Rich's Lift Bridge Project

Very nice, look forward to you progress

Hello , very nice project and very well thought out. 

Now I can See Them and BOY are they AWESOME!  

Chief Bob (Retired)

Outstanding work, Rich!  Thanks for sharing.

Nice design.

No avoiding the rail angle cut with the hinges where they are. Looks like you could make some relief in the frame behind the lower part of the hinge for some track power cut-off micro-switches.

Don't forget to kill the power back from the bridge enough accommodate the longest passenger train with lighted cars. They will pass the power if it's too short.

Great Job!

Very cool!

Peter

Another thought- here is a lift bridge design that incorporated a gas/spring support rod, like an automobile trunk or hood support. Makes the lift easier and holds it in place for you.

Edit: here is an application of a micro switch to control approaching track power

Very innovated. Love the fact that you can scenic under the bridge. Your goal was to disguise it to blend into the layoyout and you did a fantastic job. 

Very nice work and great idea. Thanks for sharing.  Nick T

Moonman posted:

 

Don't forget to kill the power back from the bridge enough accommodate the longest passenger train with lighted cars. They will pass the power if it's too short.

Thanks for the tip.

I don't run many passenger trains, but that's something I certainly never thought about. I am designing the power-off  sections on either side of the bridge, but only enough for 3 locomotives.  I'm really not that worried about dropping anything off the layout with the bridge up. The "3 loco" power breaks should do the trick for me.

Nice looking bridge.  We made one for our modular club, we have 1/2" Plexiglas as the base, the bridge is bolted onto that base.  It uses a piano hinge on one side and 1/2" pins and mating sockets to align the bridge when it's down.  A pair of micro-switches interrupts power to the adjacent modules when the bridge is up to avoid "drive-bys".

gunrunnerjohn posted:

Nice looking bridge.  We made one for our modular club, we have 1/2" Plexiglas as the base, the bridge is bolted onto that base.  It uses a piano hinge on one side and 1/2" pins and mating sockets to align the bridge when it's down.  A pair of micro-switches interrupts power to the adjacent modules when the bridge is up to avoid "drive-bys".

Nice work Rich & John!  John, I think you mean "drive-offs", right?

Liking the Signal in the Picture of the Bridge too.

Great work,John

CGWforever posted:

Gunrunnerjohn, Do you have pictures with closer details?

Not handy, those were just a couple of snaps we took some time back.  Actually, I misspoke as well, we ended up using two big hinges, the piano hinge didn't work as well, I forgot about that change.

Nice bit of engineering and excellent carpentry. 

Rich, that is very impressive. The wood work looks like it came from an expert carpenter! 

I also like the scenery base under the bridge. Great idea!!

bigtruckpete posted:

The wood work looks like it came from an expert carpenter...

Thanks pete!

Hmmmm... maybe I should become a politician?  I mean, if I can fool you that easily...

Don't sell yourself short Rich, that is a very nice looking bit of carpentry.

Great job, Rich.

Nice. How does it work with the track in place?  My lift bridge "hinge axis" is usually at the top of track rail or above.

Here you have the hinge axis well below the track. Won't the lifting track interfere with the base track??

Hi Alan

Everything you mention is what I was trying to solve. The tests I did with track temporarily in place worked great.  I wish I had shot some photos or video of that test!

The key is to have the hinges and the gap in different places with the hinges being above, or in my case, below the tracks. Let me whip up some diagrams tonight and I'll post them so you can see what I mean.

Fabulous work !!!!!!!!!!

thanks

alex

Great design and some really high end carpentry skills  - fantastic project.   I am really looking forward to your progress.  

Ed

Nice work. Keep up the great work. Thanks for posting ang please show us your progress. 

Nice. Looks like it will be quite heavy? 

Heavier than I had intended for sure, but not that bad actually.

If I had to do it over again, I know exactly how to cut the weight almost in half. Actually, I considered this a prototype at one point so I could build a lighter one, but my wife said: "Why? This one isn't heavy at all". Being that this is the first time my wife has ever showed interest or given input towards my work, I decided to use it as built.

She's an engineer with an aerospace degree. How am I gonna argue with that?!

Excellent work!  Not sure of your track plan, but you need a straight section of track on approach to the bridge that is almost as long as your longest car.  Or the car swing will hit the bridge when entering or exiting.

Dan

loco-dan posted:

...you need a straight section of track on approach to the bridge that is almost as long as your longest car.  Or the car swing will hit the bridge when entering or exiting.

I've checked for that.  The curves are wide enough ( 088 ) that even my Lionel 89' auto racks won't hit anything.

Here's a close up of the bridge area from my track plan:

I used the gas spring method.  I found the article on line someplace, will have to look for it.  it has all the dimensions and plans needed.

I can lift it one hand and when fully open just misses all the crap above it.

Actually, it was the Atlas bridges that are the heavy item. Your design looks very efficient.

I did the low tech approach and did a two stage lift out. The Atlas bridge lifts out for the "Highline" , and 2nd lift piece is the base. Sorry for the blurry photo..

Alan asked about the track gap and the possibility of the track getting pinched or damaged. Here's how it dealt with this.

1. This side view shows the 45º angle of the road bed at the gap (track not shown, but would be directly on top with same bevel as road bed) The gap is roughly "1/16 -ish" wide.

2. Here, we see the bridge open with the hinges below and behind the beveled gap which allows the bridge to open without pinching anything.

3. The bridge only opens to a 90º vertical. The track above will not crush the track below.

Bob:
I'm still working on a gas-piston idea to keep it from falling down too quickly.  Yours looks like it works well.

Alan:
Looks great. The bridges do add some weight, but it's really not that heavy. If my kids can open it easily, (that was my benchmark) then I'm good.

Here's how I'm doing the "seamless" scenery.

1. I'm placing 2 pieces of styrene painted like concrete on the sides of the abutment. The gaps will be tight and not easily noticed.

2. The scenery will cover the area something like this.

2. 

      Hi Rich, great looking bridge! Here is a web address that shows installing a gas cylinder to help keep it up and make it a little easier to lift. I tried to may a hyperlink, but Im not that good yet.

        http://www.slsprr.net/features/bridges1drwgs.htm

LOL I guess it makes it's own.

Rich, you're design is excellent! And your carpentry skills are are equally as such. I like the idea of a scene under the lift up bridge. I am toying with that idea myself. Unfortunately my carpentry skills are lacking. Your illustrations are helpful. Thank you.

Thanks for the link, Mike!