2 weeks ago I was laying my track and came to the reservoir where I needed a bridge. Aha, I had thought of this already and had a Central Valley Pratt Truss Bridge kit readily on hand to be built. Ok, I thought, I should be able to knock this out in a few days. NOT!! opened the box and there were at least six sprues filled with parts, beams, gussetts, stuff I didn’t recognize, etc. Don’t panic, after all, I once built a model of the battleship Bismarck, I can handle this I said and began to work away.
2 weeks and ten mistakes later, I finally finished. This will serve as the center span for the Croton Reservoir Bridge on my layout. The other two spans are large cement arches at either end. I will use concrete tunnel portals for the faces of these arches (I hope). I have Micro Engineering bridge track which I will install when all three spans are completed.
I modified the standard bridge kit by adding 8 roof braces (obtained from extra beams left over in the kit). Also, I added extra lacework at both entrances and 4 more tension cables. For tension cables, I used guard rails from old Athearn tank cars (don’t throw that old stuff away). I used red spray paint that was left over from one of my kid’s school projects. I then dullcoted it with Testor’s dullcote and weathered it with Bar Mills weathering powder.
This is my first attempt at any sort of bridge and I am curious to see what others think of it. Let me know what you really think as I am a long time modeler and I can take the criticism or the praise. So, for your consideration, here is my version of the Central Valley Truss bridge kit, already painted and mostly weathered:
That’s a nice model, and it looks like your assembly did it justice. I think the photos look very orange, much more that than rust. Still, it’s one of those things that flash does to your pictures. I’ve done a bridge in Moss Green spray paint, which came out pretty well as the primary color. Then I used Instant Rust on it to age and weather it. The bridge spans what may be a salt-water inlet, so I wanted to put a lot of weathering on it.
This is an Atlas bridge, no where near the detail level you’ve achieved, but it’s an example of how Instant Rust looks:
That bridge will be a real focal point. Can’t wait to see the Doodlebug crossing it.
Yeah, MrB, the pics don’t really give justice to the color - it looks more orange in the photos than in person. I also still have a light layer of grimy black weathering which will be added when the all three spans are finished (so I can do them together).
I LOVE that rust effect on your bridge - outstanding! Looks like the bottom could fall out at any minute! I can’t believe that is an atlas bridge.
Here are two pics I’m using to help me. The first shows the base color I was trying to achieve before weathering. The second photo is an actual prototype photo I took of the bridge just a few months ago. When the second layer of grimy black is finished, I hope my bridge is somewhere in between.
Thanks for the comments so far! I appreciate the support as I nearly did not make it thru the construction and I am probably more pleased with myself than I should be. [8D]
Nope, be pleased, that looks great. I love the idea of useing the odl hand rails for tie cables. Adds a lot of realism. Nice choice on color too. Really snazz up the layout and hows off the detailsl better than flat black.
Very well done! With the masonry arch approach spans it should capture the flavor of the prototype quite nicely.
My initial impression was, “Gorgeous red lead primer color,” which could lead up to one of those, “Find the painter on the layout,” scenes. A couple of (model) square feet of the Putt’s standard bridge color, with the painter, scaffolding, paint pots…
Last time I crossed the prototype bridge, there was a NYC 4-6-2 on the point.
Chuck (native New Yorker, modeling Central Japan in September, 1964)
2 weeks ago I was laying my track and came to the reservoir where I needed a bridge. Aha, I had thought of this already and had a Central Valley Pratt Truss Bridge kit readily on hand to be built. Ok, I thought, I should be able to knock this out in a few days. NOT!! opened the box and there were at least six sprues filled with parts, beams, gussetts, stuff I didn’t recognize, etc. Don’t panic, after all, I once built a model of the battleship Bismarck, I can handle this I said and began to work away.
2 weeks and ten mistakes later, I finally finished. This will serve as the center span for the Croton Reservoir Bridge on my layout. The other two spans are large cement arches at either end. I will use concrete tunnel portals for the faces of these arches (I hope). I have Micro Engineering bridge track which I will install when all three spans are completed.
I modified the standard bridge kit by adding 8 roof braces (obtained from extra beams left over in the kit). Also, I added extra lacework at both entrances and 4 more tension cables. For tension cables, I used guard rails from old Athearn tank cars (don’t throw that old stuff away). I used red spray paint that was left over from one of my kid’s school projects. I then dullcoted it with Testor’s dullcote and weathered it with Bar Mills weathering powder.
This is my first attempt at any sort of bridge and I am curious to see what others think of it. Let me know what you really think as I am a long time modeler and I can take the criticism or the praise. So, for your consideration, here is my version of the Central Valley Truss bridge kit, already painted and mostly weathered:
Wow! What a great response for my bridge. I’m glad everyone likes the little details - that is one secret about modelling I learned a long time ago - the little details go a LONG way!
Chuck! You rode on the Put? I wasn’t even born yet when they stopped passenger service in 1958. You mentioned the Put’s standard bridge color - would you happen to know what color that was? I have been unable to find that out in my research. The ‘painter’ scene is an interesting idea.
Jeff - the color looks very much like the Golden Gate Bridge - that was exactly what I thought as I was painting it. The pictures really don’t give the color justice - perhaps I’ll try some outdoor photos for better color clarity before I install the bridge. Anyway, I have to agree with many who say that the color will catch attention - and that was the idea. This bridge will be a focal point on the layout and that was exactly my intention.
