Does anyone have the specs on an Atlas O Pratt Truss Bridge, specifically the single track version? I read that it's 40"L x 9 1/2"H, but I need the width.
Also, very important, the height from the track deck to the bottom of the bridge. I could have a clearance issue with the track one level below.
Thanks.
Replies sorted oldest to newest
If this is the bridge, this is the only information I could find.
O scale Pratt Truss bridge kit; single of double 2-rail or 3-rail track; ABS plastic and Styrene construction; internal steel support beams; length: 40-1/4”; width 5-1/2”; height: 9-1/2”. 3-rail version supplied with rail joiners for Atlas O, tubular or GarGraves track; price: $114.95 single track, $149.95 double track, $49.95 bridge add-on kit (converts single track to double track).
Yep-that's the one, thanks, but the one critical dimension is missing...the distance from the track deck to the bottom of the bridge. From the picture it looks like about an inch, but I'm hoping that someone with one could take a measurement.
Yep-that's the one, thanks, but the one critical dimension is missing...the distance from the track deck to the bottom of the bridge. From the picture it looks like about an inch, but I'm hoping that someone with one could take a measurement.
The track railhead to the bottom of the deck is about 1.25" as I recall. If you don't have an accurate reply by Wednesday evening, I'll post the measurements off the bridges on the club layout.
Calipers read 1 9/16" + from top of outside rail to bottom of cross frame.
Can you split the grade? By that I mean in addition the your up grade is there someway you can lower the right of way going under the bridge?
Most folks just look at the rise of an overpass. Depressing the track that will be running under the bridge may also be a way to achieve the desired clearance.
Spliting the incline/decline grade change in the same overall distance of just an incline grade can reduce the rate of grade by half. Or conversely, you can reduce the length of the grade by keeping the percent the same.
Instead of just going up 6 inches over a flat plywood, layout, consider only rising 3" and then cutting a dropped right of way 3" into the framework to split the difference.
If you are using typical 3/4" X 3 1/2" cross members you can use 7" high pieces of plywood as a gusset to add an additional cross member directly below the crossmember needing deeper cutouts.
Can you split the grade?
Calipers read 1 9/16" + from top of outside rail to bottom of cross frame.
Thanks Susan.
HEY X-RAY VISION:
I measure exactly 1.5 inches from the railhead to the bottom of the bridge structure, using a Starret 6" steel machinist's rule.
(I'm building that bridge right now.)
BAD ORDER
Access to this requires an OGR Forum Supporting Membership
