Duplo Trains discussion

[zg0]

That is really crazy... If the child lets the locomotive runs under a piece of furniture, it will empty its batteries and damage its tyres before the parent can come to retrieve it. Stupid.

it still stop after 2 minutes, so not a big problem. afaik there are many "lift detector" malfunctions then train stops immediately after start, so lego decided remove it.

I noticed that too, and I agree that the new ones are more difficult. The hitch top has been widened to prevent slipping the hook over the top. They are stronger, so they resist better to kids who use force instead of brains. Unfortunately there are more and more of those :-(

sometimes a little force needed then you have a big train with about 10 wagons and 1st wagon must be with new hook.

Cute. However, you can buy a 90º crossover of the black, old style rails on the web, and it fits well, though the running surfaces are slightly lower down.

yes, I know. this was more "proof of concept" than really needed item.

Ah, well... Why not? It is a push train, not meant to go on rails.

if you don't have rails — yes. but if you have — child put train on rails immediately after box unpacking.

From separate bricks of the Duplo from 1982 of my daughter and the Duplo of 2013 of my granddaughter, we can build this "train" easily. It's not forbidden. In fact it will even run over Duplo rails too, though it will not go over switches.

1. yes. points, crossovers and possible — bridge are problem for car bases.

2. there are many push-train sets with train bases, last one — [6144]. so I don't see any reason to use car base in push train set except price of course.

3. btw there is another un-understandable story for me with push-trains. all push-train in last ~10 years have originally reversed bases — movable hook is at backside. this is not a big problem for sets with train bases, you can put base in correct orientation and everything works, but for [10558] this trick doesn't work. but old sets like [2452] have correct direction.

For example, there are at least three different scales for human figures in the normal Lego alone. Fortunately there is only one scale for Duplo.

yes, duplo has only one scale for humans. but there are at least three types with minor differences:

1. before 2004 year released ones.

2. after 2004 year type 1. possible produced in hungary.

3. after 2004 year type 2. possible produced in china.

old ones looks like don't have serious bugs. new womens have a big hairs, so they can't look forward in all duplo cars. also type 2 humans better fits into animals or old style motorcycle passenger place.

[StephanSz]

It's so cool to see a post on duplo trains :) I'm a big fan, as well as my son and daughters. I tested the curved track issues right away, but my track (all bought in the last 2 years) doesn't have these issues! 2 curved tracks fit nicely next to eachother on a plate. I can make a full circle fixed on plates without stress. 4 straight are just as long as 4 curved. In other words, all the issues stated on http://www.cailliau.org/ do not exist with my track. Now that's really interesting don't you think?

[Rick]

I tested the curved track issues right away, but my track (all bought in the last 2 years) doesn't have these issues! 2 curved tracks fit nicely next to eachother on a plate. I can make a full circle fixed on plates without stress. 4 straight are just as long as 4 curved. In other words, all the issues stated on http://www.cailliau.org/ do not exist with my track. Now that's really interesting don't you think?

There seem to be two types of curved track. The old grey track looks similar to the "wide" version, so I guess that's the older one.

The wide type is in the bottom left of this picture. As you can see, when fixed, two slim tracks fit nicely next to each other, but a wide piece of track also fits next to a slim version of the track, whereas two wide tracks don't fit next to each other (not pictured).

Also, although it's not very clear in this picture, two slim versions of the track seem to add up exactly to two lengths of straight track, ...

whereas it's quite clear from this picture that two wide versions are longer than two straight tracks.

[Robert Cailliau]

I went out, spent 25.60 CHF on 10506 and can confirm that StephanSz and Rick are indeed right!

Thus I have updated

http://www.cailliau.org/Alphabetical/L/Lego/Duplo/Train/Rails/Dimensions/

and will add to that page even more.

A few more things here:

1. set 10506 contains a railroad crossing, but with only one barrier!

2. I had noticed that the switches, which are a "meld" of two curved rails, were slightly different. In fact they match perfectly with the type-3 curved rails.

My hunch is this, but please note it is only a conjecture: the mold maker goofed up the curved rail molds but not the other ones. How, I have no idea. The mistake was only discovered late, possibly when thousands of curved rails had been produced and shipped. Since only people like us (Adam, you started it all ) on this forum would worry about such small issues, no corrective action was taken until the molds were worn out. But only someone inside Lego could tell us what really happened.

One thing is certain though: the mistake was not through an accidental small scale factor, because then the sleepers would not fit any plates.

[Hey Joe]

You're probably correct Robert. It explains the big price jump that zephyr1934 noticed; they were dumping the botched track.

Joe

[Robert Cailliau]

You're probably correct Robert. It explains the big price jump that zephyr1934 noticed; they were dumping the botched track.

