Steel track construction.

Ok, being an engineer in training, and somewhat bored at the moment, I was thinking about track cross sections, and how there's 2 main flavours. B&M and Intamin style where the side wheels run outside the track and the ties connect inside the track. And then there's Arrow and the oddly similar Vekoma style where the ties connect outside the track, and the side wheels, for god only knows why, run on the inside of the track.

Now I can think of a million and one reasons why the B&M style is prefered:

-It looks better and less shonky looking
-Probably easier to construct
-Can get more out of the same gauge of track. (If you have the Vekoma style, you have to get a lot in that track channel - the wheel assemblys, brake fins and some sort of friction wheel surface. Whereas with the B&M style, you no longer need to have the wheel assemblies inside the channel. And you can have a lot more room for the various things like brake fins.) Notice that the B&M brake fins are really really thick compared to all other coasters. I know that B&M also use their brake fins as couplings, but I reckon that they'll last far longer than other coaster types as they can pack more friction material in the space and that they'll probably be less susceptible to warp than thinner fins.

-This is where I'm starting to leap to conclusions a bit. I reckon that the B&M style is far superior to the vekoma style for maintaining smoothness. I think a combination of the shorter and stiffer ties which don't have hideous right angles in. (which are obviously a problem with the vekoma style in that they seem to weld plates to help deal with the stress in the right angles) The intamin truss style should be pretty good at maintaining smoothness as well.

There are only 2 positives I can possibly see to the Vekoma Style.

1. It should be easier to maintain the main wheels of the coaster, as all that will need to be done is raise them off the track, take the wheel off, put a new one on. On a B&M style track, the side wheel assembly will possibly need removing in order to access the mainwheels.

2. Vekoma must be far far cheaper. B&M looks pretty straightforward, but their box section must be tricky to make. All Vekoma have is a circular spine with identical ties in different positions, but why not have the ties attach to the inside and do that anyway?

Anybody else got any thoughts? I'm dying to know why Vekoma persist with a track cross section that has been used since the arrow corkscrew models. (And how they got away with using the same cross section as arrow)

The Arrow/Vekoma style also has better characteristics in the event of a wheel/axle failure, since the train will tend to drop into the track rather than slide off it. I don't think the design really matters in terms of smoothness. The design of the wheel assemblies is much more crucial.

The shape of the track spine is a totally different issue, and just about every possible combination has been tried over the years, and shouldn't matter in terms of the ride quality. I suspect the reason that B&M use the box section is that a round spine would either be a rather large diameter, or with very long ties.

In terms of ascetics,my personal favorite is probably the old Schwarzkopf box girder - http://rcdb.com/37.htm?p=104

[AyTrane]

The box spine is a lot more ridged than the Arrow spine( which is why Vekoma had to use the double spine for the SLC, and some sit down coasters). With the Arrow "U-bracket" assembly, a lot more can go wrong structurally, and the coasters constantly have to be re-gauged (much like wooden coasters). Think of the bracket as a lever arm, when a train goes around a curve it torques the track away from the spine on the outside rail. The original design for the Arrow track came from what both wood coasters were doing, and how railroads operated. The wheel flanges were on the inside, so this was considered the norm. Back when Arrow built mostly mine trains, this wasn't a problem, as the coaster was supposed to look a certain way, and the brackets were short enough that the stresses from the train wouldn't do much damage to the structure over time. Arrow kept this design similar for all their coasters, but added a spine to re-enforce the track.

Schwarzkopf devised a system for the train to have the wheel assemblies on the outside, so therefor, while traveling around a curve, the train would be pushing in on the spine, rather than pull away from it. This system worked really well, and kept the track in good shape, but the wheel assemblies needed a little more maintenance and had to be redesigned for the larger looping coasters.

Intamin/Giovanola tried Arrow's method (as seen on Vertigorama), but never got the project running. Later, they introduced the box spine to the world. This proved to be a very ridged design, albeit harder to construct, and required very little maintenance. B&M adopted a very similar design when they branched off to form their own company. They re-shaped the cross members and designed new trains.

Intamin later moved on to the truss-work that they are using now. This design was easier to fabricate, and tended to be lighter weight. The track could also be "beefed" up to a 4-rail track in areas, or lightened to a minimalistic 2-rail design.

Arrow and Vekoma have very similar track because they used to collaborate on projects, a lot. Vekoma used to pay licensing for use of the track design. Vekoma was also used as a European parts manufacturer, making it easier for clients to access needed replacement parts. Vekoma has since mostly moved on to a newer outside rail track and train system.

In closing, yes, the B&M/Intamin designs are stronger than the older Arrow designed track. The trains also open themselves up to smoother rides. With newer train designs out there, older Arrow and Vekoma coasters could be a lot more enjoyable, but alas, time takes it toll on everything.

[AyTrane]

And in response to you inquiry about the wheel assemblies and changing wheels. The same process for getting an Arrow wheel off goes for Intamin trains as well. The wheels can come off on the inside for Intamin designs. B&M coasters have a rail-less maintenance track that allows access to the full wheel assembly. All wheels can be changed quite easily on each manufacturer's design.

