Cast Iron
There was a time when all hand dryers used cast iron covers. More specifically, they were cast iron with a porcelain enamel coating. This configuration was established as the restroom standard by the toilet, sink and tub manufacturers. The ¼” thick cast iron is incredibly durable. It is literally bullet proof. At World Dryer Corporation, they have a flattened bullet on display that proves this statement.
The porcelain enamel is almost scratch-proof. The porcelain enamel, cast iron cover is therefore perfect for any setting where vandalism is a problem. Since the restroom is a private, unmonitored location, vandalism is certainly a problem for many of our customers and this is the best solution for them.But there are some problems that come with a cast iron cover. While it is very tough once it is up on the wall, it can also be very fragile in transit. The cover can shatter if it is dropped just right. During transit, the enamel can chip off (“released enamel”) or it might wear down on the friction points so that the cast iron beneath is exposed.
The manufacturing of cast iron covers is very tricky and usually performed at a foundry that does not specialize in hand dryers. In many instances, when the iron is poured into the mold or casting, the end result is a bumpy, pock-marked surface. If this surface is too bumpy, the enamel will not adhere properly to it, leading to increased chipping. Or, when the porcelain enamel is applied to the iron, the imperfections in the surface are compounded, leaving a wavy surface. While this wavy surface may perform its function perfectly well, it may be rejected on account of its looks. There are some ways to improve these imperfections including touching the covers up by hand, but all of them add costs to the cast iron option.
There are two processes for applying the porcelain enamel to the cast iron cover – a wet process and a dry process. In the wet process, wet paint is poured over the cover. This creates a thicker, stronger coating. The downside is that it is more likely to come out wavier. In the dry process, a dry paint is applied. This creates a nice, smooth finish that is better looking, but more likely to wear through to the iron underneath. There are also various techniques for molding the cast iron. Ones that use greater pressure provide a smoother cover, but are more expensive to tool and operate.
Notes of caution:
The standard in the industry for cast iron is ¼ inch thick (25mm). There are some dryers that use thinner cast iron. These may be fine depending on the workmanship, but a thinner cast iron is more likely to experience problems. I would recommend sticking with the heavier, thicker cast iron covers for maximum durability.
Some manufactures will refer to “cast metal” or just “cast.” If it is not “cast iron”, it does not meet a cast iron specification. It is probably not as strong and durable as cast iron and certainly not as expensive.
Drawn Steel
Steel is also very strong. It is less expensive than cast iron and also lighter. If you are in a high-vandal area, I would recommend cast iron, otherwise, feel free to use steel. It’s not bullet-proof, but most restrooms don’t see a lot of gun fighting anyway.
Drawn steel covers are stamped. The heavy tool shaped like the cover stamps down on a flat piece of steel and the shape is created. The edges are then cut off and smoothed down. This is different than a cast process, where the metal is poured into a mold and cooled.
Some steel covers (like the Nova 2) have the porcelain enamel coating like cast iron, but many are simply painted. Porcelain enamel is much more scratch resistant than paint and paint is more likely to fade over time than an enamel.
Stainless Steel
Stainless steel makes for some of the nicest and most durable dryers. Stainless comes in two basic configurations: polished (or mirror) and brushed (or satin). Polished stainless is beautiful, but many people prefer brushed because brushed will not show scratches, finger prints or other imperfections as readily.
Stainless is not bullet-proof like cast iron. However, some customers say that vandals are more likely to leave stainless alone than they are cast iron, so stainless is their top vandal-resistant choice.
Stainless also cleans up very nicely and is the best choice for keeping a spotless, shin restroom.
Good, 304 grade stainless steel is very expensive. If you think you got a great deal on a stainless dryer, check to make sure that you have true 304-grade and not an inferior grade that is more likely to rust. A chrome covered dryer can look like stainless (it may even have fewer imperfections), but it is just a coating that covers another material, and it will not last as long as stainless. One way to check for stainless steel is to put a magnet on the dryer to make sure it sticks.
Die-cast aluminum
Aluminum is the lightest of the metals that we use for hand dryer covers. This creates dryers that are easier to place on any wall, saves on shipping costs, and is less expensive. Aluminum is easier to dent than steel, but it is still pretty tough and it creates a nice smooth surface that is easy to paint.Zinc
Zinc is heavier than aluminum. It is more malleable and porous and, less brittle. Aluminum has replaced zinc in many instances as it is a metal that is easier to work and has become less expensive in recent years.
BMC – Bulk Molded Compound
A BMC is a thermoset polymer. It is originally mixed in a powder form. A cake is made and then the cake is set in a mold into the shape of the dryer cover. It is not plastic and is much more resistant to high temperatures since it does not melt like plastic does. BMC is very strong and used in a number of aerospace and automotive applications where light-weight, heat-resistance and weight are important.
BMC covers stay looking great for a very long time. Since the color is integral to the material (no layer of paint to scratch off) light scratches can be buffed out. The can be mixed into any color. They are light, and they will never rust! World Dryer’s BMC cover is called WorldStone and has an anti-microbial agent mixed into it as an additional benefit. Excel™ Dryers also recently came out with a BMC cover for their Xlerator™.
While metal covers are still more popular than BMC covers, BMC has lot of nice attributes, and they are worth a consideration.
ABS Plastic
Plastic is really not tough enough to protect a hand dryer from vandalism that is common in many restrooms. Where vandalism is not a concern, a plastic cover may be appropriate as a way to save on cost, but it is still possible that the cover will be damaged at some point during its life.
Very low cost dryers almost exclusively use plastic covers. Most of these dryers are not as high in quality as others that us metal covers. But decent dryers sometimes use plastic to keep the cost down. One positive feature is that a chrome finish can be applied nicely to a plastic cover, making it look more like metal. The PHS Ultra Dry™ Drier, for example, uses this technique.
For more information on hand dryers please go to RestroomDirect.com in the US or Bavada.com in Europe.
left on the dryer. The second is energy savings. You only use the dryer for as long as you need it. Many timers are set for 30 seconds. But the user may choose to leave after only 10 seconds of drying, wasting the energy used for the rest of the cycle. On the other hand, another user may dry his hands for 35 seconds, wasting almost an entire second push of the button.
electronic sensors. When sensors first were introduced they were less reliable than the tried and push-button timers. The eyes could be either too sensitive, going off simply by the reflection of light against the surface below (a problem known as “ghosting”), or not sensitive enough, not activating the dryer at all. (You may have a particularly bright environment that is not friendly to an electronic sensor.)