Radar Arches

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RocketRob

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Hi there, just picking up a C-Dory 25 and looking to add a Radar arch on the Roof. Are there any Arches that utilize the rails ? or better to screw the Arch directly into the Roof ? Are there known C-dory Arch builders? Any tips appreciated. Thanx.
 
Usuallly you have the rail made locally because of the expense and difficuly shipping. Usually the arch is high enough that the inflatable dinghy pontoons will fit under it while inflated. The wiring can be run thru the tubing, and into the interior of the C Dory where it can be easily be run forward, down the forward, helm side piller of the pilot house. There the power and or sensor cables can be run to the MFD or radio. Usually an aft spreader light is on the aft side of the radar arch, VHF antennas (if two) on the outside of the radar arch, radar in the center platform. any other antenas are inside of the VHF antennas.

The arch can be made in aluminum or Stainless steel and rocket launchers can be buit in. I usually stored at least one fender between the SS grab rail and the outward leg of the radar arch on the cabin top. Usually a Bimini top attatches to the aft part of the cabin top on the C Dory, rather than to the arch. I had one made in Long Beach many years ago. There should be aluminum or SS fabricators in the Ventura area. I did have a full boat cover made in Ventura many years ago, as well as bimini and camper back in Long Beach (20 years ago).

I know that the best arch builder in Pensacola is booked up 6 months. This may be true in other ares, so make your order soon--"season" begins in a couple of months. At times the Factory has them in stock, or can refer you to a local to them, rail maker.

If you are just mounting a radar, a single strut mount is available, with angel down 5 degrees. I have made radar support struts using off the shelf Home depot PVC commode parts, and painted to prevent UV damage. This simple strut support has been used on several of my and other's boats: two toilet flanges and a straight piece of Schedule 80 4" diameter PVC pipe. I would not make it more than a foot high. One of the toilet flanges is bolted to the inside of the center of the cabin house, and the other is bolted to a plastic platform to match the bolt pattern of the bottom of the radar. The wiring is run thru the 4" pipe into the cabin house. Some of the C Dory 25 do not have core in the raised center "hat" section of the roof.
 
thataway said:
Usuallly you have the rail made locally because of the expense and difficuly shipping. Usually the arch is high enough that the inflatable dinghy pontoons will fit under it while inflated. The wiring can be run thru the tubing, and into the interior of the C Dory where it can be easily be run forward, down the forward, helm side piller of the pilot house. There the power and or sensor cables can be run to the MFD or radio. Usually an aft spreader light is on the aft side of the radar arch, VHF antennas (if two) on the outside of the radar arch, radar in the center platform. any other antenas are inside of the VHF antennas.

The arch can be made in aluminum or Stainless steel and rocket launchers can be buit in. I usually stored at least one fender between the SS grab rail and the outward leg of the radar arch on the cabin top. Usually a Bimini top attatches to the aft part of the cabin top on the C Dory, rather than to the arch. I had one made in Long Beach many years ago. There should be aluminum or SS fabricators in the Ventura area. I did have a full boat cover made in Ventura many years ago, as well as bimini and camper back in Long Beach (20 years ago).

I know that the best arch builder in Pensacola is booked up 6 months. This may be true in other ares, so make your order soon--"season" begins in a couple of months. At times the Factory has them in stock, or can refer you to a local to them, rail maker.

If you are just mounting a radar, a single strut mount is available, with angel down 5 degrees. I have made radar support struts using off the shelf Home depot PVC commode parts, and painted to prevent UV damage. This simple strut support has been used on several of my and other's boats: two toilet flanges and a straight piece of Schedule 80 4" diameter PVC pipe. I would not make it more than a foot high. One of the toilet flanges is bolted to the inside of the center of the cabin house, and the other is bolted to a plastic platform to match the bolt pattern of the bottom of the radar. The wiring is run thru the 4" pipe into the cabin house. Some of the C Dory 25 do not have core in the raised center "hat" section of the roof.
Click to expand...
Mr T, Thanks very much. You just flooded my little brain with a lot of great info. I will definitely want to add a bimini . Do the bimini receivers bolt directly to the roof of the aft cabin? then pick the position for the arch, if that even matters? The arch feet may be far from the Bimini. Would love to see a photo of your PVC Radar solution. Im still undecided about the arch to have the Rocket Launchers. I think there might be good rod storage in place as the boat is setup for fishing, in Which case the radar mount would suffice. Does the arch have any real practical advantage holding a dingy? Or simple enough to tie down the dingy either way.
 
