Issue 135: Nov/Dec 2020
Clamping Up…
Edson Marine clearly has an eye for what the market needs, adding to its products a garden hose connector fitting made by Banjo, one of the best-known manufacturers of this style of fitting. It’s an industrial-grade, cam-lock fitting made from glass-reinforced polypropylene (like Marlon through-hull fittings) that uses a pair of stainless steel lever cams on the sides to clamp a lip on the male end to a thick, EPDM gasket recessed in the female part.
These are the same design as fittings I have used in chemical plants for 40 years; they are the industry standard for good reasons. They are rugged, fast, and drip-free. There are no O-rings or washers to lose or replace, and they aren’t proprietary—the cam and groove profiles are standard and fully interchangeable with the same type of fittings made by other manufacturers.
If there is a downside, it is bulk. The fittings are prone to snag when dragging hoses (but snagging won’t hurt the fitting). If additional security against accidental opening is needed, run a cable tie through the lever rings; this is a common industrial practice.
These fittings are rated to 100 PSI, well above average municipal water pressure. With regard to UV degradation, they should perform as well as other UV-resistant fittings. I know we left fittings like these out in the sun in refineries for years and it didn’t seem to cause any damage.
For more information: edsonmarine.com —Drew Frye, Good Old Boat Technical Editor
…And Clamping Down
In my experience, quick-release fire extinguisher mounting clasps are cheaply made and easily broken. Bungee cord can solve part of this problem, but it eliminates any quick-release capabilities. A better approach is the Davis Instruments Quick Fist all-rubber, one-piece clamp. These clamps will not corrode and are easy to mount with #10 bolts or screws.
After mounting the extinguisher, I cinched the clamp tight and cut off the excess on each strap. The single clamp holds the extinguisher like a vise. To release, I give a quick tug on the securing band and the extinguisher is free.
The clamps come in two sizes to fit a range of tank diameters. The smaller model is advertised to secure cylindrical or oblong objects 7/8 inch to 2¼ inches in diameter, such as boat hooks or dinghy oars. In practice, I found these clamps able to tightly grip only objects in a narrower size range, from 1 to 2 inches in diameter. The larger model will hold objects measuring about 2½ inches to 7½ inches in diameter. The company claims the larger clamps can even be used to support dive tanks.
Davis Instruments advertises these clamps as being made of transportation-grade rubber. I asked Niels Kisling of the sales and marketing department what this means. He said it’s a rubber that holds up better outdoors, one that doesn’t seem to dry up and crack in as short a time period as other rubber products. He said transportation-grade rubber “may have something to do with UV inhibitors or specially formulated rubber.” I suppose only time will tell.
For more information: davisinstruments.com —Roger Hughes, Good Old Boat contributor
Thank you to Sailrite Enterprises, Inc., for providing free access to back issues of Good Old Boat through intellectual property rights. Sailrite.com
