Archive for the ‘Uncategorized’ Category
Customer case filled with die-cast cars and trucks fastened to drywall wall.
Hanging acrylic wall display cases.
First let me say I have 6 acrylic wall cases up to 48″ wide by 50″ high, and 5 1/2″ deep, fastened to a 1/4″ paneled wall for 11 years now. The largest cases are filled with 40, 1/24 scale die-cast nascars. A case plus the cars weigh close to 150 lbs. I also had an aquarium 48″ wide 48″ high 3″ deep fastened to 1/4″ paneled wall for 4 years. Weighed approx. 280 lbs.(took it down because of cleaning hassle.)
Most acrylic wall cases may be hung on hollow walls faced with panel board, drywall, etc. as long as it’s smooth and at least 1/4″ thick.
All our wall cases have at least 4 or more 3/16″ holes and I recommend
using #8 drywall screws for paneled walls and thicker wood walls. Toggle bolts are the preferred method for plaster or drywall.
We don’t supply hardware with wall cases except for 1/8″ thick hard rubber washers to prevent metal screws against acrylic. One type fastener may not be suitable for all walls, in fact, more than 6 fasteners are recommended for different walls.
Concrete walls or other rough surfaces, or uneven surfaced walls should use a backboard similar to below.
Best way to hang against panel wall
First you need a strip of wood (hard or soft) 1/2″ high, 1/4″ thick and same length as case to be hung. Drill at least 3 holes equally spaced 3/16 dia. for #8 drywall screws.
Fasten the strip of wood to wall using a level, ( fasten one end loosely, then level the strip for rest of the screws.)
The rest is a 2 person job.
A large case should never be lifted by one corner or one end. If you do, you will fracture your case. ( break it. Case is strong fastened to the wall!)
If you can it’s best to take off the doors, then 2 people can stand up the case while still in it’s box, and gently raise the case keeping it level
to rest on the resting strip. Don’t forget to use rubber washer on each screw. Do not tighten. Just a slight snug is best. To tight will concave the mirror, not good, or worse will fracture the acrylic mirror.
If using back board use same hanging procedure.
Medium density fiberboard, or MDF, is a composite wood product similar to particleboard. It’s made out of wood waste fibers glued together with resin, heat, and pressure. MDF is appropriate for many applications, from cabinetry to moulding, because it is smooth, uniform, and won’t warp.
MDF has many advantages over plank wood, particleboard, or high density fiberboard. It’s very smooth because the wood fibers used in its manufacture are uniform and fine. This makes it have low “tear out,” which means that when sawed, the end has a smooth cut instead of a jagged edge. This also means that a coat of primer and a couple of coats of paint take well, leaving an attractive, finished surface unlike other composite wood products. MDF also has a mild reaction to moisture, meaning it won’t warp or swell in high-humidity applications like a bathroom cabinet.
Builders use MDF in many capacities, such as in furniture, shelving, laminate flooring, decorative moulding, and doors. They value MDF for its insular qualities in sound and heat. Also, it can be nailed, glued, screwed, stapled, or attached with dowels, making it as versatile as plank wood.<P>
The smooth and stable surfaces of MDF and the well compacted machined edges are prerequisites for successful finishing with a wide range of liquid coatings. Pigmented lacquers are widely used to create strong single colour effects or, using modified lacquers and a good finishing technique, unique pearl, metallic, marble or other dramatic effects. Alternatively, the natural appearance of the MDF surface can be enhanced using a transparent stain with a clear lacquer topcoat.
The surfaces to be finished should be free from dust or sanding marks. MDF, normally supplied with a 100/120 grit or better surface, will be suitable for most matt finishing treatments without further sanding. An additional light sanding with 150/180 grit is recommended when using high gloss finishes or where a minimum coating thickness is required.
As the edges of MDF are more absorbent than the surfaces, finishes applied to the edges may differ in appearance from the surface finish. In particular, the increased absorption of stain into the edges will result in a darker colour compared with the surface. With lacquers, a higher coating weight may be required on the edges to accommodate this increased absorption.
