Is 90 Degrees possible on wood support structure?

Saturday, September 24, 2005 3:58 PM
Good afternoon,

I was wondeirng if any of you engineering students or fellow enthuiasts think that is is possible to make a 90 degree banked wooden coaster with the structure made out of wood like a GCI , versus the steel structure used bye S&S and TGG. Also since The voyager is going to have 90 degree sections, do you think they will have to support with something stronger then just the normal suport ties to brace the track. I was just thinkin that is posbible, but the track might be ripped up over time if is not supported strong enough. I mean i realize they were able to do it with hades, but they aslo supported that section of track against a concrete tunnell. So well see.

thank you for your time.

Saturday, September 24, 2005 4:13 PM
The one 90* banked turn on Voyage IS in a tunnel. The other will be outside from what I understand. It is a steel support woodie, so it really wouldn't need the extra support. The banked turn lasts about 2 seconds. It's isn't going to rip up track as much as people think.

As for a 90* banked turn on a total woodie as in GCI, I don't see why that wouldn't be possible. Coaster designers have the technology to do it. Why not. It is a great element!


Saturday, September 24, 2005 5:20 PM
Definitely possible. There's nothing that makes the 80+ degree turns on Thunderhead easier than a 90 degree turn. The real question is would it be fun and would anyone want one?
Saturday, September 24, 2005 5:38 PM
Going off that same question --> would an 85-90 degree drop be feasible on a woodie?
Saturday, September 24, 2005 5:39 PM
Everything is possible.


...keep in mind these turns are mathematically designed not only in degrees, but even in minutes. It's not that simple to make a turn 90° instead of 82° for example...

Wood or steel doesn't make any difference, wood is just harder to work with it. A much greater challenge to calculate the perfect structure.

Saturday, September 24, 2005 6:14 PM

coasterMNguy... said:
Going off that same question --> would an 85-90 degree drop be feasible on a woodie?

SFGADv woody will probably be the first or very very close to it *** Edited 9/24/2005 10:15:40 PM UTC by westcoaster man***

Saturday, September 24, 2005 6:19 PM
Doesn't Hades have a 90 degree turn?
Saturday, September 24, 2005 6:27 PM
Yes, Hades has a 90* banked turn in a black tunnel.

As for steepness of a drop, why couldn't a wooden do it? Right now, Voyage would take it as a woodie with 66*. But there isn't a reason it couldn't go steeper. If a steel can do it, they can certainely develop the technology to make a woodie do it.


Saturday, September 24, 2005 8:29 PM
Correction: The Voyage's two 90-degree banked curves are not in tunnels.


Saturday, September 24, 2005 8:40 PM
Wow, Paula, I am sorry, I thought one was in a tunnel and one wasn't. Thank you for the correction.

Katie, who can't wait to give Holiday World her business next year.

P.S. Paula, my friend Kelly said he had a lovely time on Friday.

Saturday, September 24, 2005 8:41 PM

CoastinKatie said:
Right now, Voyage would take it as a woodie with 66*.

Everybody forgets about Balder's 70* drop. ;)

Raven Maven said:
Correction: The Voyage's two 90-degree banked curves are not in tunnels.

Yeah, if I remember correctly the first one is at the far turnaround, and the other one is just after the triple-down tunnel.

Saturday, September 24, 2005 9:34 PM
Surprised that no one has mentioned that the structure for Hades' 90 deg bank is really the concrete wall of the tunnel. There's one for you, wood track with a concrete structure. Actually I think that's true in a few other tunnels.

I'm sure that you can do a 90 degree bank with a wood structure. The real issue structurally isn't the steepness of the bank, but how large the lateral forces are, and how far above the ground the track is where the lateral forces are applied. Dealing with a lateral force 10 feet off the ground is much easier than dealing with the same force 100 feet off the ground.

Saturday, September 24, 2005 10:03 PM

CoastinKatie said: I thought one was in a tunnel and one wasn't.

Not a problem. It's hard to keep everything straight with that coaster!

Chad from Gravity Group was laughing with us today...that often the enthusiasts know the layout of a coaster even more than the designers!

It was good to see Kelly again yesterday, too. Still can't believe the 90+ temps we're still sweating through!

Next time I'm down at the construction site with a camera, I'll go back behind the 90-degree banked curve and will snap a few for the HoliBlog.

Night all! Paula

Sunday, September 25, 2005 12:58 AM
90* temps, 90* coasters, Wow, it's hot enough for Splashin Safari to be open till Oct.
Sunday, September 25, 2005 1:16 AM
90-degree banking shouldn't be difficult with any form of structure simply because the forces are still directed perpendicular to the track, so a conventional bracing method can be used, it just gets a little tricky. It's still a matter of redirecting force into the footers.

A 90-degree drop, though, I'd think would be a little more difficult because as the drop gets steeper, you start to run out of places to support the track. I'm sure it could be done, but it could be a little bit tricky to keep the track well supported to keep it from literally falling down on the structure. The whole 90-degree section would be sitting on a single footer, and it might be necessary to brace it "above" as well as below.

But what do I know? I'm not an engineer of any kind....

--Dave Althoff, Jr.

Sunday, September 25, 2005 2:23 AM

it might be necessary to brace it "above"

Yay! Headchopper.

Sunday, September 25, 2005 2:20 PM
The real problem with a 90 degree drop is more handling the forces on the riders than the structure. The restrictions of wood track would make it more difficult than with steel. The other problem would be the difficulty of doing daily inspections on the vertical track.

I am certain thought that it would be easier to design the structure in steel than in wood. Wood is best used in compression rather than tension, and a vertical drop would be easier to support if at least some of the structure is in tension.

Sunday, September 25, 2005 3:18 PM
While we are talking 90 degree banks, what about overbanking? My non educated opinion says yes, but only with a steel support system.
Monday, September 26, 2005 9:25 AM
...for exactly the reasons Jim Fisher mentioned. That's kind of what I was getting at in talking about the problems of supporting a 90-degree drop, but when I wrote it I couldn't come up with the words "compression" and "tension". I keep telling you people I'm not an engineer! Thanks, Jim! :)

When you are talking about banking, the real limiting factor is the mechanics of the train, and the roll rates that allows. If you are talking about a PTC train, for instance, the rear axle can swing a whopping three degrees. That means that your maximum roll rate is limited to three degrees within the length of the wheelbase, which is..what, about six feet for a 2-bench train? Three degrees in six linear feet, that means 30 minutes per running foot maximum roll. That means you need 180 feet of track to lead into a 90-degree banked curve.

Getting back to support that I think of it, there is a tried and true method for supporting wood coasters in tension, commonly used for the now-rare high turnarounds found on classic wood coasters: Those were typically cable-stayed to supply support in tension and reduce the amount of structure needed on the outside of the curve.....

--Dave Althoff, Jr.

Monday, September 26, 2005 4:20 PM
You would pretty much have to brace the 90 degree turn on the outside, since the train is on the inside... Cables would want to pass through where the train rides. I suppose you could extend the support structure above the track and attach the cables there, which would also make some neat headchoppers...

You must be logged in to post

POP Forums - ©2018, POP World Media, LLC