I am set to remove the factory dorade box on the starboard cabintop in order to use it as a pattern to build two new boxes (port and stbd). Heading down tonight to pull the lexan top off, but can anyone who has removed these before tell me how the box is attached to the deck? I don’t see bolts in the ceiling of the head/shower, so I assume the dorade is held in place with adhesive only or screws into the deck (you wouldn’t think that would be very strong…but it’s still there 25 years later).
I’ll be installing air scoop vents atop both new units, but the port side will be lined with heat shielding in the event that I eventually re-install an LPG water heater.
You may have your work cut out for you. The lexan top is easy…simple wood screws.
My dorade boxes are held down by simple “L” shaped light angle irons inside the boxes and by what appears to be 5200. The angle irons are hardware store items, held down by simple wood screws. I tried several mechanical means to release the 5200 bond (heated flexible metal putty knife, wire, etc), and the “Anti-Bond” which is supposed to be good at releasing 5200. (www.antibond2015.com)
The challenge with Anti-Bond is getting it in contact with all of the 5200. Hinterhoeller used good solid wood which does not bend and give you any increasing opening between the box and the gel coat as you try to pry it up. Gel coat damage is a serious concern while prying (I can fix wood quite well; gel coat not so well). Several hours work got me about an inch at the drain hole on one dorade.
Last year I had a very good yard rebed my grab rails and hatches (above my skill level) and asked them to try to do the dorade boxes. They looked at them and recommended resealing the angle iron screws and leaving them alone. The 5200 is obviously doing its job.
If you were rebuilding the dorade box anyway, you could remove it by destroying it. If you cut/chopped the box down to about a half inch above the gel coat, you might be able to remove and preserve the pattern of where the box meets the gel coat.The box is otherwise basic box construction with a rabbet around the top into which the lexan is set. Building two new boxes, or taking good, detailed measurements of your existing box may be your only answers.
Good luck.
Joe Tierney, Allegro, 1992 NS33 #64, Annapolis, MD
I removed the dorade boxes last winter to refinish them. They are mounted with something akin to 5200. The four small aluminum L-shaped brackets inside the boxes do not seem to have been used to mount the boxes but probably were used to hold them in place while the adhesive set up. I made a jig to remount the boxes and did not re-use the brackets. When the boat was surveyed water was detected in the core near the boxes and I now believe it was from the wood screws used to mount the boxes. I investigated when the boxes were removed and and the core in a few of the screw holes was wet. I enlarged the holes, cleaned out the wet core and filed the holes with epoxy. The trick to remounting the boxes is to keep them in place while the 5200 sets up. They will tend to slide down the coach roof. My boxes do not have the clear plastic top. They are solid wood. It appears that originally the frame was mounted in place and the top was screwed on after the frame was mounted. This makes removing the screw holding the bracket difficult when trying to remove the boxes without disassembling them. In any event, the only way I could break the 5200 connection was to use a hack saw blade, hand held, in a gloved hand. I simply cut the boxes free from the coach roof. The process worked out well. The two screws in the aluminum brackets that I couldn’t unscrew were able to be cut off with the hack saw blade.
I haven’t tried it yet but I have been advised by a capable boatshop tech that the best way to remove them is with a very thin piano wire. After removing the top and the screws from the 4 “L” brackets, wrap either end of the wire around a 6" piece of wood dowel and “floss” the boxes off (by placing the wire on a corner of the box and flossing back and forth working between the cabin top and the bottom of the box until you cut through to the other side). I would recommend you DO NOT use 5200 to re-install, 4200 is more than capable and is much less problematic when it needs to be removed again in 2038 (I’ll use a silicone based sealant when I do mine and rely on the strength of the 4 “L” brackets to keep them in place).
Last month’s BOAT US magazine had a very good article on marine sealant’s and adhesives which would be a good addition to any boaters library. There is also a good article on re-bedding deck fittings which should also be helpful (links below). Good luck with it.
I tried the wire first, and while it worked, it was clumpsy and once I switched to a hand held hack saw blade I wished I had used it from the first.
Michael Passero
NS 33, #42
New London, CT
Just to put my two cents in, when re-installing the box, why is it necessary to seal it to the cabin top?? It should have relief holes or notches to let the water out anyway. I don’t believe I sealed mine.
Joe Valinoti
S/V IL Gatto NS30U #221 (1984)
Sea Harbour Yacht Club
Oriental, NC
My dorado box has never been sealed to the deck. At least not while I have owned the boat. It’s an easy removal to take to my shop to varnish and just let’s water flow right through. No problems at all.
Fred Rachwitz
Concerto
NS 30 U 445
Harbor Springs, MI
Northern Lake Michigan
For those out there who have the issue of removing an adhesive-attached mount such as the Dorade box, a multi-tool (oscillating head) with long-reach, fine-tooth blade is the ideal tool, as it will remove the adhesive without damaging the box or the deck. The trick, as I found out a year ago during haul out, is to draw the tool along at right angles to each edge of the box in the direction of the set of the saw teeth. The 5200 or what-have-you simply peels out of the joint!
Excellent strait talk articles on sealants. I added all three websites to my favorites list for future reference.
Allan and Judy N26C Swale Ottawa Canada.
Interesting how many are attempting the same job this year! The dorade on Yellowtail was in need of attention also. I removed the screws through those little mickey mouse L-brackets and found the box to be glued down also. I used a putty knife to work the joint open. It took about a 30 minutes.
The box was in rough shape so I made a new one. Rather than screwed butt joints to make the box, I used rabet-dado joints which makes assembly easier and provides more glue surface area as well as making a more water tight joint. I used poly-urethane glue (gorilla glue) rather than epoxy.
The little L-brackets were very corroded, I assumed from contact with moisture. The weep hole in the original dorade box was very small and not aligned with the angle of the deck. The hole on the new box fixed this problem. To replace the L-brackets, I decided to dril pocket screw holes on the inside of the dorade box. No hardware to corrode, no holes into the cabin top inside the box.
Whether to use some sort of compound or not is a user preference and I think would also depend on the sailing that you do. Certainly I’m not going to use 5200 on the new dorade, 4200 or some such is what I’ll use. SInce the pocket screws will penetrate the cabin top underneath the sides of the box, using some sort of compound will then seal the screw holes eliminating the moisture into the cabin top issue regardless of whether you’ve over-drilled and epoxy filled the holes.
Someone on another post mentioned using silicone, and some else reccommended against it. I also avoid silicone as much as possible. Silicone can cause serious $$$ finishing problems should you ever need to paint or even do gelcoat repairs. Once you’ve intorduced silicone, it can be very difficult to get rid of it!
The pocket screws work well in this situation because they’re hidden inside the box, make a strong effective fastening, and don’t place holes in the cabin top where you’re expecting water to be. Some people may know pocket screw holes as something done with the “Kreg Jig”. They are often overused and inappropriately used, but in this case they fit the bill well.
Chris Ouellette
NS 26C, #178
“Yellowtail”
Mahone Bay, Nova Scotia
Chris, thank you for the great detailed account. May I ask whether you feel that area of the cabin top is reinforced with ply? I can't imagine how screws set into balsa core can possibly be strong enough.
On my boat there is no plywood under the dorade box. With the original little metal brackets, they were only screwed into cored fiberglass as well. This is probably why they used 5200 to bed it down. The fasteners will help hold, but the main strength comes from the compound.
If you wanted to make the screws the structural fastening and forgo the compound, then you'd need to bore your holes oversize and fill with epoxy mixed with silica and then bore your pilot hole.
Chris Ouellette
NS 26C #178
"Yellowtail"
Mahone Bay, Nova Scotia