Tomytec Bm04 Moving Bus Minimum Radius

[Robsr]

Ive tried searching on here for my answer but I got 1000’s of unrelated answers to my question.

I’ve just managed to source two of the Tomytec moving bus system twin liner (bendy bus) starter sets. 
I’m planning to make my own roads on my layout and have seen how to make them but can anyone tell me the minimum radius that a bendy bus and a Bm04 unit can make please? 
I know they make a 66mm radius curve but is that the absolute minimum that a bus can handle?

Thanks in advance. 

[mr bachmann]

The bendy bus set comes with 177 - 30 , the bus will do 140 Mm , going tighter will be trial and error , 

the new realises button cell chassis copes with the tight corners , I am using Tomix track , but if you are 

constructing your own roads make the road wider to keep the rear wheels from falling in the ‘ditch’ .

 

also did you know the bus track and tram track from Tomix can be clipped together for inside/outside road/tram

roads , and Tomix train track joins the tram track .

[cteno4]

If you are making your own wire guideway you can experiment with more complex curves that follow more the usual path a bus uses to steer a corner, I played a lot with the old faller and first series of 2 axle Tomytec busses with this. You can get it to go around a pretty tight street corner if you swing the bus out to the middle of the road before the hard turn that goes into the middle of the intersecting road and then gradually correcting back into the lane. For tests I just taped my wire onto the back of a thin sheet of stiff cardboard or 020 styrene to try different patterns to see what worked reliably. Once something works well it can be copied onto the bottom of your street surface and wire glued down to it.

 

i expect the articulated bus has its own likes and dislikes for curve geometries than the 2 axle. But it makes for much more interesting scenes than a big curved circular radius of the Tomix bus track.

 

jeff

[mr bachmann]

Also under Tomix tram track are groves (both straight and diagonal) that steel wire can be clipped into to enable the bus to run on with the tram .

 

[Robsr]

18 hours ago, mr bachmann said:

The bendy bus set comes with 177 - 30 , the bus will do 140 Mm , going tighter will be trial and error , 

the new realises button cell chassis copes with the tight corners , I am using Tomix track , but if you are 

constructing your own roads make the road wider to keep the rear wheels from falling in the ‘ditch’ .

 

also did you know the bus track and tram track from Tomix can be clipped together for inside/outside road/tram

roads , and Tomix train track joins the tram track .

I’ll be making my own roads so the Tomix roadway will be redundant. I noticed that they go as tight as 66mm radius for rigid chassis but just wondered what the bendy bus could handle. I’ve seen a few videos about making room for the rear axles on both types as that makes sense as I’m a lorry / van driver anyway. 
Thanks for your input 

[Robsr]

18 hours ago, cteno4 said:

If you are making your own wire guideway you can experiment with more complex curves that follow more the usual path a bus uses to steer a corner, I played a lot with the old faller and first series of 2 axle Tomytec busses with this. You can get it to go around a pretty tight street corner if you swing the bus out to the middle of the road before the hard turn that goes into the middle of the intersecting road and then gradually correcting back into the lane. For tests I just taped my wire onto the back of a thin sheet of stiff cardboard or 020 styrene to try different patterns to see what worked reliably. Once something works well it can be copied onto the bottom of your street surface and wire glued down to it.

 

i expect the articulated bus has its own likes and dislikes for curve geometries than the 2 axle. But it makes for much more interesting scenes than a big curved circular radius of the Tomix bus track.

 

jeff

Thanks for your input.

I will be making my own roads and have watched a few videos about thickness and depth of wire but haven’t seen any about turns. 
I’m going to experiment with turns but wanted a heads up beforehand to save time setting something up that won’t work. 