Now I will get to work on the masonry arches and post more pics later today or tomorrow, I hope.
i agree.it really look’s great in my book.i only have the atlas ho bridge’s.guess i’ll have to look into bridge’s from this mfg and other’s.keep up the good work.terry…
I agree that this is a fantastic bridge. That being said, you did ask for ALL thoughts. [:-^]
The engineering may need a small tweak. The extra tension members on either end of the bridge (in the triangle sections) look wrong. It’s been decades since engineering school, but I believe that the end truss angled beams need compression braces rather than tension. ie replace the rods with beams. I may be wrong so you should check the prototype to be sure.
Good job nit-picking, can’t wait to find out if you were right. I looked for someting wrong or badly done and couldn’t find it even when blown up GOOD JOB!!!
My dad was a civil engineer, so he might notice the difference. But for most of us, me included, I would never notice whether a member was a compression or tension brace. That is way more technical than most of us get. So I’d say, enjoy it, if somebody comes to visit and says something about it, tell them, “Yeah, I did that on purpose to see if anyone could notice it!” Then give them a cup of coffee as a reward. [;)]
First off, I think it is a nice bridge. I have two of these kits and haven’t built them yet, but selected them because I could tell the detail was very good.
I design and supervise bridge construction and fabrication for a living.
First off, the earlier post stating the tension members in the first triangle do not belong is a correct statement. Members are sometimes located here but are always compression members. Their primary purpose is to help strengthen the bridge in the event of an accident or derail. The end diagonals are crucial to the bridges strength and if they were substantially bent in an accident, the compression force there would possibly collapse the bridge. The inner diagonals also serve to brace the main end diagonal but must themselves be able to resist compression to do so. I recommend a pair of channels from Evergreen Styrene products in each of the four locations.
Second, I like the primer color, but would also add a painter to the scene and have a substantial portion of the bridge finished in a more traditional color. That is strictly a matter of taste and nobody can say what you did was wrong, especially with your other prototype photo. My bridges are painted aluminum color, which goes well with the rust weathering I do later. I would paint bridges either aluminum, grey, or almost black, unless there is a specific prototype you are trying to match.
Third, the extra parts you appear to have added to the portal bracing up top also don’t belong. Very few train enthusiasts will recognize that, but for purests they will think something is wrong. Depending on the height of your equipment, you may find you need to take them out.
My final point is regarding operations. If a bridge as this were used on a modern layout, a severe speed restriction would be in order, effectively stretching your mainline. Even for a turn of the century layout, a modest speed reduction
Thanks for this info, sort of a mini-primer on bridges of this type. I kind of understand what you are saying to a point, then I am lost. Is it possible for you to post some pictures to go with your technical explanation so that we can learn from it? Make it sort of a mini-clinic. Things like what is the difference between a tension and a compression member? Do they look different, or is it the positioning that makes them different? And what would/have you done differently on the bracing up top that you mentioned? I think that would help some of us non-techies a lot.
I am learning a little bit on this bridge, it will help very much.
Many thanks to those who know bridges. I am not knowledgable about bridges at all other than the required bridge law and how to interpret fire department ratings (Very small signs) that sometimes allows me to cheat on that severe weight restriction.
I looked at that bridge here in this thread and thought it’s too orange. Maybe its the camera but it’s me. I probably will use Floquil weathered black on my bridges.
One thing I dont yet understand… If I approach this type of a span on the main with a very large steam engine with a good sized manifest, what would the prototype do with this bridge in terms of speed, loading and signaling requirements?
Dino and Karl, you’re right about the tension braces at the ends. I checked the prototype (see picture below) and they are indeed BEAMS and not RODS. I’m glad you mentioned this before the bridge goes up because I might just fix that if I get the gumption.
As far as the portals go, I’m not sure I understand what you mean. I have already checked for any height restrictions although there is never a guarantee. I was shocked at how low the portals are on the prototype bridge (see second pic below). In fact, this bridge has a whole second layer of bracework at portal height all the way across the bridge. I have never seen this before and not being an engineer, I have know idea why it was built that way. This is ironic since this bridge was used on the New York Central’s “High & Wide” freight line into the 1960’s.
The color really looks much better than the pics. For some reason, I have always had trouble with shades of red on my digital camera. It looks alot more like the second picture below which is the effect I was looking for:
Here are some terms I learned about bridges for those who are interested:
Compression - effect of forces PUSHING on each other (i.e. vertical compression beams or braces). Materials used in compression must be hard like steel beams.
Tension - effect of forces PULLING on each other (i.e. like pulling two ends of a string). Materials used in tension are often flexible, like steel cable (tension cables).
Gusset - steel plate riveted or welded on sides of a beam where two beams meet.
The other two spans are finished!! The bridge is now complete and this is how it will look minus a small modifcation or two to correct engineering accuracy. It is 31.25" long or approximately 225 scale feet long. Here are new pics of the entire bridge with all three spans complete (the first is the prototype):
Click Pics to Enlarge
The next time you see this bridge it will be installed on the layout. It’s been fun sharing the experience and overall I am very pleased with the results of my very first bridge! [8D]
I made my masonary arch bridge with 3 2X4s with the arch cut out nailed side by side. I then clad the sides and under side of the arch with some .010" thick Styrene sheeting. I applied some construction paper with a random stone pattern from Micro-Mark. It has an adhesive back which sticks to the styrene sheet well. I, too, had a masonary arch at each end of two double track through truss bridges from Walthers. I made the support pier for the middle section where the two truss bridges joined out of a 2X4 stood on end and cut to the correct length. I then covered it with the same random stone patterned construction paper. Tweet.
