Have you guys have any ideas for making some simple abutments for the Steam Era bridges? I would like to make some for several bridges. I’m pretty sure if I can make a template I can make them all the same dimension and simply build the terrain up below and behind them. I was first thinking I could simply mount the bridge ends onto the 3/4" plywood roadbed but have my doubts that this is the most reasonable way to go with this. Can use some ideas for dimentions and a way of making them.
Thanks
Abutments are made from concrete, stone, or wood cribbing. The latter would be used only for very small bridges. You can either use cast ones, made by yourself or others, or you can build them individually.
My choice for individual is recreating a concrete abutment with styrene. You have a lot of flexibility of design. But ya gotta figure out how to make it look like concrete. There’s gotta be an article somewhere on that.
Don’t forget that bridges sit on bridge shoes that sit on abutments. And the bridge shoes are under the end meeting points of the pieces of a truss bridge. Lots of times there’ll be a kind of shelf for the shoes, with a higher piece of concrete holding back the roadbed and ballast.
And, don’t forget, besides holding up the bridge, abutments hold back the dirt. Or rocks. Or lava. Well, maybe not lava.
You can, of course, build a styrene master and cast copies. I’ve just started doing rock casting for scenery, and it’s a lot of fun. The wort part is when you get air bubbles, but ya just gotta fill 'em. Yup, kinda fun.
Thanks Ed I did realize I have to add bridge shoes to the bridge ends and that is on my list of to do’s. I was thinking styrene may be the way to go and make a master mold and perhaps scribe the cast if it pops out ok. Need some dimensions though. Thanks
Bridge abutments can be done using various methods. in open frame, cookie-cutter and even spline, i find it best to add a pine “sub- abutment” that the subroadbed can be attached to, You need to calculate the bridge span and shoe shelf as well as the finished “facing” material you will use. The sub-abutment is a structural riser that allows attachment of you finish of choice. In your case/ era I would consider cut stone/ granite block. Later ones are done on concrete. The critical portion of the abutment is the shoe shelf and retaining ‘wall’, wing walls usually are incorporated of the same material as well.
early pics of the ME bridge install shows the framing/ supports. This is to be finished w/ 1/4" plaster castings depicting well aged concrete
A different approach combining 2 bridges, center pier was able to take both bridge shoes at same level (CV truss and plate girder) Note small wood block 2 left (old abandoned abutment derelic collasping stone veneer to be added)
I’ve used purchased plaster cast stone abutments, plastic Atlas abutments and pine wooden abutments painted to look like concrete abutments. Wood abutments are probably the easiest to make.
Thanks Bob this info helps. I guess I need to figure out how much of a hump I need at the bridge shoes abutment jointing area so that the bridge/shoes sits on the abutment top and at the same time allow the rail to be level.
Do you mean functional abutments, as in solid for engineering reasons to really anchor the bridge firmly, or do you mean cosmetic abutments that look the part, but that don’t actually do more than that?
I use roadbed for the engineering part and wood glue, and I have built faux concrete abutments out of both carved extruded insulation foam and cardboard. I also built timber abutments for my last major timber trestle in HO.
Here is the timber abutment.
This is the form, hollow, of the MDF concrete type:
Thanks.At first I was thinking I could simply place the bridge ends on the 3/4 plywood roadbed and do as you say " a cosmetics abutment" built up from below the bridge area but then I started thinking haveing a solid abutment out of concrete would be better so I could mount the bridge and have the track alligned correctly then pull the bridge to continue with the scenic detailing in the rear area of the bridge. I also like the idea of a wooden abutment but wasn’t sure there were wood abutments in the 20’s steam era.
Selector can you tell me what size timbers you used for the timber abutments? Also would timber abutments be used on truss bridges as well as trestle bridges etc? Closer view looks fantastic.
All of my abutments are cosmetic. I have used Woodland scenics castings, embossed paper wall cards, and Atlas bridge piers, all very scpuccessfully. To use a bridge pier, cut off the bottom with a razor saw, and cut the back off so that it generally conforms to the terrain. Put a little Sculptamold or plaster on your layout and slap the “abutment” in. Use the plater product to cover any gaps between the cut edge of the pier and the terrain.
Weather the abutment, finish the scenery, and you’re done.
Lynn, the timber beams scale milled lumber of cedar, but you could use anything. The strips I purchased from a hobby shop are about three feet long, and the thickness of the square profiled strips (looking at them from the end) is 1/4". I cut them to length, used wood glue sparingly to stack them to take the shape I wanted, and then painted them with “Burnt Umber” acrylic craft paint from WalMart. I taped or pinned them into place, backfilled with scale ballast, glued the ballast until saturated, and then was able to remove the pins or tape once the wood form had bonded to the ballast and the ballast had hardened.
Thanks Crandell I will be sure to use your technique on one or more of the bridges. Some how I’m thinking a concrete abutment just wouldn’t do a trestle any justice.[:)]
I managed to get a styrene mold made up last nite and the first pour done. I’m not sure if I may have made it too thick as I have about 1.5 feet for the step and 4.5 feet behind for the rest of the top of abutment. I made the pour approx 19 feet high and the mold top width about 23 feet across while the bottom of the cast came out to 25.5 , so there is a slight angle top to bottom. The bridge end sits on the step nicely although I’m thinking the 4.5 depth behind the step may be a bit much. I don’t think I would want to make a cast much higher than 27 feet as for one I think the bottom should be well built up and covered with surface area and more than 27 feet may not look correct. By the way for use that use styrene alot I highly suggest try MEK if you have never tried it. Makes life so much easier.
That’s darned good for a first effort, and it’s quite usable. I would shim under the stringers to firm up the deck surface and then you can lay any length of track right through that point, along the bride, and out the other side to place the joints off the deck. That way, the joiners on either end provide sure power to the entire bridge length. You could also hot glue, but you’d have to cover that somehow.