In order to control the problem, lacquer manufacturers have developed specially formulated sealers, usually two pack, at a high solids content for application to the MDF edges before finishing in the normal manner.
Stain and clear lacquer
As an alternative to obliterating the MDF with pigmented lacquer, the appearance of the finished product can be enhanced by taking advantage of the variable absorption of a stain applied directly to the surface to highlight the fibre structure.
Solvent borne stains applied directly to the MDF surface will wet the surface effectively and ensure an even colour. Water borne stains can also be used but the waxes sometimes added to fibreboards to improve their water resistance may result in uneven absorption of the stain and a consequent variation of colour.
The stained surface can be protected by one or two coats of clear lacquer with a light denib with 320 grit paper between coats. Deeper colour effects without obliterating the character of the MDF surfaces can be achieved by lightly tinting the lacquer used for the top coat.
High gloss finishes
The high stability of MDF surfaces and edges can be used to good effect for the production of gloss finishes using a high build coating based on polyester resin. At one time, a polyester finish applied by spraying would need to be mechanically burnished to achieve a high gloss surface free from imperfections. Using suitably formulated lacquers, high gloss finishes can now be obtained directly from the spray gun without a subsequent burnishing treatment. As a further development some companies are now applying a polyester base coat to develop the colour on MDF with a clear lacquer top coat to protect the surface and enhance the gloss effect. Non yellowing clear lacquers must be used on white and light colour base coats to maintain the colour.
Here’s a quote from one of the articles “Here Today, Gone Tomorrow?”, by By Dana Wegner, Curator of ship models, Department of the Navy, Naval Surface Warfare Center:
Quote: Guidelines for “Display Cases”
A few words are due on the subject of “display cases”. Make sure the model is mounted firmly on a base that is large and strong enough to protect it when it is moved or repaired. Keep the model and “display case” away from sources of direct heat, cold, vibration, humidity, and sunlight. Avoid exposing the model to rapid changes in temperature and humidity. And be sure the air in the display case can change once or twice daily, for the reason I explain next.
All things deteriorate at some rate, and some things deteriorate faster than others. Even a well-built model will deteriorate more quickly if it is kept in an adverse environment. Environmental conditions can retard or accelerate the rate of deterioration. For example, a newspaper placed in sunlight turns yellow faster than a newspaper kept in a file drawer. When things deteriorate or change chemically, they release molecules into the air in a process museum conservators call “off-gassing.” When you can smell paint or glue, whether it is wet or supposedly dry, you are smelling the off-gassing of those products. Usually the smell diminishes considerably or seems, according to your nose, to stop altogether. Nevertheless, each material still off-gasses as it undergoes inherent chemical changes, or as it changes because of heat, time, humidity, or light. One easy way to tell if your model is off-gassing is to smell it. If it is more than a few months old and still smells like glue or paint, either something has not dried yet, or something is inherently unstable. If the model or the inside of the “display case” smells like vinegar, serious decomposition is likely taking place.
Insignificant as these weak gasses seem, when a ship model is placed in a microenvironment where the air does not move much, like in a “display case”, the gasses become relatively concentrated and may begin interacting in various and unpredictable ways with the materials with which the model and case were made. Much of the interaction between off-gasses and particular materials is harmless, but some can be perilous. Think of a “display case” as a heatless cooker that will bake a model and anything else within its walls.
Model builders can help retard deterioration by allowing a little free air into the display case. Air inside even loosely fitted display cases can be one hundred times more stagnant than the air in the surrounding room. The air in the exhibit case should exchange at least once or twice a day. A 1-inch diameter hole will allow a cubic yard of air to exchange naturally daily. So, a 1-inch hole is sufficient to ventilate an exhibit case with an interior of 36 by 36 by 36 inches. Of course, many modelers display their work without exhibit cases, and if you are willing to accept some mechanical breakage, that is fine. However, frequent dusting then becomes necessary, because dust, when combined with humidity in the air, will form a concrete-like coating that is difficult to remove, even with solvents.