I have a around the room,20'x20',shelf layout.I have to span a 80" gap across two doors,which will only be used when operating.I am trying to build something that will be light,stable and removable and about 8" wide.I thought about 1/2' plywood atttached to a aluminum L girder frame to keep it from sagging. Any thoughts,or ideas on any other way to do this?
check out what rich c did here & posted on trainboard:
http://www.trainboard.com/grapevine/album.php?albumid=558
there's another album dedicated to the drop in.
turns out you don't need massive benchwork to make the bench work.
M.C. Fujiwara
My YouTube Channel (How-to's, Layout progress videos)
Silicon Valley Free-moN
Have you considered using steel stud material. I've used it to carry single tracks across moderately long spans, and have one stretch where two studs with a piece of plywood between support three parallel tracks.
HO trains don't put much stress on the steel, which I mostly use rain gutter style. I have no idea what would happen if heavily-weighted O-scale locomotives had to be carried, but I wouldn't hesitate to try.
I also use steel studs (nominal 2x4 size) standing on edge as 'C work like L' girders. Two girders 42 inches apart span 74 inches, with 24 inch cantilever sections on both ends. On top, a layer cake of trackwork on five different levels, visible and hidden. So far, I'm pleased with the results.
Chuck (Modeling Central Japan in September, 1964)
I think Chuck's idea is the best one. The steel stud will not warp, ever, regardless of the weather in your train room. It's probably cheaper than aluminum L-channel, too, though I haven't priced either of them.
I would put girder bridge sections all the way across, both for scenery and to prevent the trains from skydiving.
It takes an iron man to play with a toy iron horse.
On the line with Chuck's idea, you can gain additional strength by adding blocking and place a 1/4" plywood bottom. This "box" should be fairly light and strong.
As a carpenter and thinking "wood" I would feel more comfortable with a plywood box. 1/2" birch plywood top and sides and a 1/4" bottom, glued and screwed with internal blocking @ about 24". This box w/ sides of about 4-5" should almost hold your weight if leaned on.
If at all possible, use a brace or bracket mounted between those 2 doors. This would essentially cut that span in half allowing your lift out section to be built of smaller dimension and weight.
I believe it is wolfgang that had showed a liftout with some fantastic electrical connection that doubled as locating pins as well. maybe he or someone can link to it. The elevator article in MR a few months back also used similar system. I believe it incorporated kill to adjacent track power when removed also.
Modeling B&O- Chessie Bob K. www.ssmrc.org
bogp40 On the line with Chuck's idea, you can gain additional strength by adding blocking and place a 1/4" plywood bottom. This "box" should be fairly light and strong. As a carpenter and thinking "wood" I would feel more comfortable with a plywood box. 1/2" birch plywood top and sides and a 1/4" bottom, glued and screwed with internal blocking @ about 24". This box w/ sides of about 4-5" should almost hold your weight if leaned on. If at all possible, use a brace or bracket mounted between those 2 doors. This would essentially cut that span in half allowing your lift out section to be built of smaller dimension and weight.
Going even further with the box beam concept, I have built an 8ft box beam using 1x3 pine for the sides, 1/4" plywood for the top and bottom, and 2" foam inside, all glued together. You could substitute 1/4" plywood for the sides provided all joints and especially the foam were properly glued. This would be considerably lighter - although the two 1x3s were a reasonable weight to begin with. The 1x3 did give me the extra material to put a 1/4" by 1/4" notch at top and bottom so that I could get a better joint.
Your big adventure is going to be handling an 8" x 80" beam in a closed-in room. You will want the storage location for the beam close by and easily accessible. When I finish all parts of the layout, I will have a 60" liftout section that goes across the window, which is also the emegency exit for the basement bedroom. I've made sure that the plan includes a place nearby to put the liftout when not in use. Because of the emergency exit, my liftout will normally be removed, not normally in place.
my thoughts, your choices
Fred W
Put a helix on each side and go over the doors. Just a thought. It can realy ruin an operating sesion when some one opens the door and bangs thier head on the bridge while a train is going over it. Dont ask me how I know.
Pete
I pray every day I break even, Cause I can really use the money!
I started with nothing and still have most of it left!
My liftout span is 61 inches long, 6 inches wide, crosses the bathroom door and a closet door. I made it from 1 * 4 pine with 3/8" plywood "bottom". Two inch blue foamboard sits atop the plywood. I took the trouble to make a 3/8" rabbit in the pine to accept the plywood, and glued everything together. It's strong and rigid, and the same technique would do a 80 inch by 8 inch liftout span.
I laid flextrack across the liftout and then cut the rail with a dremel to make sure the track lined up properly. The liftout section has 1/4 inch dowel pins that mate into holes in the supporting ends. Electricity is carried by some clever two pin connectors I found at the auto parts store. (Radio Shack is no longer with us up here).
David Starr www.newsnorthwoods.blogspot.com
My idea may be just a little elaborate but it will solve your problem:
utilizing 1/2" or greater plywood cut yourself some 1' X 1'-- gussets. That 1' X 1' is the minimum size--depending on how your benchwork is constructed one side of these gussets must be long enough to protrude at least six inches out into the doorway(s). Bolt the apex of these gussets to the benchwork on either side of the doors leaving them just loose enough that they will fall out of the way when not in use. When you get ready to install your "bridge" across the doorway(s) swing these gussets up and secure them in place with some sort of pin arrangement. Use the protruding ends as support for your bridge.
For a "bridge" you could use a hollow core door which, I believe, come as narrow as 15".
From the far, far reaches of the wild, wild west I am: rtpoteet
We have plans for the lift out on the new pike using splined masonite. I tried a piece of flat steel but it was way too heavy even for the 40" section. So my buddy and I (he being a retired cabinet maker) decided on laminating 1.2" strips of masonite to each other glued togher with yellow carpenters glue. I borrowed an idea I saw on Rick Rideout's L&N where he did somethign similar when constructing a large bridge. He glued Central valley plate Girder sections on each side to make his bridge look like a bridge. We plan on using a double track Walthers Truss bridge in the center with a Central Valley double track plate girder on either side. Is it prototypical I don't know but it will look better then bare masoniste
Do you really need to be able to use the door to the kitchen? I would look at that first. If you realized or decide you don't you could add on to your layout, have that new portion fully sceniced, and then add some sort of bridge. It will be easier to span 40" instead of 80, and a bridge would look good like that. I personally like the big bridges with the stell arch ways rising over head and roadway connected to that with beams/cables, but there is also a bridge with that type of construction in town. I don't I've driven over that bridge since I had my last new car and was almost blown into the semi in the next lane. I was all the over to the right and the gust blew and when the gust died a little bit I was driving on the center line. I think that was the only time I've gotten honestly scared when driving.
A car caddy style of carrier maybe just the ticket. While this carrier is not made to be a bridge, I don’t see why it couldn’t fill bill. The car caddy in the drawing (my rendering) is one style used as a way to move cars on to and off of a layout.
Johnnny_reb Once a word is spoken it can not be unspoken!
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