Dragster Question

Ok, so I was browsing the recent post about favortie coaster picture, and I came across this dragster pic. http://www.rcdb.com/installationgallery1896.htm?Picture=29

Look closely (sp?) at the track top. Why is there a notch in the track? Is it on every piece of the track, or just at the top? Ive never noticed it before, and im quite curious.

Im thinking its something technical, like maybe there is a piece on the trains that wasnt measured right, and they had to notch it? But thinking about it now, i doubt it.

Josh

That's a designed feature, it wasn't added as an afterthought. If you look on any quick transition of Intamin track, you'll find these "notches" because the large steel beam (not sure of the technical term) under the center of the cars would make contact with the track when the train negotiates the transition. It's kind of hard to explain, I'm sure somebody else could do a better job of it.

Oh, funny, I never thought about that....

Thats very logical, and I was just about to say, yeah, but Storm Runner doesnt have that! But, I just found one picture, and clearly, it does. Wouldnt you think that they would raise the cars to prevent that? It just seems to me like it would be less manufacturing work if they didnt have to cut out that notch, and just put a riser on the cars. But what do I know, I dont work for intamin or anything.

Any other thoughts?

Josh

Just a thought, but the further off of the track the car is, the more -g's you'll experience as you go over the apex of the top hat. In order to keep the g's down (or up i guess), the train is kept as close to the track as possible.

You would also have to deal with the cars of the train being too close to each other while 'bending' up (ie: going into a hill and coming out of a hill), and further apart when 'bending' down (ie: going over the top of a hill). If you were to raise the height of the trains, you'd also have to space them further apart and design a better connection between the cars.

Also, the break mechanism is on the bottom of the car. If you raised the car, you'd also have to raise the break fins both at the rollback section and at the break run section (in the case of dragster at least)

*** Edited 9/15/2004 11:51:07 PM UTC by Kaldaim***

does anyone know what that I-beam looking piece of metal is at the top right hand corner

Kaldaim, I think you have the right idea on the distance the cars are from the track. I remember seeing something about the difference in Arrow/Vekoma vs. Intamin/B&M in smoothness, and it all had to do with the position of the riders in the elements. If you were to raise the rider up farther the ride would be rougher through the transitions, and Intamin coasters would be no better (smoother) than Arrows creations.

The I-beam is for the stairs/walkway that go over the top. Wicked Twister has that same notch in the track, it's just a little extra clearance I'd guess.

I figured the I-beam was where the attendant sat and told everyone to stay seated as they went over the top... ;)

Turbo, that is part of the walkway which wasn't yet finished in that photo.

The notch was clearance for the catch dog that hooked onto the launch sled.

I noticed the notch as well on Millennium Force. You can see it on top of the two hills that go onto the island. I have been wondering what those were.

-Sean

Im not sure what im looking at, is it the rope(I doubt it) where is the notch.

---

CoasterToCoaster said:
I figured the I-beam was where the attendant sat and told everyone to stay seated as they went over the top...

---

haha, i want that job!

WILLDOG--take a look at the picture provided in the first post in this thread. They're all referring to the notch in the center of the track crossbeams. *** Edited 9/18/2004 5:49:29 PM UTC by PhantomTails***

The interesting thing is that the most logical part they would be trying to avoid catching with that notch would be the launch dog just ahead of the fourth axle.

What makes that interesting is that the dog is fully retracted at that point on the ride...that is, there are no protrusions below the car center beam. You can see this when the train is sitting in the pre-launch staging area, with the dog retracted.

I wonder if there is a risk of the car chassis snagging on a track-tie if that notch is not there, perhaps the tip of the nose or the back of the last car...

--Dave Althoff, Jr.

How does the dog retract/extend?

The catch car dog is an electro-mechanical system. Just before the axle of the 3rd car, there is a cylinder on the underside of the car on either side. Inside these cylinders is a permanent magnet with a coil of wire around it. That magnet attracts the catch car dog and holds it in its retracted position. At the start of the launch block, there are 2 black strips on top of the catch car track. When the launch operator presses the launch buttons, a current is sent from those strips to the wire coils around the magnets. This creates a magnetic field that opposes the permanent magnet and allows the catch car dog to drop under its own weight. At the same time the train rolls back to engage the catch car. From this point until the end of the launch, friction holds the catch car dog in place. At the end of the launch, when the catch car enters its brakes and the train out runs it, the catch car dog is reattracted by the permanent magnets in the cylinders to its retracted position because there is no longer a current traveling through the wire coils.

Wow. That's pretty sexy. Thanks PUE.

But doesn't the solenoid have to have a changing flux in order to generate magnetic force? Does the current just continually ramp up until the dog is locked in place on the catch car?

I have replied to this topic before, and I don't see the notch, someone please show me which picture to look at, and wher is the notch

http://www.rcdb.com/ig1896.htm?picture=29

There are notches in the horizonal ties connecting the two rails.