I was wondering if there is any information regarding the protocol for replacing canvas with a rigid Bimini/dodger on a small 36-foot catamaran. I could not find a review of solid Bimini replacements. We have strong stainless steel frames. They are fixed with metal struts with no flexible straps. I do want to be able to see the sails from the helm and bulkhead mount. I want to be able to take advantage of roll up clear plastic front and side curtains. Most summers my current set stays in the rolled up position. They have since shrunk enough that they can no longer be fully snapped.
I am looking for some material that is relatively light with strength. Is there any info on the polycarbonate tops such as the Hard to Top system (www.hardtotop.com)? It seems to be light and strong, translucent. It comes in several panels to make up the necessary width. Is there any other material options that combine light weight and strength? The solid plastic systems seem to be very heavy per square foot.
Half Moon, Endeavour Cat 36
Because these are semi-custom jobs, we haven't done a dedicated review of hard-top Bimini options, but this topic is definitely worth a closer look. Hard tops are so popular among warm-water cruising catamarans that they are standard on most of the boats you see today. Retrofitting one on an older boat, however, deserves some careful thought. Your concern about weight is on target. On a catamaran like yours, the weight of the top and the structure begins to add up quickly-as does cost.
Because the Hard to Top System can be incorporated into an existing Bimini frame, it would appear to be a cost effective option, but wed be concerned about longevity of any plastic, and the translucent nature of the material seems to defeat the purpose of a Bimini, which is to create shade.
A canvas Bimini offers many advantages over a rigid one, especially to offshore sailors. Importantly, you can fold it down or remove it in a gale, when the windage of a permanent hard top can affect the boats trim and balance. And Bimini tops almost always interfere with access to the mainsail. You can usually zip out a panel of a canvas Bimini, or remove it completely as needed.
A hard dodger (as opposed to a Bimini) is less intrusive. Weve seen several custom, lightweight designs with low profiles that provide four-season protection and look terrific. For many boats, a good compromise is a hard dodger top (usually custom made), with canvas sides and clear vinyl front panels. We recently compared three types of popular clear vinyl glazing: Strataglass, OSea, and Regalite (see PS January 2014, How do Different Vinyl Types Compare?). And this month we look at the long-term results of our canvas test.
To get a better picture of the pros and cons of hard top versus a conventional canvas top, we will begin a survey of various custom shops that offer hard tops and dodgers and compare costs and materials. The more sensible hard Bimini tops that weve seen for catamarans incorporate lightweight cored panels and aircraft-grade anodized aluminum supports. Atlantic Towers in Bayville, New Jersey (www.atlantictowers.com) has a number of custom sailboat jobs to its credit. In Southwest Florida, we would recommend JTR Enterprises (www.jtrmarine.com), the family-run welding company in Gulfport that rigged the early Endeavours.
Two companies we are familiar with fabricate hard-tops and dodgers using thermoformed ABS plastic: Cruising Hardtops (www.cruisinghardtops.com) and Shipshape Canvas (www.shipshape.canvas.com). However, as you pointed out, these tops are heavier than comparable designs using cored panels.
Just about any region in the country is home to at least one custom welder/fabricator who can help you come up with design. The aim would be to keep weight minimal without breaking the bank. Wed invite any comments from owners who have retrofitted their boats with hard tops and have advice on this topic.