Joe

Possible indeed. Given that there are two switches, 5 straight, 8 curved, one road crossing and a few bricks in the set 10506, I found 25CHF not expensive however. It looked to me rather like a very good price, compared to that of a pair of switches alone. But I agree, I do not understand the pricing nor the evolution of sets. And one always ends up having too few straight tracks. It's a good thing there is the BrickLink, so I can buy (ordinary) parts in the quantities I need. The sets in the shops are often frustrating.

I wonder if there is a site (other than the BrickLink) that combines all the information known about Lego parts. The BrickLink has the part numbers and colours as well as some info on whether it is an "old" part or in some way special. There should be some semi-official site with a data base of part numbers, names, dates of production, and so on. Dimensions are less important. A tremendous amount of work I suppose. There is Peeron and Brickset, but I find them less easy to use than the BrickLink.

Lego must have such a data base though. And I cannot imagine what harm there would be in publishing it. Anyone bent on producing and selling fakes can already do that. Maybe I am missing something...

[Hey Joe]

Lego does have a database of it, and there's a site called Brickset that has started to incorporate it into their set listings. As far as I know; Brickset lists the parts (with pictures) broken down by set, so that may not be exactly how you would like the data to be presented. Go take a look, it's an all-around excellent Lego resource. This is the page for 10506, and you'll need to click on the 'Parts' tab:

http://www.brickset....il/?set=10506-1

I myself have been a little vocal lately about the overall lack of options regarding Lego track. We've been discussing it over in this thread:

http://www.eurobrick...showtopic=82023

My solution was just to bypass Lego track altogether for my new layout and buy a Chinese knock-off brand. I'm living in China, so it's very reasonably priced. My thread for that is here:

http://www.eurobrick...showtopic=85623

Have fun, Joe

Edited August 25, 2013 by Hey Joe

[StephanSz]

>I went out, spent 25.60 CHF on 10506

You are a die hard duplo train fan :)

I share your conclusion, it must have been a bad mold.

Lego almost got away with it unnoticed!

Thanks for maintaining your very interesting webpage.

[zephyr1934]

I share your conclusion, it must have been a bad mold.

Lego almost got away with it unnoticed!

If it wasn't for you meddling kids!!! (sorry, couldn't resist the scooby doo reference)

[KyleJohnson11]

Kind of off topic, but still under Duplo trains. My wife and I have 2 boys (3 and almost 2), boy #3 coming in November. They love my system trains and do have some Duplo track along with a few push engines. Their big appeal with the System trains is the fact that they move. For Christmas my wife and I are thinking of getting them 10508 Deluxe Train Set (http://brickset.com/detail/?Set=10508-1).

My questions are simple, has anyone purchased this set? If so, how have you and your kids liked it?

Thanks!

Kyle

[Robert Cailliau]

Hi Kyle Johnson,

Yes, I have actually sent this set to a friend for her boy, who is almost 4. He enjoys it very much.

Note two things:

(1) the set allows only an oval, (there are no switches) but there is a bridge and a lot of other stuff.

(2) the loco is of the new type, which no longer stops when it is picked up or falls over or hits an obstacle (zg0 reports above that there were problems with the stop detector, though I have never had any problems with the locos I own)

A few weeks later I sent the same friend the set 10506 which has two switches (points) and more straight rails, and this was a success too as it added a lot more possibilities to play.

Finally, for my granddaughter (now 4 years old) I bought a previous set that was very similar to 10508, when she was 2.5 years old and she loved it. I also bought her quite a few rails on ebay, especially straight ones which are always lacking. All of them arrived in excellent shape.

Be wary though: do not get any of the black ones as those are of a different type and do not mix well with the grey ones.

Edited September 2, 2013 by Robert Cailliau

[zephyr1934]

If your boys like trans and like lego, you can't go wrong with the duplo trains.

PS, and a fun challenge to you is to try to come up with clever builds in duplo... much more challenging than regular lego.

[Tom-Cat]

Hey everyone. I am new here... me and my daughter love the Duplo Trains (ok, it is just me for now since she is only 11 months and mostly watching them go around and destroying the track ;-) ). A friend of mine has a 3D printer and he is printing me some custom tracks... for now we have a nice 90 degree angled cross section done... fits almost perfectly and trains drive over it with ease... here is a little video for everyone interested:

http://www.youtube.com/watch?v=zehIN4Peh68

There is a nice hexagonal cross-section coming up soon and a bridge with a middle section that can be repeated many times to have it at any height you want. :)

[KyleJohnson11]

Thank you for the feedback guys! Now to time the purchase of it correctly.

[micu76]

Hi all.

My Lego Duplo train has some issues with the rotation sensor which is installed on the font wheels' axle.

