not know how long). Even so, with trains of 5 feet or more, I think it's prudent to lessen the load on them.

I wouldn't buy more of them. In a 20-meter loop, I apply power to 2 places on the track. That's enough so that there are no noticeable voltage drops anywhere. Even if I put the train at a very low speed, I still do not see slow-downs anywhere on the track. So one connection per 10 meter is definitely enough. Make sure that if you connect two middle rails, then there is at least some friction to slide one into the next one. That way you know that you have a good electrical connection (if you don't have a good connection, take that middle rail out, and use a tool to give a slight squeeze to the female part of the connector, and then put it back together again). If the track is already made, if there is a bad connection somewhere, you can quickly find it with a multimeter. Once found, a bad connection is easy to fix, and when fixed, the electrical resistance of your 12V track is lower than that of 9V track (in other words, you need to supply power to fewer places on 12V track than you would need for 9V track). One more piece of advice: I replaced all my 12V wheels by 9V wheels. This reduces friction almost in half. This way you can pull a much longer train, without increasing the burden on the motor. If I were using 12V wheels, then my 6-car 7745 (12-track length long) would be too much of a burden for one 12V motor.

I bought mine for $80 Buy-it-now on eBay. With auctions, I've seen some go for $100 or even less. I definitely think it's worth it.

I think that there is a capacitor in there. They are intented to be used in a large track, to remove high-frequency fluctuations in the voltage. Most DC motors come with a small capacitor attached to them (to remove the voltage-fluctuations produced by the DC motor). Older motors often do not (e.g. the old 4.5V technic motor has no capacitor). The 12V train motor does not contain a capacitor, that's perhaps the reason that lego made a track piece that has a capacitor. If you don't have these pieces, I would see no reason to buy them because I haven't noticed any difference, with our without a capacitor. But whether it makes any difference or not, you might as well use them since you have them anyway.

I added two more cars to another 12V train, the 7745. I don't remember the cost, but I do remember that it was quite cheap (the 7740 on the other hand...).

You should have bid on it. Half a year ago this would have been worth $800.

Yesterday, two lots of 20 9V straight track were sold for $63 and $64.55 and one lot of 40 9V track sold for $118.50 making the average selling price per 9V track piece just above $3.00 (the last time 9V track sold for $3.00 per straight track was several years ago). Perhaps a sign that prices for 9V straight track are past their peak and are slowly starting to come down or stabilize?

Not long ago, 9V track was selling at more than $5 per straight track (both on eBay and on bricklink). So $3 per track, although still expensive, is a lot cheaper than the prices in the last couple of years. 12V blue was older and cheaper than 12V gray track, which in turn was older and cheaper than 9V track.

By the way, a 7740 engine sold yesterday on eBay for 76 Euro's. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=180696014931&ssPageName=STRK:MEWAX:IT That would have been a good buy because for that money, you would have had a motor, lights, and your 3-car 7740 would have turned into a 4-car 7740 train. But as I mentioned, to get a good deal takes quite a lot of patience.