Atlas Bridge

[phillyreading]

Has any one installed an Atlas bridge to lift up? The bridge in question has; a 40 inch base, made of plastic, one & a half inch thick on the ends, has Atlas solid rail(three rail track).

What I want to do is help a friend of mine install an Atlas bridge but not sure how to raise it up. He wants to use a heavy string or small rope attached to the one end with pulleys, but there is more to it then that, he doesn't want to cieling mount any pullies, so I am don't how to procede. In my opion he wants to do something that I am not sure if it will work. He wants to attach a small string to the end of the bridge and bring it up to the top of the plastic supports on the bridge and lift the bridge some way from there, also he wants to use counter balance weights. The work space we have is about 36 inches wide by six feet high if we need the height.

Any help would be appriciated.

Lee F.

[Anonymous]

Lee,
I think this could be done, but describing it would be difficult.

I wouldn't use wire or anything like that. I would put the bridge on a scale and get the weight. Then divide that in half, this is how much weight you will want UNDER the pivot side of the bridge.

You will need a locking mechanism to lock the non-pivot side of the bridge.

You will need, most likely, a 1/2 inch threaded steel rod for the pivot. This is due to the weight of the bridge and for stability.

To procede I would mock this up OFF the benchwork, then insert the whole thing into the bench work.

Drill 1/2" hole through the benchwork mount, through the metal bridge supports for the bridge (there are metal plates that run the length of the bridge inside the plastic plates under the bridge). These hole MUST matchup 100% or the bridge will bind and break. Thread the 1/2" threaded steel rod through the benchwork mount holes and holes in the bridge. Then put 2 washers on each side between the bridge and benchwork, and one washer on the outside of the benchwork mount, then secure with a lock washer and nut. Then attach the counter weight under the bridge.

Hopefully I described this well?

You need to ensure that the bridge's trusses do not bang onto the layout. If you could make your approach so that the approach can fit into the opening between the trusses you should be able to open the bridge to full vertical.

Your friend's idea of running the wire along the top of the truss will cause the plastic trusses to break. If he really wants to do something like that he should look at one of the all metal 100 Year Bridge company's bridges.

With my method all he has to do is put his hand under the non-pivot side and lift. If you don't want to drill through the bridge, then you need to find a way to secure the pivot end of the bridge to the pivot.

[Anonymous]

Lee,
Sent you an email too.

[lionelsoni]

I'm guessing that this is the 6920 or 6921 bridge.

I believe that you will find, if you put a pivot below the height of the railheads, the rails over the pivot will butt together as you try to lift the bridge and prevent your raising it.  I suggest thinking about making a bracket that attaches to the end of the bridge and forms the bridge abutment.  Hinge this to the fixed layout with a pair of butt hinges with their barrels horizontal and perpendicular to the rails, one on either side of the track, and higher than the rails.  The hinge leaves would be closed when the bridge is down. 

[Roger Bielen]

On the layout I finished building for someone he already had an Atlas bridge as a liftout.  The only problem I see is the longevity for a plastic bridge.  With frequent movement better keep the glue handy.  I think you'd be better off with a metal bridge.

[dougdagrump]

And I will add one thought, set-up the lift bridge and it's approaches as a seperate power block with a kill switch attached to the bridge to kill power when lifted or not fully down. The old saying "An ounce of prevention is worth more than a pound of cure" is especially true in this application. Been there, Done that.

[dwiemer]

I think OGR's "Backshop #11" video deals with building one of these.  As Bob Nelson has explained, you need to build the blocks at the end of the bridge so that the hinge pivot point is at the height of the top of the rail.  Then, reinforce the top of the bridge where the string is to attach.  you can use heavy string like the carpet thread to do this.  Then, pick a point back far enough for the hole throught the layout top, to allow for the bridge to be lifted to full height.  I think Jim Barrett used a piece of brass tubing that was flared at the ends to allow for the string to slide without binding.  Weights attached to the other end allow for the bridge to be lifted with little effort.  As Brent mentioned, you must devise a locking method so that the bridge doesn't lift during normal operations.

