Scratched bridge shoe

[Bsklarski]

Cool.  Now I only have to make four of these!!!

Thanks Brian for the pics.  I assume the slider is the block under the shallower bridge (I can see a gap between the two) and the pivot is below under the deeper bridge?

Yes, all correct. BUT looking for a better shot of the shoes, I looked at the shots of both ends of that larger bridge and BOTH end are the same.. no sliding shoes. I am a little confused, but I am sure there is a reason.

[peteski]

Yes, all correct. BUT looking for a better shot of the shoes, I looked at the shots of both ends of that larger bridge and BOTH end are the same.. no sliding shoes. I am a little confused, but I am sure there is a reason.

I'm pretty sure one side has to have sliding bearings. Maybe one side has a sliding plate while the other side is bolted down? I never heard of a bridge structure which doesn't contract or expand with temperature.

[jimmo]

Or a dab of solder ground to a hex on a 0.015" brass wire, and yes, it pivots  :



jimmo, I would have to respectfully disagree with you on the shoe placement.  Cantilevering all of the load out to the very corner beyond the structure would likely allow the center to deflect and try to rip the girder off.  Placing it here spreads the load to all the members, not just the girder.  All of the load bearing including the ribs on the inside of the girder come down to that structural intersection below. 

I have observed these shoes set back from the end of the bridge.  An image showing otherwise would help!

I have an image for you but I've never posted a pic here before. How do I do that?

[GaryHinshaw]

I have an image for you but I've never posted a pic here before. How do I do that?

First you have to host the picture on the web, since we don't serve pics, then you link to it:

https://www.therailwire.net/forum/index.php?topic=23890.0

[up1950s]

Sometimes it is a roller .

http://www.google.com/imgres?imgurl=http://ceephotos.karcor.com/wordpress/wp-content/uploads/20110923-kjans-Bridge-Roller-Support-Manistee-MI.jpg&imgrefurl=http://ceephotos.karcor.com/2011/09/23/roller-support/&usg=__-iqXyWE-CiQRneb97-59-h7HdFw=&h=768&w=1024&sz=727&hl=en&start=1&zoom=1&tbnid=2isapHxBsWgMpM:&tbnh=113&tbnw=150&ei=hBAKUbPDJ7G40QHxpYC4Dg&prev=/search%3Fq%3Dbridge%2Bsupport%2Broller%26num%3D10%26hl%3Den%26tbo%3Dd%26sout%3D1%26biw%3D1920%26bih%3D854%26site%3Dimghp%26tbm%3Disch&itbs=1

[Bsklarski]

I was thinking something like that too, a roller. But it looks like a shoe design. I wonder if somehow the shoes can slide back and forth on each other by means of a roller.

[up1950s]

The HO Vollmer truss has 2 pivit shoes on one end and 2 expansion rollers on the far end .

Here is a combo roller shoe .
http://www.google.com/imgres?imgurl=http://bridgehunter.com/photos/13/89/138985-M.jpg&imgrefurl=http://bridgehunter.com/ca/sacramento/walker/&usg=__cBZ_XLaBkzROoto6otb2jrpISc8=&h=427&w=338&sz=27&hl=en&start=16&zoom=1&tbnid=yu5hV7plo0mzlM:&tbnh=126&tbnw=100&ei=pRcKUbS0B_G-0QGQuYGwCA&prev=/search%3Fq%3Dbridge%2Brollers%26start%3D10%26num%3D10%26hl%3Den%26sa%3DN%26tbo%3Dd%26sout%3D1%26biw%3D1920%26bih%3D854%26site%3Dimghp%26tbm%3Disch&itbs=1

[peteski]

One of the photos I posted earlier shows a really simple design where one mating surface is curved and it is rubbing against a flat metal plate.

[SkipGear]

John's got the shoe placement right according to my shots I took for a bridge project. That last section of girder really doesn't do anything. He is right to place it at the junction of the first stiffener rib.

Rather dark shot but you can see the shoe mounted exactly how his is done..

[Lemosteam]

Thanks for the input everybody! 

Tony, what does the shoe on the other end of that bridge look like?  I thought I remembered seeing another shot of this from you in the past.  (That clearance to the road kills me- I'd be afraid to walk under it!) 

peteski, depending on Tony's shot, I'll probably do something similar.  I would suspect that the other side is simply not bolted to the abutment and has a second U shaped plate under it that is bolted so the bridge can't move sideways.

[Chris333]

Long ago I bought a used Kato bridge that was weathered with a 2" brush    So I cut everything away except the bridge shoes and made a mold of them. They look like that same style as yours. I can't stand a bridge without shoes.

[SkipGear]

Thanks for the input everybody! 

Tony, what does the shoe on the other end of that bridge look like?  I thought I remembered seeing another shot of this from you in the past.  (That clearance to the road kills me- I'd be afraid to walk under it!) 

The other end of the bridge is in the middle of the river and I don't have a good shot of the shoes. From what I can see, they don't look any different than the shoes above though.

[unittrain]

You can also find info on google books like this one http://books.google.com/books?id=oc8NAAAAYAAJ&printsec=frontcover&dq=railroad+bridge+shoes&hl=en&sa=X&ei=S4EKUbfhBNG90QH3s4HADQ&ved=0CEQQ6AEwBA#v=onepage&q=railroad%20bridge%20shoes&f=false  I get real detailed with my bridges so I use these and also take field measurements bridges are my favorite structures so I do alot of my detail modeling with them. My only problem is I have to build them now I have them drawn up in CAD but have been hesitant to finish building a few of them do to needing parts etched and also needing to make molds and cast parts

[Lemosteam]

unittrain, that doc is AWESOME!!  Thank you very much for the link.

jimmo, based on what I see in this doc, I think we can compromise to say that the center of the pin is between the end of the girder and the first vertical rib/horizontal crossbeam  I think my shoe needs to be wider at the base...

[pnolan48]

...  I would suspect that the other side is simply not bolted to the abutment and has a second U shaped plate under it that is bolted so the bridge can't move sideways.

That would be very common.