Toy train operating and collecting

I'm curious as to how much you'd have to raise this bridge in order to have allowable height for an 'O' gauge train to go underneath it.

Here's the link for it: Lionel Arch Under Bridge

There is 3 1/8" from my flat table to the bottom of the arch. Got it at train show last month, havent installed it yet. It is beutiful though!!!!!!!!!!  

Spanky,
That depends on where your tracks pass underneath it. Being an arch bridge the clearance is different closer to the edge vs in the middle. I put mine on 5.75 inch risers and I can pretty much get anything under it without problem - if I were running trains under mine.

If memory serves me correct to get the 4.5 inch center rail to center rail distance for the Atlas track that puts you in the 2" clearance area of the bridge without risers. My MTH Double Stack requires 6.25 inches about the rail, so 2" + 5.25" = 7.25" so that gives me .25 inch clearance due to the .75 inches for the ceiling tile, track, and foam roadbed. If I were running trains under it I would add another .25 inch to give just a tad bit more clearance and make it look that much better.

If you can give me a better idea where the track will pass underneath, and how many, I can get you better measurements.

IMHO, they look 1,000x better painted flat black:

TXT:

There is 3 1/8" from my flat table to the bottom of the arch. Got it at train show last month, havent installed it yet. It is beutiful though!!!!!!!!!!  

Thanks, that's what I needed to know.

Brent, I'm still in the design stages of this, so I'm not sure where the track will go and at what angle it will be coming underneath.  It looks like I will be raising it a certain amount, and I may choose to actually put the whole viaduct higher to resolve some of the problems I foresee.  I'm about to update my project thread with what I've run into so check that out to see what I'm running into.  Hopefully I'll be able to post some pictures in the next evening or two.