Dennis

[palallin]

I use one of these for a lift-out bridge, but I actually seldom lift it out for the reasons Roger mentions.  It is a fine bridge, but the details can be fragile (made in Italy, you know), especially the cross braces under the deck girders.  They pop off when flexed, so expect them to need constant reattachment.  I don't use the walkway parts, but I'd bet they'll have the same problem.

BTW, FYI:  http://bridgehunter.com/mo/butler/mengo/

This is the prototype Atlas used.  Please note that the bridge is a Warren, NOT a Pratt, truss, and that the prototype has two, single spans with plate girder approaches.

On my layout, I have to use one double span but I am using a plate girder approach (fixed, not lift out).  Selective compression stikes again!

 

On the layout I finished building for someone he already had an Atlas bridge as a liftout.  The only problem I see is the longevity for a plastic bridge.  With frequent movement better keep the glue handy.  I think you'd be better off with a metal bridge.

[phillyreading]

I use one of these for a lift-out bridge, but I actually seldom lift it out for the reasons Roger mentions.  It is a fine bridge, but the details can be fragile (made in Italy, you know), especially the cross braces under the deck girders.  They pop off when flexed, so expect them to need constant reattachment.  I don't use the walkway parts, but I'd bet they'll have the same problem.

BTW, FYI:  http://bridgehunter.com/mo/butler/mengo/

This is the prototype Atlas used.  Please note that the bridge is a Warren, NOT a Pratt, truss, and that the prototype has two, single spans with plate girder approaches.

On my layout, I have to use one double span but I am using a plate girder approach (fixed, not lift out).  Selective compression stikes again!

 

On the layout I finished building for someone he already had an Atlas bridge as a liftout.  The only problem I see is the longevity for a plastic bridge.  With frequent movement better keep the glue handy.  I think you'd be better off with a metal bridge.

The thing is I am not in charge of buying the bridge or should say I had no part in the purchasing of it, my friend had it at his house the other day when I came over and have been working with it from there.

Also he wants to run a set similar to the California Zepher on this one track and we expanded two of the curves to 054 curved track, two more curves to work on.

Lee F.

[phillyreading]

Brent,

Thank you for sending an email. I will see when it arrives.

Lee F.

[Buckeye Riveter]

BTW, FYI:  http://bridgehunter.com/mo/butler/mengo/

This is the prototype Atlas used.  Please note that the bridge is a Warren, NOT a Pratt, truss, and that the prototype has two, single spans with plate girder approaches.

The trusses on the Butler County, Missouri prototype bridge are Warren trusses. (It says so on the link.)   Atlas calls their bridge a Pratt Truss. (It says this on their web page.)   How can the trusses in Butler County be the prototype for the Atlas model when they are not the same truss type? 

[palallin]

BTW, FYI:  http://bridgehunter.com/mo/butler/mengo/

This is the prototype Atlas used.  Please note that the bridge is a Warren, NOT a Pratt, truss, and that the prototype has two, single spans with plate girder approaches.

The trusses on the Butler County, Missouri prototype bridge are Warren trusses. (It says so on the link.)   Atlas calls their bridge a Pratt Truss. (It says this on their web page.)   How can the trusses in Butler County be the prototype for the Atlas model when they are not the same truss type? 

 

Atlas is wrong about the type.  You'd think they'd get a detail like that correct, but, though they did a bang up job engineering the miniature, they glanced at the wrong caption in the list of types, I guess. 

 

 

[dougdagrump]

Lee,

Check out this link, apologies to CTT, I bet this could be adapted to "a lift bridge" use easier than the Atlas. Plus it looks pretty cool as well.

http://ogaugerr.infopop.cc/eve/forums/a/tpc/f/3681097934/m/1351028664

 

[phillyreading]

BTW, FYI:  http://bridgehunter.com/mo/butler/mengo/

This is the prototype Atlas used.  Please note that the bridge is a Warren, NOT a Pratt, truss, and that the prototype has two, single spans with plate girder approaches.

The trusses on the Butler County, Missouri prototype bridge are Warren trusses. (It says so on the link.)   Atlas calls their bridge a Pratt Truss. (It says this on their web page.)   How can the trusses in Butler County be the prototype for the Atlas model when they are not the same truss type? 

