I’m not getting any younger. So, I’m planning to build a liftup. I would like it to hinge on one end. The questions are, are there any plans out there and How do I wire it.
There is a good discussion of the requirements for lift-up sections on page 57 of ‘John Armstrong on Creative Layout Design.’ (Incidentally, he gives some very compelling reasons to use a drop-down leaf, rather than a lift-up.) Track on the leaf can be powered in the ordinary manner; just use flexible wire connections between the leaf and the fixed benchwork. Microswitches, operated by the latch that holds the lift in operating position, can be wired to kill approach tracks so unattended trains won’t pull a Wile E. Coyote.
Jimmp55,
My aching back is killing me too, and it’s only getting harder to negotiate that duck-under. If it’s possible, go with a redesign and a walk-in layout that isn’t any deeper than you can reach.
Here’s the problem with lifts AND swing-gate sections. Depending on what part of the planet you live at, local weather conditions and climate control in your layout room are a hinderance to this concept. Temperature and humidity makes it almost impossible for seamless gaps in your rails at the connections, outside of the time of year of installation.
I made an enquiry back sometime on a site frequented by people from the UK all the way to Las Vegas and Australia and they all universally said NYET, forget about it. It’s a nightmare you end up tearing out when you finally give up.
I made a lift up bridge two months ago for my N scale layout. I, too, have been concerned about alignment, humidty, shrinkage, and all that. As a result, I have not proceeded on the layout until I was sure that this, and other aspects of the layout are operating OK. So far, so good.
First, the wiring: I ran a wire from the rail to the hinge and from the hinge to the rail on the lift side. I did this for both rails. The hinge carries the current. Since the bridge is part of the staging area, I did not get too fussy about appearance except to paint the wires and hinges the same grey color as the staging area (dark grey).
Second, the plans: I went on instinct, drew some sketches free hand, tried hard to envision how things would work and how they should work, and proceeded very carefully. I made the bridge deck like a girder bridge. One-half inch plywood with a one inch piece of the plywood glue at either end and a piece of homasote set in and glued between. I glued and screwed a one-half inch piece of plywood along each side of the bridge deck. The side is flush with the bottom of the deck and rises about an inch and one-half above the deck. I also extended the sides about an inch or so beyond the length of the deck; these help to keep the bridge aligned to each side of the layout by neatly dropping onto the layout roadbed that was cut to the width of the birdge deck.
I dry fit the deck assembly in place using clamps and scrap wood at either end of the layout where the bridge would lay. I then began building and mounting the piers to the layout as the deck lay in place. It’s like suspending the bridge in air and building the supports up to the bottom of the deck. I did this on both ends, eventhough, the hinges would hold up one end of the bridge.
I attached to the hinges. I purchesd a pair of small, but sturdy, brass hinges. Place a car on the probable track alignment to make sure that the hinges are set far enough apart to aloow the moveme
If expansion is a concern could you build it from steel? My layout is a round the walls design and I have to get into the centre. I’m going to build a gate with two levels of track on it, I figured on a steel frame and steel jam to hinge it off.
Still in the planning stages.
Ken
Yeah… But it’s likely still going to be attached to wood benchwork which can, itself, expand, contract, shift, etc.
I don’t know a single person with a reliable lift-up/drop-down. I know several with one that ended up getting screwed/nailed/glued in place and is now simply an over-engineered duckunder.
In my viewpoint, they’re a poor solution. You are probably better off finding ways to live with a duckunder - chair on casters seems to be a common workaround - or redesigning to a walk-in mode.
I have not yet read the above messages, but here are a couple thoughts if you may have extreme temperature variations:
Make it so you could swap out various lengths of flextrack or sectional track during different seasons.
For example, the bridge could contain 8inch long sections of sectional track at one end of the bridge in the summer. Then in the winter, you may need to switch to a 8.125 length of sectional track.
You could design it so that the wood doesn’t care if you have expansion/contraction, because you’ll have a built-in gap. The track could easily bridge, say, a 1/4" gap without any support under it.
