# Building "Access" Bridges?



## noela (May 22, 2008)

I am getting set to build a couple of "access" bridges over portions of my layout. I have done some research, but would like to hear from anybody that has actually done so.
I don't want huge bridges, but I figured that 30" wide would be enough. I was also planning on having stairs as they would allow the best access to get to the bridge. Topography makes it virtually impossible to make a ramp for access, as the incline would have to be greater than 45 degrees. Sadly, I must say that my layout is not wheelchair friendly due to trees, wet terrain, and uneven ground. People with limited ambulatory situations can run, but they just can't follow the trains they are using.
At present I can walk around the entire outside of the layout, and can get into the lower loop area because the track is elevated more than 5' so I built a doorway. The middle loop is the problem, and I need to build a bridge that will go up from an area that is roughly 2 1/2' below the top of the track, over one section of the layout, allow access to that section of the layout, which is about 3' below track level, and to continue over another section of the layout and end with steps to that area, about 4' below the level of the track. I was planning on making the bottom of the bridge 10" above the top of the rail. The total length of the bridge would be around 14'.
My plan would call for using "Dek Blocks" (if you notice in my picture posted on another forum board, this is how the entire layout was built), to support 4 X 4's, and using 2X8's between them, and topping the bridge with 5/4's X 6" P/T wood. I would probably have to create my own step risers due to the terrain. Needless to say, this will involve a lot of work and expense, and if there's an easier way to do this, I am open to suggestions, any direction or help is greatly appreciated.
Thank you.


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## peter bunce (Dec 29, 2007)

Hi, 

I have all 2 (& 1 to build) of my bridges removable - using Hillman bridge clamps the 'click in' to position but are instantly removable. Get the size to suit your rial, either code 332 or 250. 

Fix the track at the point for the bridge add the bridge clamp ensuring the track is long enough on the bridge and position the second clamp. Add the bridge and the can be removed. another suggestion is to use instead the bridge hinge clamps that will allow the bridge to hinge like a bascule (lifting) bridge. 

Here is the second one - this came as a kit from Germany and is just under 4 foot long - the track extends each side of the bridge and this allows for the bridge clamps top be well outside the actual bridge. I use Peco track code 250 track.i



















And here is a much more new shot as the bridge has had the track laid and this how the clamps and their location with regard to the end of the abutment - the bridge drops in at the outer edge of the white strip.The track is fixed with the two wall plugs that can also be seen. I added a couple of styrne card strips (in white) to align the bridge better - on the outer side of the track are a couple of tiny spring loaded plungers that can be adjusted to fir your track, the bridge clicks in with these, mine needed some adjustment hence the bits though the plunger unity is adjustable with as mall screwdriver and some oil to free it off a bit - its very tight!

l


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## noela (May 22, 2008)

Thank you so much, it looks great. My problem is that the layout is built over very uneven terrain, and most of it is 4 track. It is built like a 2 1/2' wide deck, with support posts every 5'. I did consider this approach, but the "take-outs" would have been very heavy, so my only alternative is to go over. I am going to try and post the pix from another of my forum posts, which illustrates the construction, and my "problem". Can't post the pix, but it is posted in another topic "Cleaning blossoms and Twigs".
Thank you again.


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## peter bunce (Dec 29, 2007)

Hi,

No Need to post it again (are you a 1st class member by the way?) IF not that could be why you can't post - a way round that is to post from a photo hosting site 

But for now here is a link to the post with the photo for you http://www.mylargescale.com/Communi...64234[/url The photo is the 3rd post down. 

Now having found it you have a problem there - you have 5 feet between posts you say, that will allow for a lifting on a pivot at one end bridge perhaps? The pivot is close to the posts to stop twist and the lifting portion drops onto a substantial ledge (or abutment) Current can be kept complete by possibly brass strips or 4 sets of clamps - once they are located there should be no maintainance as they do not need it, I add some vaseline occasionally, on a set I have been using for years. The trick is solid locations of the track. 

Add some sides that would allow for an easy location for a handle to pull it up?

An altentative, is a turntable style bridge, with a ball bearing off center pivot, sat on its own post perhaps?


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## denray (Jan 5, 2008)

These are two pictures of lift bridge I built for the clubs portable layout, this is something we will lift 20-50 times aday with no trouble of aligning back everytime. With the tapered round pin it aligns everytime, the collar is a 3/4" shaft collar found at graingers or Mcmaster Carr or some farm stores. I took a 3/4" shaft and turned down on a lathe. You could use a belt sander if your careful to keep it as even as you can, this tapered is on both sides.
Dennis


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## noela (May 22, 2008)

WOW!!!!


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