 

Atlas is wrong about the type.  You'd think they'd get a detail like that correct, but, though they did a bang up job engineering the miniature, they glanced at the wrong caption in the list of types, I guess. 

 

 

Buckeye and palallin,

Thanks for the info but I am trying to install the Atlas bridge, not have a debate about it's realism.

Lee F.

[phillyreading]

dougdagrump,

Thank you for the information about installing a lift-up bridge. I may be able to use some ideas for the Atlas bridge that my friend is installing with my help.

A reminder to others who posted on here; I did not buy this bridge, my friend bought it without me knowing a single thing until I went over to his house.  Of course I prefer a metal bridge but I didn't buy this one nor was I consulted before the purchase.

Lee F.

[RockIsland52]

Lee,

It's nice to have someone getting you train stuff without being asked.  A couple of years back my daughter and SIL bought me a 1950s Evans Auto Car for Christmas because she was smart enough to see me looking some over on ebay while I was over at her place.  Sad to say my wife didn't take to daughter's lead.  I guess I should pick out a piece and start dropping some hints now if I expect to nurture this.  Beats the bejesus out of clothing at the holidays and my b-day.

Jack   

[dbaker48]

Now I'm going out on a limb here!  The pictures below are of a MTH bridge I have installed, (still working on the cosmetics).  But I've been playing with it for 6 months, and it gets a lot of activity, (up and down for room accessibility.)

Below, you see the bridge, the popsicle sticks are a interium height adjustment.

The bridge is all plastic, since I have a couple of heavy engines on it, I had a piece of sheet metal cut to reinforce the bottom.  (As you can see I havn't done anything with it yet, it is actually corroding a bit.) 

I don't use a pully system, but simply lift the bridge open, obviously it is hinged. 

I used blind cabinet hinges. They work really well.

\

The mating end of the bridge, I have some "knife" type track pins.  The track on the bridge comes down and slides right over the top of the blade.

 

I have also isolated the track going to and coming from the bridge.  The + is wired on the layout and - is connected to the track section on the bridge.  That way I don't have any suicide engines.  It is feasible I could back a consist off, but since the bridge overlaps onto the layout that won't happen. 

 

 

[phillyreading]

Lee,

It's nice to have someone getting you train stuff without being asked.  A couple of years back my daughter and SIL bought me a 1950s Evans Auto Car for Christmas because she was smart enough to see me looking some over on ebay while I was over at her place.  Sad to say my wife didn't take to daughter's lead.  I guess I should pick out a piece and start dropping some hints now if I expect to nurture this.  Beats the bejesus out of clothing at the holidays and my b-day.

Jack   

Jack,

I think that you misunderstood me! I am helping a friend in Lantana FL with his train layout, and he bought an Atlas bridge without telling me, guess he bought it on ebay, for his layout.

Also going to test curve radius in the next day or two.  I wish somebody would be kind enough to buy me some train stuff.

Lee F.

[phillyreading]

Yesterday went over to help my friend with his bridge again. Took some of my diesel locos and tried them around the track and bridge. Had to align the tracks at the bridge but nothing that major, pliers and a dremel tool helped with that job.

Off topic note but I find it important, MTH PS-2 locos don't work right with a Lionel CW-80 transformer as it just sits there and sounds the horn and start-up sounds over & over.

Lee F.

[Anonymous]

Yesterday went over to help my friend with his bridge again. Took some of my diesel locos and tried them around the track and bridge. Had to align the tracks at the bridge but nothing that major, pliers and a dremel tool helped with that job.

Off topic note but I find it important, MTH PS-2 locos don't work right with a Lionel CW-80 transformer as it just sits there and sounds the horn and start-up sounds over & over.

Lee F.

This is because the voltage isn't dropping to 0. Try adding a light inline with the power source, or put a passenger car or other lighted car on the track with the PS2 engine.

[phillyreading]

Brent,

Thanks for the advice but I won't be bringing that locomotive over to my friend's house any more as he can't run it around on his layout, all his curves except for two are 031.

Lee F.