Christopher Brimley updated October 4, 2011

Categories

Christopher Brimley's Tags

Archives

Browse Articles » How-To Text View Magazine View

  • Vertical Access Hatch

    by Doug Geiger, MMR

    Photos by the author

    Theres a hatch in this scene; can you find it?
    Model Railroading - January 2002 - Page 42

    Access for model railroad layouts has always been a difficult problem. A good trackplan allows for all the track, especially turnouts, to be within easy grasp. Maintenance chores like cleaning structures or scenery in hard-to-reach areas will be difficult, if not impossible without some kind of access. Maintaining an easy reach of no more than three feet or so can be hard, especially if your trackplan calls for wide scenery vistas. Also, as the layout gets higher, access becomes more difficult and the reach distance diminishes. Access needs to be considered during the trackplanning stage of a layout since the scenery and trackwork should be dictated by your reach limit.

    Access has traditionally been done using four methods: ladders, grab tools, open holes and hatches. All have pros and cons. Step stools can be effective if the user is always aware of the safety liability of a ladder. Trying to reach the desired scenery can place you in a very unstable position, i.e., stretching across finished scenery. One slip on the ladder and your reaction will land you right on the layout. Grab tools will enable you to reach into a scene and pluck out a derailed piece of rolling stock, but the tool can also damage fragile equipment or can drop the piece onto the scenery.

    If the scenery is such that a hill, trees or large building can provide a view block of the access opening, then thats the best solution of the four methods mentioned since no moving scenery is required. Nor does it have any unsafe practices. Try to anticipate the tallest visitor to your layout to ensure the hole is hidden. If, however, tall trees wont block the view or the scenery is too low so that the open access hole cannot be hidden well, then a hatch is probably required.

    Hatches come in several flavors: lift-out, slide-out, drop-out and vertical. The lift-out is simple: a section of the layout is pushed up, taken out and set on the floor (or some other convenient location) to open up a hole in the layout. Usually, lift-outs require two people for operation, one under the layout and one in the aisle. Lift-out hatches need to be as small as possible to keep the weight to a minimum to avoid dropping the hatch. A common way to disguise a lift-out hatch is with a lake surface. Lift-out hatches can potentially damage the removable section of scenery because of its transport above and across existing scenery.

    The slide-out hatch usually requires some fancy benchwork to allow the section of the layout to be shoved in or out to make a hole. And it will consume a considerable amount of floor or aisle space. This hatch is not very common.

    The drop-out hatch is usually a hinged piece of the layout that swings downward (or upward) to provide access. Weight is not as critical since the hatch remains attached to the layout. The scenery on the drop-out hatch will have to clear any existing fixed scenery, so the swing arc must be allowed for. The hinge will need to be very strong, especially if the hatch scenery is traditional plaster hardshell. The drop-out, like the liftout and slide-out, can damage scenery on the hatch since it is slightly portable.

    For some layouts, the best hatch seems to be the vertical solution. It is pushed up (from below) above the surrounding scenery and is held in place with pins, seemingly to float above the layout. This hatch moves in a fixed traverse, so scenery damage is minimal. The only requirement for the vertical hatch is that there is sufficient room above the hatch so the moveable scenery section has clearance. Clearance is also required for an operator to fit under the hatch and still be able to provide assistance to whatever the problem is (rerailing equipment or cleaning scenery). Watch out for the ceiling!

    All four hatch solutions can be difficult when disguising the hatch edges. But again, creative placing of bushes and buildings can hide an edge. Regular maintenance on the hatch edges will keep the hatch hidden. Paint or stain any raw or rubbed edges that occur while moving the hatch. After all, the idea is to hide the hatch as much as possible to the viewer.

    In many situations, the vertical method hatch can be the best choice. Begin construction of a vertical hatch by identifying the limits of the opening. Try to make the hatch be as small as possible, but still allow for an operator to work within the opening. The hole does not need to be rectangular; it can be any shape. Now box in the sides of the hole with scrap plywood. These pieces f orm the limits of the hatch and provide a stable edge for the scenery at the hatch. Connect these hatch sides to the permanent benchwork so they become stable.