Awesome cheers, I suspected that repeated stress would start to deform the longer ties. I also kinda wondered about Flashback and Shockwave's track as it's very B&M like, but intamin.

Yeah, I see what you mean, Vekoma have seen the light :p http://www.vekoma.com/images/stories/mk ... lowres.jpg
http://www.vekoma.com/images/stories/mk ... lowres.jpg

(wish they'd do more custom tracks though)

[AyTrane]

Vekoma has not only re-done the entire way they design coasters (making them smoother and more enjoyable), they have also completely redesigned the trains for the new coasters making them properly trailered and more comfortable. The wheel assembly no longer leads the car but is rather lead by the car in front of it, making transitions much smoother. I could see the newer train design (2 abreast) being implemented on the older designs, bringing new life into them.

I would love to see a cross between the new Vekoma restraint system, and these trains (as they are properly trailered). I'm not a big fan of the lack of padding on the restraints on this model.

Those trains aren't actually Vekoma, they were made by a 3rd party company. They also made the trains on this.

[AyTrane]

I didn't say they were. I said I would like to see Vekoma's restraints put on them.

Originally posted by AyTrane

Vekoma has not only re-done the entire way they design coasters (making them smoother and more enjoyable), they have also completely redesigned the trains for the new coasters making them properly trailered and more comfortable. The wheel assembly no longer leads the car but is rather lead by the car in front of it, making transitions much smoother. I could see the newer train design (2 abreast) being implemented on the older designs, bringing new life into them.

I dont get what you mean by the leading car thing. but is this counter the reason why vekoma slcs have some daft thing trailing the rear car?

Originally posted by blythy

Originally posted by AyTrane

Vekoma has not only re-done the entire way they design coasters (making them smoother and more enjoyable), they have also completely redesigned the trains for the new coasters making them properly trailered and more comfortable. The wheel assembly no longer leads the car but is rather lead by the car in front of it, making transitions much smoother. I could see the newer train design (2 abreast) being implemented on the older designs, bringing new life into them.

I dont get what you mean by the leading car thing. but is this counter the reason why vekoma slcs have some daft thing trailing the rear car?

On Vekoma and Arrow coasters, the back of each car is held up by the car behind it, that's why they have the weird wheel assembly behind the last car. On most other coasters the front of each car is held up by the car in front of it. Recently, Vekoma has switched to the latter style to improve the quality of their rides.

Originally posted by AyTrane

I'm not a big fan of the lack of padding on the restraints on this model.

Actually, when I rode it, the lack of padding was completely unnoticable...
Those restraints are by far the most comfortable restraints I've ever experienced. The butterfly thingy doesn't really touch your thighs (well, it's not really pushing down onto them...), you are mostly being held in the seat with the flat part pushed onto your stomach. It's a really interesting restraint design, which allows for complete freedom. I loved going through the cobra roll without any OTSRs!

Originally posted by Kennyweird

On Vekoma and Arrow coasters, the back of each car is held up by the car behind it, that's why they have the weird wheel assembly behind the last car. On most other coasters the front of each car is held up by the car in front of it. Recently, Vekoma has switched to the latter style to improve the quality of their rides.

I get you, cheers

have to agree with Vid, the cars on the Wiener Prater Boomerang are amazingly comfortable and it really adds to the ride experience that they are not ots restraints.

But this ots restraint thinghy raises some questions with me and since this is more of a technical topic I think I can ask them here and get a proper answer. So why does Intamin those ots LAP BARS? Isn't that completely useless. I rode Desert Race at Heide Park and the ride was smooth as hell but it was also unneccesery uncomfortable becouse with your neck you were constantly jammed into this steelwork which covers your shoulder. Is there somekind of mechanical explanation to why Intamin produces its seats like that??

In addition I\d like to add that I don't think this arrow/vekoma track style has an effect on smoothness of the ride, but more the track shaping, for instance that vekoma still does'nt know how to properly bank a lead in to a corkscrew. Like on the Walibi World Xpress or RNRC's the entire track is extremely smooth and heartlined but where it fails in my opinion is at the entrance of the cork at the end. So it has a lot more to do with shaping of the track then the design of the actual track itself. Also newer generations Vekoma coasters: Kumali for instance, have the same track as SLC's before but different shaping and re-designed wheel axles.

And the whole new Vekoma style (battlestar Galactica is just like B&M track only with, as mentioned before to be unpractical, a round spine.

Vekoma has been using that style for a while...on the motorbike coasters for instance.

not with a spine this thick

[AyTrane]

That track looks more like suspended track.

Over the Shoulder Restraints are mostly for insurance and liability reasons. It's the reason that Kingda Ka has the Over the Shoulder lap bars and Top Thrill Dragster doesn't; the reason that Revolution had to have Lap Bars and high seat backs added; as well as a lot of wooden coasters having the head rests. If parks and manufacturers didn't have to worry about being sued, you would see a lot less overbearing restraint systems in place (not necessarily unsafe, but less constricting).