I also think you could make the ends adjustable - either with screws (ideal), or shims (not as ideal, but possibly eadier to implement).
Just a couple rough philosophical thoughts…
Alright - here’s another idea.
Say it’s a pretty simple piece - like 10" wide and 3ft long.
You make it so you could duplicate the piece, but in different lengths.
You could have the 3ft long piece, the 3ft long minus 1/8" long piece, etc.
This would work out better for lift-out, but maybe you could make an easy connection to a hinge.
From the information I’m putting together from so many posts above, ADJUSTABILITY seems to be the key. With emphasis on simple adjustability.
This is doable. We can go to the moon. We could definately make a lift-up gate that works in different temperatures.
This ties in to another post about painting benchwork. The expansion/contraction of wood due to changes in moisture content is a fact. The amount of expansion/contraction of wood due to moisture content changes is much larger than any thermal expansion/contraction of wood and/or rails. We typically use wood and wood products for our layout foundations and structures. To date, the primary reason given for liftouts and gates not working is wood expansion/contraction.
The expansion/contraction due to moisture changes can be controlled by
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controlling the humidity of the space the layout is located in - makes it more comfortable for humans too
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painting or sealing the wood (on all sides) during construction.
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using non-wood products (such as foam and metal) by themselves or in combination with the wood to stabilize the bridge against expansion/contraction from humidity changes.
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use a combination of techniques
The liftup bridge seems to me to be the easiest to engineer with common materials. The disadvantages are a retaining device holding the bridge in the raised position, and the hinge mounts must raised above the level of the track so that nothing is pinched during the raising operation. It is very easy to create fixed droop stops (can even be adjustable) on the frame at both ends so that vertical alignment can be maintained over the years.
The liftdown has the disadvantages of being more likely to be knocked, brushed against, or otherwise damaged in the down position, and the droop stops (pins, wood blocks, etc) have to be removable when lowering. The advantage is the hinges are now mounted at the bottom of the hinge frame out of sight, and there is no need for a “sky hook” to hold it in the up position.
The swinging gate has the disadvantages of requiring additional floor space for the swing and the need for extra bracing to prevent sagging of the non-hinged end over time. But a swinging gate
The one thing no one has directly mentioned (it is part of the John Armstrong design I cited earlier) is a solid connection between the benchwork on both sides of the gap. A good, solid sill and well-braced legs will do wonders in keeping the “ground” stable so the moving leaf won’t have too many problems. After all, if we can keep the door to the layout room free-swinging, how much harder is it to keep a lift aligned?
Another factor is that HO and larger scales are more tolerant of longitudinal rail gaps than most modelers think. The safest way to deal with that, though, is the short removable track sections mentioned by CARRfan. Two 3/16 inch gaps are workable, one 3/8 inch gap isn’t
I use two lift OUTS made of 1/2" ply stiffened with 1x2. They simply drop onto pins made from 16d nails. I leave enough rail end unspiked so that I can slide rail joiners back out of the way to take out the lift outs. One cannot be oicky herre. you must leave about 1/8" gaps so you don.t snag and tear out the in place rail. And of course one needs solid end that dont move. My round the room layout is screwed to the wall.
Using 1-inch foam on top of the plywood will take care of the expansion/contraction problem. An article in MR described cutting rerailer sections in two and using them to bridge the joint.
My $.02 is the drop down answer that we will use. ALL ours are lakes, rivers and fields so no track gets killed. the scenery extends a little to hide the joints.
The drop down track section is the design of our PHD in the impossible. 6 tracks on a swing down using bridge track on the ends. The north end rails EXTEND over the leaf that drops away and the south end is a .125 gap. The South is a piano hinge the north is three barrel locks. Micro switch kills the whole district when the middle bolt is pulled.
Material is birch plywood 3/4" thick with aluminum angle iron as a frame. Work great in the test mode will install it after the car show season.