The purpose of this sensor is to stop the engine when it goes against some obstacle. But in my case, the front wheels' axle someimes doesn't rotate smoothly and locks for a fraction of a second. As a result, the engine frequently and undesiredly stops.

The rotation sensor is implemented through a reed switch plus a magnet on he axle.

I would really like to bypass this sensor, in such a way my Duplo engine never stops.

Can you provide some ideas/suggestions about how to obtain this behavior?

Thanks in advance for your hints!

Regards,

Marco

[zephyr1934]

You might want contact Lego customer service either by phone or by email. If the set is new enough, they will likely replace it for free. Otherwise, they will likely be willing to sell you a replacement part.

[jlehmusk]

Robert, your Lego pages were really interesting to read. Please keep the updates coming.

It does not work with simple graphs, as it is directed. I still have not found a way to get ahead with graphs. I did consult a mathematician on the second problem. He did not get anywhere. However , we agreed (a) it is not a simple problem, (b) I found out it is a property of my algorithm and not at all of the topology or even that it has anything to do with switches. I'll publish on that soon too. I wrote a simple program in LiveCode to do the computation on any matrix, and my algorithm always ends in two steps, no matter which arbitrary set of cells one marks!

The problem can be solved with directed graphs. Each straight section can presented with two nodes. One for each direction of travel. A switch is 6 nodes and 4 edges. It's quite trivial to construct the graph for the whole track from these subgraphs. These examples are refering to figures on your math page:

With this presentation the APR problem becomes SCC (=Strongly Connected Component) problem of directed graph. In APR track there only one SCC. There are many linear time algorithms to count the SCC's. Please see http://en.wikipedia....ected_component for details.

This doesn't exactly solve your problem 2, but it offers an another aproach with a proven linear time sollution.

[jlehmusk]

From what read from the other Duplo train thread I understood that new locomotives don't have the sensor at all. I personally would open and clean it. Some instructions can be found here: http://www.cailliau....in/Locomotives/.

[Robert Cailliau]

Thanks jlemusk:

Robert, your Lego pages were really interesting to read. Please keep the updates coming ....

I'm working on more pages, time always being a problem.

In the meantime I did find the directed graphs, but did not post about it. The general problem is indeed solvable in linera time, my solution works also very well for the particular problem and indeed it does so in linear time as well.

Problem 2 looks close to a solution, I hope to be able to post that soon.

Edited October 18, 2013 by Robert Cailliau

[alainneke]

You're probably correct Robert. It explains the big price jump that zephyr1934 noticed; they were dumping the botched track.

Joe

I recently bought set #10508 for my little daughter (she really likes the bridge!) and noticed that LEGO actually uses both the 'new' and 'old' curves in the same set... You can tell them apart, because:

a) the old ones obviously don't fit next to each other on a plate

b) the old ones still have the 'Duplo' marking on the bottom, whereas the new only have a '© LEGO Group' marking on the bottom

[dhutch]

A friend of mine has a 3D printer and he is printing me some custom tracks... for now we have a nice 90 degree angled cross section done... fits almost perfectly and trains drive over it with ease... here is a little video for everyone interested:

Interesting to see a cross-over made with lego, and then one custom made with a 3D printer. I have just dug out my childhood set (actually a several sets, and extra track) from the attic which will date from early 90's (black track, predating power trains all together) and that includes crossing, standard parts back in the day!

Daniel

[Robert Cailliau]

dhutch is right in a sense: the old black tracks divided the circle in 8, not 12, and had a 90º crossing. These old tracks do fit more or less with the new ones, but their sleepers are not as high and their pins are too low down to avoid getting in the way of knobs on bricks.

I bought a few "half" length straight rails from the old black sets, as a measure to deal with some spaces left in some layouts.

In fact, apart from the standard oval, almost no layouts, even from Lego's own examples, can be built in a strict sense, they need the play in the connections.

Another interesting thing perhaps: with the help of some mathematicians, the second problem of the "all-points-reachable" topic got solved. You can find the proof here:

http://www.cailliau.org/Alphabetical/M/Mathematics/APR/Proof/

Not for the faint-hearted. It transpires that the property of the APR algorithm is more general and not linked to railway problems at all.

[Adam Badura]

Excellent! I'm so happy that I have started this topic! Really interesting things got said/published here!

[Robert Cailliau]

Agreed, thanks Adam.

And happy new year to everyone!

[Tom-Cat]

Hi all.

Here is a bridge made out of normal Duplo bricks with special 3D printed bricks on top to make a proper curve:

http://pc.sux.org/to...rainBridge1.jpg

http://pc.sux.org/to...rainBridge2.jpg

Works really nicely... you can extend the bridge as you want and also curve it if needed :)

Edited January 14, 2014 by Tom-Cat