I need advice on bridges for my layout.
It’s 12’ x 21’
I’m using a 6" by 1/2" ribbon plywood base. with corkroadbed on 2" centers.
I’ve used typical L-girder construction for the benchwork.
Now it’s time to place the bridges.
I’m anticipating 9-12 bridges. ranging from 8" to 18" in length ( ALL DOUBLE TRACK ! )
1 18" straight
1 18" curved 20*/22* radius
7-10 8"-12" straight
The pike is Pen. Circa 1875-1920 so I can use a variety of styles.
Any sugestions for sources for double track bridges?
Where should I make the cuts in the plywood to allow just the right space for the bridges? should I place the track down first or place the bridges first?
I will probably build all the bridges first. Then cut the plywood to match each bridge. Place the retaining walls, place the bridge then lay the track.
Or should I get the track running properly 1st then then cut the plywood and drop in the bridges?
HELP!!![?]
I use the Walthers double track bridge, in a recent flyer I think they are on sale for $17.99
The real railroads hardly ever build double track bridges, esp during your time period. That being said, I bashed mine by cutting the sides off of two bridges and glueing them back together. I also scratch built one in wood. I also use woodlawn culverts, they look nice. You could also use O scale bridges and modify them. An O iron frame bridge looks good upside down with HO tracks on it, I don’t have one but seen on on another layout. Either way you suggest will work, but I use the first method of cutting and putting bridges in and laying track to meet them.
For the shorter, straight bridges you could use the Central Valley double track through girder bridge which is about ten inches long. Micro Engineering, Inc. makes a double track through girder bridge that is about seven inches (fifty scale feet) long if you want some variety.
If the 18 inch bridge has to be a single span, then you need to get a truss bridge. As mentioned above, the Walthers double track through truss bridge may suit you, although it doesn’t have adequate overhead clearance to run some of the tallest HO scale equipment. Walthers also makes a double track swing span bridge that is roughly this long and you may want to consider it for variety.
The 18 inch curved double track bridge would be best modeled as a trestle of shorter spans. Micro Engineering, Inc. also makes a single track trestle kit that could be bashed into a double track trestle. In my opinion, you shouldn’t cover that much span on that tight a radius with any kind of “through” structure. If you need a “through” structure because of clearances beneath the bridge, use a series of shorter girder spans, rather than a long span.
Good Luck - Ed
Thank you Javern, Cablebridge & Flee307
For the helpfull Information.
I’v already ordered the Walthers bridge, adutments & wings.
While I’m working on it I will continue to reasearch.
I’m looking through old coppies of MR to find a Trestle plan for the curve.
and will nodought pick up a copy of MR Bridges and Trestles#33
Thanks again for your help If you think of anything please post . ASAP
GemStoneMine,
One other thing . . .
You can improve the appearance of any bridge by adding good bridge bearings (sometimes called shoes). Micro Engineering makes white metal bridge bearings and I recommend them. I think they are about seven bucks for a pack of four. Good Luck - Ed
I need advice on bridges for my layout.
It’s 12’ x 21’
I’m using a 6" by 1/2" ribbon plywood base. with corkroadbed on 2" centers.
I’ve used typical L-girder construction for the benchwork.
Now it’s time to place the bridges.
I’m anticipating 9-12 bridges. ranging from 8" to 18" in length ( ALL DOUBLE TRACK ! )
1 18" straight
1 18" curved 20*/22* radius
7-10 8"-12" straight
The pike is Pen. Circa 1875-1920 so I can use a variety of styles.
Any sugestions for sources for double track bridges?
Where should I make the cuts in the plywood to allow just the right space for the bridges? should I place the track down first or place the bridges first?
I will probably build all the bridges first. Then cut the plywood to match each bridge. Place the retaining walls, place the bridge then lay the track.
Or should I get the track running properly 1st then then cut the plywood and drop in the bridges?
HELP!!![?]
I use the Walthers double track bridge, in a recent flyer I think they are on sale for $17.99
The real railroads hardly ever build double track bridges, esp during your time period. That being said, I bashed mine by cutting the sides off of two bridges and glueing them back together. I also scratch built one in wood. I also use woodlawn culverts, they look nice. You could also use O scale bridges and modify them. An O iron frame bridge looks good upside down with HO tracks on it, I don’t have one but seen on on another layout. Either way you suggest will work, but I use the first method of cutting and putting bridges in and laying track to meet them.
For the shorter, straight bridges you could use the Central Valley double track through girder bridge which is about ten inches long. Micro Engineering, Inc. makes a double track through girder bridge that is about seven inches (fifty scale feet) long if you want some variety.
If the 18 inch bridge has to be a single span, then you need to get a truss bridge. As mentioned above, the Walthers double track through truss bridge may suit you, although it doesn’t have adequate overhead clearance to run some of the tallest HO scale equipment. Walthers also makes a double track swing span bridge that is roughly this long and you may want to consider it for variety.
The 18 inch curved double track bridge would be best modeled as a trestle of shorter spans. Micro Engineering, Inc. also makes a single track trestle kit that could be bashed into a double track trestle. In my opinion, you shouldn’t cover that much span on that tight a radius with any kind of “through” structure. If you need a “through” structure because of clearances beneath the bridge, use a series of shorter girder spans, rather than a long span.
Good Luck - Ed
Thank you Javern, Cablebridge & Flee307
For the helpfull Information.
I’v already ordered the Walthers bridge, adutments & wings.
While I’m working on it I will continue to reasearch.
I’m looking through old coppies of MR to find a Trestle plan for the curve.
and will nodought pick up a copy of MR Bridges and Trestles#33
Thanks again for your help If you think of anything please post . ASAP
GemStoneMine,
One other thing . . .
You can improve the appearance of any bridge by adding good bridge bearings (sometimes called shoes). Micro Engineering makes white metal bridge bearings and I recommend them. I think they are about seven bucks for a pack of four. Good Luck - Ed