Take Care
I made a bridge that is lift UP. I don’t agree with drop DOWN because it is too easy to walk into the features on the bridge. By having a lift UP, I have it at about a 95 degree angle for a slight pitch-back so that it doesn’t slam down by accident if hit by accident. I use contact switches to open/close the circuit powering the tracks. The section is made of 3/4" plywood, painted to eliminate any possible moisture problems. There is 2" foam glued to the top of the plywood.
I guess it’s who you know, in this case. I know of at least a dozen different examples of lift/drop/swing sections that work fine.
There are a couple of different approaches, as has been mentioned. One is to solidly anchor the outside abutments. Another is to use a metal extrusion for the bridge between (it won’t shrink and swell with changing humidity). Others build a couple of different length bridges for the seasons or use sections of rail, snap-track, rail-joiners, etc. to bridge the gap.
The key, I think, is to either engineer to allow for seasonal changes in dimension or to build so solidly that the changes are negligible.
In my case, I am fortunate that Kato offers a variable length section of their pre-fab track in N scale. Although the rest of my layout is flex, the moveable bridge is Unitrack and the sliding section compensates for any changes in dimension that result from humidity variation in the garage.
Engineered thoughtfully and built carefully, these movable benchwork pieces can work fine.
regards,
Byron
I recently built a liftup for the model railroad club I associate with, and it disconnects four tracks. The table top is constructed of 5/8 plylwood, and 1x4’s. The Benchwork is constructed of lightweight 2x2 steel uprights, and a 1x1 constructed grid topped with 16 guage sheet steel as the bottom platform. The uprights are gusseted, which keeps the uprights solid, from moving in any direction. The table top meets the uprights via a steel plate, mounted to the table top, with channels that adjust a 5/16 bolt with nuts and washers for the height adjustment. The piviot point is at track level, which moves the rails straight up, before entering the pivot angle, which allows the disconnecting rails to have a gap as small as just 1/32 of an inch. On the severing end, I mounted 90 degree joist ties horizontaly on either side, to catch the liftup section as it lands. The lift up section has 1/4" screws, springloaded, driven into an insert under the table top frame, which adjusts the track height. In the center of the liftup section, I placed two closet door rollers (plastic), facing each other with a zero gap, that comes down onto a 90 degree joist hanger mounted verticaly, which self adjusts the left and right rail allignment. The joist hangers are about a 1/16" thick. When the liftup is open, eye bolts and steel wire teather it from falling over onto itself.
I don’t know how to insert pictures into the forum. It might make what I’m talking about easier to understand!
I know it may not be prototypical or for everyone but I heard in another forum that a cutom layout builder uses re-railers at both ends of a lift up, drop down, swing or lift out section. I’m actually thinking of doing this on my layout. To get around the bumping into it problem, it will actually be behind the door with a stop to keep the door from messing it up.
I appreciate your taking the time to write your thoughts on this. I have come face-to-face with an inevitable compromise borne out of dire necessity. I must add, to the 12’ side of my layout an 18" wide hinged drop-down leaf. I don’t wi***o do this, but I must if I am to salvage what I have and to enjoy a 2-10-4 on curves that make it look decent.
I have been wondering how to fix the hinge so that I don’t have to carve a curved or beveled edge into the existing 5/8" ply and 1" foam cover. I had thought of adding blocks under the mating edges and placing the hinges between those blocks. That will have the effect that you described above.
it is amazing how this hobby forces you to use your imagination and ingenuity.
Thanks, again, for sharing your thoughts, loucad.
-Crandell
I don’t use it now because I redigned and no longer needed it.but when I used it,. the lift worked very good. I wired it too where the track was dead for about two feet on each side when the lift was in the up position., each side of the lift comtrol the power on the other for out about two feet.
I would really love to read what John Armstrong suggests, but since I live in Jakarta I cannot drop down to the local shop to pick up the book. Could you give us a synopsis of his compelling reasons to drop down rather than lift up please?
I need to chose one or the other and opinion on the topic seems pretty much evenly divided.
Cheers,