[cteno4]

It’s super fast to just draw out something on some thin chipboard and tape the wire down to your layout and let it run. Some simple trial and error quickly let me see what could and could not be done and ways to make turns look nicer. Of course if you are going to add any changes in elevation on the street I would definitely mock that up to test it out. You can just cut out a rough street idea in thin chipboard and then prop it up with cardboard pieces and tape or hot glue it all up to hold down into your vertical contours. It’s very fun to get out of the tomix bus loop configuration, but it does need some testing to see what will work and what won’t.

 

I found some floral wire that seemed to work best. Have to take a magnet to the store and see which wire have a good iron core. The faller wire had no paint coating and arrived pretty rusted up, so I liked the thin green paint coating on the floral wire I found, and it worked as well as the faller wire.

 

I never ended up doing anything with it as no room on our club layout for it in the end and then we moved to Ttrak and there it’s very tight on space. But I did feel doing either a straight city street and hiding turn arounds at each end was the best idea probably. I was able to do a pretty tight reversing loop if I did the right easements. You can then loop it back onto the other side of the street for the return. This way you could spread out multiple busses on one loop and they just keep cycling around to each side of the street. You can also gap the track right on the Y fork of the loop so the bus goes onto the one side and returns across the gap on the other if you just want the bus traveling on the same center path like on a narrow rural road scene. It’s having the space to hide the loop backs that is the hard part.

 

I experimented doing the roads with 040 styrene sheet and routing a channel on my path for the wire that was just over the thickness of my wire. The  glue wire into the channel and cover this with a printed streets out of paper. This gave very good steering magnet tracking even with the old faller bus with a much weaker steering magnet. It might be just as easy as cut the path all the way thru the stryene and just gap it the width fo the wire and lay it in, I didn’t get to that point of experiment, but the router worked and just had to keep it all flat while routing the wire path. The faller method of trying to rout out a channel from a plaster street or embed it into the plaster directly is fraught with issues to keep the wire and a constant dept and streets clear of any tiny wheel hang ups. Paper streets are a lot smoother and easier to deal with and lets you do a lot of road markings and details on the computer and you can even do street wear and stains in the graphic program or come bad and add them with more traditional weathering.

 

You can also do the bus pull ins and bus pauses, just placing small electro magnets or movable permanent magnets under the road. I also did a point/switch boy sliding the blade wire back and forth for a different path or bus pull ins. For a merge you don’t need a movable blade just a small gap and the bus will jump the gap and pick up the new wire.

 

I even got the bus to cross tracks pretty reliably. You need your street right at rail head height and your center piece of roadway in the track needs to fill in as much as your flanges will allow. Get a little bump but it would go across well. If memory serves me right it was a pice of 1/4” 060 strip stock with a bit of paper streets on top that worked just right in my playing around. There are some videos of Japanese setups with crossings like this. You can get fancy and do the full arduino co tool of crossing gates and signals along with a pause electro magnets under for the bus.

 

it was quite fun and educational messing around with the bus for a few evenings. Someday I’ll find a place to be able to incorporate it.

 

jeff

[Robsr]

Thanks for the advice Jeff. The videos I’ve watched have done virtually the same. 
I’m looking at making my roadways out of MDF and routing out a channel to put 1mm music wire into and then putting a card or plastic road surface on top.

I’m thinking of having a few buses on opposing loops line in real life as well as a couple of bendy buses on a one way loop.

I’ve looked at a couple of videos that make a crossing over a railway track and feel confident that I can make it happen as I’ve got a friend who works in electronics who has said the level crossing can be connected to the roadway to stop a bus when the barrier is down.

He’s also said that it would be possible to make a block system that stops the buses from catching up with each other. 

[cteno4]

I liked the pretty soft coated iron wire as it was super easy to bend into place as needed. It was also highly magnetic not being a fancy alloy. Depending on the music wire they can also be hard to bend, they are made with alloys to stay straight in pianos. Super nice wire, but don’t like bending much. May not be much of an issue with the channel holding it all in place. I’ve not tested the my piano wires I have to see how magnetic they are. Have you played with it yet?