I believe Mr T was on the "A" team. No worry. My C Dory moniker is "Thataway", or some members started calling me "Dr. Bob". Yes, I am an MD, and spent half of my time in academics teaching and half the time in private practice of Internal Medicine and Nephrology. I started learning about boat building during WWII, when my dad refastened his 26' sailboat. I repaired wooden and fiberglass boats in 1952 at a YMCA camp on Catalina Island, and same year started to skipper my dad's boat in ocean races when he was away on weekends. My wife and I built a 38 foot sailboat for World wide cruising from scratch (Fiberglass hull in a mold, not wooden), and rebuilt/restored several boats including a Cal 46 sailboat in which we spent 4 seasons in SE Alaska. We have been 3 x thru the Panama Canal, sailed 2x across the Alantic and to Hawaii.

Unfortunately my photos have been corrupted in the transfer to the new format of the forum. About half the photos in my album are not mine. Many are missing, including the ones of one of my "commode commode radar mount". I probably could go back to one of my archived hard drives to find the original unless the administrators can help me find the missing photos and restore my album.

The arch can help keep an inflatable in place, but not the primary way for us. I tie an inflatable dinghy to the cabin railings, SS or Teak, depending on the year of the boat. I never trailer the boat with the inflatable on top, inflated, except at low speeds. Highway speeds will blow the bottom out of an inflatable. Friends had this happen to them.

Most of the radar arches bolt directly to the deck. A good sealant is used to be sure no water intrusion occrs. On the Starboard side of the aft leg a 1" hole is drilled to allow the cables to pass through. I forgot to mention that many move the anchor / all around light to the arch also-- (Folds down when there).

The forward panel of a Bimini often is attatched to the aft edge of the cabin top with an "awning rail". (this is a round track, with a slot on the aft edge for the canvas, which has a "bolt rope" in its front end. I have also had Bimini's which attatched with snaps or "lift the dot" fasteners. I prefer the bolt rope, because it is water tight. There should be a panel of the Bimini to zip open (both sides have zippers) to facilitate boarding. The bottom of the bimini legs are on a fixed point on the gunwale , or on a track (often on the inside of the gunwale, so it can lay flat when fishing. On some boats the aft leg of the Bimini top is fixed up in place instead of straps. The bow pockets have zippers on them. A good source for fittings and visualization of them, is "Sailrite.com". Making canvas items is not difficult and very rewarding, because you get just what you want, and save a whole lot of money. You don't need an expensive sewing machine either--many older sewing machines will handle light canvas work (up to 3 layers of Sunbrella, with the correct needes and threads.
 
On the subject of canvas works, I need to replace a few snaps on my cockpit enclosure. Any snaps better than others?
 
I purchased some a few years ago on Amazon. Not very good quality. Here is a good article from the Sailrite website:

www.sailrite.com

How to Select High-Quality Marine Snap Fasteners

Learn how to choose the best marine snap fasteners for your projects, considering factors like durability and ease of use. Understand the difference between four-piece and three-piece snap sets and why high-quality fasteners matter for securing marine covers, upholstery and more. Discover...
www.sailrite.com www.sailrite.com
 
I order my snaps and other fastners from SailRite. You can count on their quality. You might get good ones, if a brand name, or not, on Amazon. Local craft stores may also sell them. For setting, I use either a hammer and setter, or a device which fits over a set of square jaw Vise Grip pliers, and make a nice set. I don't have. one of the fancy setters, with the $500 "Handy Press" pull down lever that SailRite sells. The $10,
 
There is some related info here:
olekils

Post in thread 'Radar/Radar Arch/VHF Considerations'

I updated my roof situation with a few things in mind: I wanted to eliminate holes in my roof, be able to carry/access surfboards from either side, replace the existing grab handles, and keep enough room clear to be able to jump off the roof. I ended up coming up with this design where the radar, spotlight, anchor light, GPS receiver and VHF (AIS + VHF sharing same antenna) all mount in the center of the rack, and all cables are internally routed through the SS tubing and into the cabin through the aft starboard foot. Wiring was a PIA and it took a bit to get the feet and overall...
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