10m radar arch pics
Posted: Sun Sep 03, 2017 8:27 am
I could swear I posted this before but maybe not. Someone else asked me for a pic on my repair and ideas on recoring the Int'l radar arches:
You can clearly see the area of repair and I think this is fairly common on most. A couple of people have had rot on the top and that's a function of what was installed over the years and how well it was sealed. Mine was bone dry except for the section on each side that attaches to the hull. Aside from brown streaks after it rains, a telltale sign of rot is the triangle shaped "wings" sticking out. That's because the factory used screws to attach that part of the arch. The screws go through the windshield frame and are only visible when you remove the windshield frame trim. Once the plywood rots, the screws can no longer hold and it pops out. There is a lot of tension in this area so I used tiny carriage bolts instead of scews. This was a challenge because of the number of wires inside the windshield frame. Speaking of wiring, this is a perfect time to move the windshield mounted Nav light (could they have picked a worse location?) up to the arch. I ran an extra pair of wires in the process because I would like to move the horns off of the bow at some point.
The metal ties in the pic were temporary until the six/10 epoxy cured. The repair was just marine plywood, sealed with thinned epoxy on all edges and sides and the joined with six/10 using a caulk gun. Every single hole (and there are lots) was oversized epoxy filled and then drilled out. Anything that attaches to the arch was done this way.
The most important thing to do if you take this on is add weep holes so the water has a way to get out. Caulking the hull to arch seams just make the problem worse. If you zoom in on my pic you can see the areas I routed which are essentially just drains to the bottom of the arch. Ideally no water should get in but that's virtually impossible. Epoxy seal every inch so the entire arch is waterproof. I finished the inside with a coat of white epoxy paint. Back to caulking.... I only caulked the edges for appearance reasons, no caulk on the bottom. For this part of the boat, you really don't want the caulk to play any role in sealing.
Removal of the arch was pretty straight forward. It is only the bolts visible on the outside that attach it to the hull. The weight is supported by the dark piece of wood which sits on top of the ledge next to the windshield frame. Mark this piece very carefully before you gut everything! The location is critical so that the arch sits in same orientation and that the holes line up when you reinstall it. I made this mistake and it cost me a lot of time. The arch is heavy and you really need the bolts to just pop back in during the assembly stage. It's not something you can easily dry fit. In my case, I had to rent a van for the transport and coordinate help so be really careful at this stage. That horizontal ledge piece has to wind up in the exact same location.
If you want to go for the deluxe addition, RWS has some posts on reinforcing the arch with aluminum tubing. I think all of my comments would still apply especially on the weep holes. Since my problem was only limited to what you see in the pics, I did not add any add'l reinforcement.
Bob
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You can clearly see the area of repair and I think this is fairly common on most. A couple of people have had rot on the top and that's a function of what was installed over the years and how well it was sealed. Mine was bone dry except for the section on each side that attaches to the hull. Aside from brown streaks after it rains, a telltale sign of rot is the triangle shaped "wings" sticking out. That's because the factory used screws to attach that part of the arch. The screws go through the windshield frame and are only visible when you remove the windshield frame trim. Once the plywood rots, the screws can no longer hold and it pops out. There is a lot of tension in this area so I used tiny carriage bolts instead of scews. This was a challenge because of the number of wires inside the windshield frame. Speaking of wiring, this is a perfect time to move the windshield mounted Nav light (could they have picked a worse location?) up to the arch. I ran an extra pair of wires in the process because I would like to move the horns off of the bow at some point.
The metal ties in the pic were temporary until the six/10 epoxy cured. The repair was just marine plywood, sealed with thinned epoxy on all edges and sides and the joined with six/10 using a caulk gun. Every single hole (and there are lots) was oversized epoxy filled and then drilled out. Anything that attaches to the arch was done this way.
The most important thing to do if you take this on is add weep holes so the water has a way to get out. Caulking the hull to arch seams just make the problem worse. If you zoom in on my pic you can see the areas I routed which are essentially just drains to the bottom of the arch. Ideally no water should get in but that's virtually impossible. Epoxy seal every inch so the entire arch is waterproof. I finished the inside with a coat of white epoxy paint. Back to caulking.... I only caulked the edges for appearance reasons, no caulk on the bottom. For this part of the boat, you really don't want the caulk to play any role in sealing.
Removal of the arch was pretty straight forward. It is only the bolts visible on the outside that attach it to the hull. The weight is supported by the dark piece of wood which sits on top of the ledge next to the windshield frame. Mark this piece very carefully before you gut everything! The location is critical so that the arch sits in same orientation and that the holes line up when you reinstall it. I made this mistake and it cost me a lot of time. The arch is heavy and you really need the bolts to just pop back in during the assembly stage. It's not something you can easily dry fit. In my case, I had to rent a van for the transport and coordinate help so be really careful at this stage. That horizontal ledge piece has to wind up in the exact same location.
If you want to go for the deluxe addition, RWS has some posts on reinforcing the arch with aluminum tubing. I think all of my comments would still apply especially on the weep holes. Since my problem was only limited to what you see in the pics, I did not add any add'l reinforcement.
Bob