 

Yes the crossover works pretty well. Only caveat is you need to have the path perfectly perpendicular to the rail as some angle and one front wheel hits the flangeway first and can knock the bus off the wire.

 

Yep not super hard to have a arduino fire crossing gates and sounds as well as pause the bus when train approaches and back it all out once past. Have you seen Marc’s excellent bus control system he did? Very nice and pauses busses where needed. He is very active on the forum and very informative.

 

https://shin-yukari.weebly.com

 

keep us up on what you do, always great to see other’s ideas and results.

 

cheers!

 

jeff

[Kamome]

The BM-04 doesn’t support 66mm radius curves according to the Tomytec website, along with the intersection pieces. Think I have one of the older BM-03 fitted to a longer wheelbase tour coach but could be wrong on the chassis number. Anyway it struggles with tight curves unlike the chassis that came with original Set A and B3.

 

Definitely need to do some extended testing for your own designs as even the RTR Tomytec tracks are not without occasional issues. Thin plasticard is properly a good way to go for road surfaces. There are a few videos on Youtube, mostly Japanese, although none I’ve seen were using the bendy bus. 

[Robsr]

15 hours ago, cteno4 said:

I liked the pretty soft coated iron wire as it was super easy to bend into place as needed. It was also highly magnetic not being a fancy alloy. Depending on the music wire they can also be hard to bend, they are made with alloys to stay straight in pianos. Super nice wire, but don’t like bending much. May not be much of an issue with the channel holding it all in place. I’ve not tested the my piano wires I have to see how magnetic they are. Have you played with it yet?

 

Yes the crossover works pretty well. Only caveat is you need to have the path perfectly perpendicular to the rail as some angle and one front wheel hits the flangeway first and can knock the bus off the wire.

 

Yep not super hard to have a arduino fire crossing gates and sounds as well as pause the bus when train approaches and back it all out once past. Have you seen Marc’s excellent bus control system he did? Very nice and pauses busses where needed. He is very active on the forum and very informative.

 

https://shin-yukari.weebly.com

 

keep us up on what you do, always great to see other’s ideas and results.

 

cheers!

 

jeff

I’ve only said about using music wire as two of the videos used it but I’m open to suggestions. 
That layout looks amazing 

[Robsr]

14 hours ago, Kamome said:

The BM-04 doesn’t support 66mm radius curves according to the Tomytec website, along with the intersection pieces. Think I have one of the older BM-03 fitted to a longer wheelbase tour coach but could be wrong on the chassis number. Anyway it struggles with tight curves unlike the chassis that came with original Set A and B3.

 

Definitely need to do some extended testing for your own designs as even the RTR Tomytec tracks are not without occasional issues. Thin plasticard is properly a good way to go for road surfaces. There are a few videos on Youtube, mostly Japanese, although none I’ve seen were using the bendy bus. 

Thanks for the info. I was going to experiment with the system to see just how tight both chassis can turn. If necessary I’ll have to make the swing out and back on the corners a bit more than in real life but it’s only me that I’m pleasing anyway. 

[cteno4]

Yes doing easements really helped get things very tight with the 2 axle busses. They like smooth changes, harder ones are where they go astray.

 

jeff

[Madsing]

I have tested the new BM-04 on my layout and unfortunately they don’t work. They simply do not follow the guide wire. I have not (yet) investigated further, but this suggests that the magnet on the BM-04 is less strong (than on the older BM-01~03).

Marc

 

[Robsr]

Do you mean that it doesn’t work on the Tomix roadway or have you made your own roads? 

[Madsing]

Sorry, that was not clear. 
The BM-04 do not work on my own roads.  I have built roads and bus stops on the Yukari layout. They have been fine tuned (material and diameter of the guide wire, thickness of the styrene road) to work with the BM-01~03, but unfortunately they don’t work with the BM-04. 
Marc

 

[Robsr]

Ok, thanks for clearing that up.