Bachmann Online Forum

Discussion Boards => HO => Topic started by: Jay on August 10, 2007, 02:29:19 PM

Title: Curved Bridge
Post by: Jay on August 10, 2007, 02:29:19 PM
I have a small river that I need to gap.  I have a Wye that curves over this river for about 10 inches.  Any suggestions on a bridge?  Thanks
Title: Re: Curved Bridge
Post by: Jake on August 10, 2007, 02:41:25 PM
Believe it or not, curved bridges were actually "curved!" They were made up of multiple straight section on which the curved track was lain. But then again, trestles (by that I mean the bent structure trestles) do follow the curvature of the track. The CMR team (www.cmrtrain.com) does custom laser cut kits, maybe drop them a holler.
Title: Re: Curved Bridge
Post by: SteamGene on August 12, 2007, 08:03:16 AM
Jake, you left out a "not." 
I'm currently building a Micro-Engineers steel viaduct bridge.  It's quite a project, but the end results should be fantastic.  Check them out in the Walthers catalog.
Gene
Title: Re: Curved Bridge
Post by: ebtnut on August 12, 2007, 11:39:06 AM
In general, any railroad bridge built before about 1980 was not curved--it was a series of straight sections joined together.  Now, the ties laid on top would follow the curve of the track, giving the appearance to the casual observer that it was "curved".  The advent of computers has led to the successful design of curved bridges, because the programs could compute the odd stresses introduced by the curved members.
Title: Re: Curved Bridge
Post by: rollerbearing on August 12, 2007, 11:49:39 PM
What about that long curved bridge owned by the IC.
Title: Re: Curved Bridge
Post by: Jay on August 13, 2007, 01:07:32 PM
This has been great information from all.  Thanks!  I am looking into the curved bridge recommended by Gene and see if this will work for my application.
Title: Re: Curved Bridge
Post by: SteamGene on August 13, 2007, 03:32:49 PM
Jay, do be prepared for a lot of work.  A lot.  Did I mention the kit has a lot of pieces and may of them are small? 
Gene
Title: Re: Curved Bridge
Post by: Jay on August 13, 2007, 03:54:21 PM
Thanks Gene,

I will keep it in mind.  I am just beginning the research process for this bridge and have many other projects that are in line ahead of this.  But you have given me a place to begin.
Title: Re: Curved Bridge
Post by: SteamGene on August 13, 2007, 04:02:40 PM
One of the German model companines like Heljin has a curved stone bridge, but it apparently has only one radius, listed in cm and I was just too lazy to convert cm to inches.   It appeared much to tight for my needs and the Micro-engineering one can be built as tight as 18 - all the way to straight.
The sub-assembly that took me 45 minutes to put together yesterday only took about five a few minutes ago.  Only ten more to go.  ;D
Gene
Title: Re: Curved Bridge
Post by: Jay on August 13, 2007, 04:24:32 PM
What is the length of your curve to be?  After looking at the bridge I think it may be a bit more than I need in that area.
Title: Re: Curved Bridge
Post by: SteamGene on August 13, 2007, 04:40:37 PM
The bridge is 150 feet, which comes to a bit over 20.5" on the layout.  Some of their others might work better for you, if you can get them to curve.  Call and ask - they don't have a website or e-mail.
Gene