    Then, make two slide pockets from scraps of 1/2" plywood and some 1x2s. These pockets are illustrated in both Photos 1 and 2 . During construction, add one sheet of paper as a shim to the pocket sandwiches to allow a 1x4 vertical support to easily slide

    This view shows the access hatch fully raised. Note the arrow drawn on the vertical 1x4 to provide a reference for the operator when pushing the hatch open. The plywood sides of the opening protect fixed scenery from being damaged during hatch movement.
    Model Railroading - January 2002 - Page 43

    in the pocket. Attach each pocket to the hatch sides with yellow wood glue and let dry. Note that the two pockets do not have to be parallel to each other. However, they must be vertical in both dimensions so use a level and some shims (like cardstock) to ensure they are straight. Photo 1 also shows how these pockets can be attached to either existing benchwork or the plywood sides of the hatch.

    The vertical supports for the hatch are made from straight 1x4 stock, as free from knots as possible. Rub a candle on all four sides of the verticals to allow these to slip easily in their pockets. Cut a piece of " plywood slightly shorter than the longest dimension of the hatch. It should be no wider than 6" to minimize weight of the hatch. This piece becomes the horizontal support platform for the hatch. Attach this board to one of the verticals. Use a 1x1 cleat at the butt joint to help strengthen that joint. Attach the horizontal plywood plate to the vertical member with yellow wood glue and several screws. Let this assembly dry completely overnight. Now place this assembly into a pocket. Slip the other vertical in its pocket and attach it also to the horizontal plate and use another 1x1 cleat for strength at this joint.

    Add a drawer pull to the bottom of the support plate for a handle. After both verticals have been attached to the horizontal support plate and are in the slide pockets, push the assembly upward to position it slightly below the lowest point of the fixed scenery surrounding the hatch. Temporarily clamp the verticals to the slide pockets. Drill a 5/32" hole in each vertical, located in the center of the pocket. The hole should penetrate both the vertical and the pocket. Then release the hatch slowly and allow it to rest back on the pocket(s). Drill another 5/32" hole through each vertical, this time using the previously drilled hole in the pocket. Two 16-penny nails provide the anchors for the hatch and should fit snugly into all these holes. Open and close the hatch several times to allow the wax to transfer to the pockets. Use the nails as pins to hold up the hatch when open. Open up the hatch and insert the pins so the hatch stays up. Mark a large arrow on the vertical just at the top of the slider pocket (see Photo 1). This marks the furthest extension of the hatch.

    Now using some extruded Styrofoam (not white bead-board), fashion the hatch scenery base. The foam is layered and carved to whatever thickness and contour is required for the hatch. Glue the foam to the plywood plate when you are satisfied with the fit. If the hatch is in rugged terrain, you may need to laminate several layers of foam together to match the existing scenery surrounding the hatch. Use Styrofoam-compatible cement when gluing the layers together and to the horizontal support plate.

    Close the hatch and perform whatever scenery construction you like to the foam scenery base. If you are using conventional plaster, build up the necessary scenery contours on the fixed sides around the hatch opening and add the plaster coat right across the seams and onto the foam hatch. When the plaster is dry, use a new hacksaw blade and cut out the hatch from below. Its messy, but it works. Patch any cracks or pulled off plaster with some Sculptamold® compound or more plaster. Add the necessary ground texture and trees. Use bushes or clumps of foliage to help hide the hatch seam.

    Access hatches can be difficult to construct or use, but in many cases, the hatch is a necessary solution to allow certain scenes. Hatches come in a variety of shapes and sizes and implementations. The vertical access hatch is easy to build. So dont be afraid of that deep scene: just add a hatch.

    Article Album (1 photo)

    Share - Report
0 comments