Your most frequently asked questions… answered.
Editor’s notes (2019)
The FAQ and discussion below has been mildly edited to eliminate typos, make it clearer who the authors are and which boats they themselves have (by hull number and boat name if known). Wherever possible alternative (i.e. current) references to products & suppliers are provided.
The bulk of this FAQ was originally generated as a Q&A in the period 2005 – 2015. In this period Lester Helmus acted as a clearing house for questions and responses, but some respondents would also write direct to each other, hence some of the overlapping answers you see in the FAQ. In places there are 2019 and subsequent comments, drawing either on my own experiences, or from other Corbin 39 owners and sources, including our Corbin 39 Group on Facebook. More comments are most welcome and this FAQ will inevitably grow.
We have attempted to contact all contributors to the 2015 version of the FAQ. All responses have been most supportive, thank you. If you are a contributor who has yet to respond please contact us.
As will be apparent there are multiple viewpoints on some topics. Sometimes, but not always, this can be traced to differences in arrangement between the boats of the various authors. Some of the topics raised are not so much a Q&A, as simply being a statement of why a particular owner thought something was a good idea, which of course it may not have been at all. Make your own mind up.
If you have further comments or suggestions on any of these questions, or wish to pose new questions, or describe various issues you have faced and/or overcome, then please contact us either via the Facebook Group or via the Website.
[Remark as of November 2019: Quite a lot of the links to drawings & photos are not yet reinstated due to workload. However I also know quite a few of the relevant images have gone astray. You may find the relevant photos in the individual boat’s entry. Please email us if you have any of the missing photos, drawings, etc.]
a. On my Corbin the Inverter/Charger (Heart Interface 1000 watt) is under the nav table seat. You won’t see much in the photo. I have stainless grilles to assist cooling air flow. The fan comes on occasionally. This location minimizes the wiring distance from the batteries and from the breaker panel. I believe I used #2 gauge wire, actually welding cable. This is not tinned but costs a lot less and I took pains to seal all the ends into the heavy duty lugs(from an electrical supplier) with heatshrink and silicone caulk for the wire ends. I used Ancor lug crimper, p/n 701010, W. Marine 214080, and squeezed it in a vice where possible, otherwise using a heavy C-clamp (tricky as it tends to slip off) inverterundernavseat.jpg. David Salter (s/v #050, Opportunity)
How do I rewire my mast? Can you please help. I am trying to do some rewiring in the mast (Isomat): radar, coax, and a triplex wire for deck and steaming light. Are there internal conduits in the mast that extend below the side exit? Do I need to pull the mast? Gene Stoddard (#158, Swell Dish).
a. All masts are probably different. I have an Isomat clone (Cinkel Canada) and it has 3 extrusions inside the mast, 2 either side near the front and one aft.. They go the full length except that one or two (I forget which) are cut by the upper spreader supports. The extrusions each hold a plastic conduit tube and may be cut at whatever height one desires. I believe the only way to resolve wiring problems is to pull the mast. David Salter (Here’s my mast base, Pic 1) (#050, Opportunity).
b. We had an Isomat mast previously on our Corbin. It had two conduits, one fore and one aft. The wires within our conduits were bound together with cable ties every couple of feet or so. These wires flex snakelike back and forth across the conduit taking up much of the conduit space. We needed to take our mast down to get the wires out of the cable wraps and add another wire in the conduit. We disconnected all the wires, slid the entire bundle out, added a wire, attached it with cable wraps, slid the whole bundle back in, and reconnected everything. It was not as difficult as it sounded, and went quite smoothly. Hope that helps, Stephen Lefneski (#187, Toboggan).
c. I have an Isomat mast which I rewired several years ago. I had no conduits in the mast initially but Isomat sells various size conduits which can be slid up the mast from below into a retainer slot so they are fixed. In order to rewire your mast properly, and certainly to install additional conduits, the mast must be removed and put on sawhorses. Pull out all the old wiring and even remove the mast head temporarily for ease of pulling. Find the supplier of Isomat masts and accessories and purchase the new conduits you need. The conduits can be trimmed at the exact point where wires need to exit such as at the spreaders for spreader lights or radar domes before continuing on the the mast head. I would suggest signal wires be in separate conduits from the power wiring. If you have room in the conduit you might consider a spare wire for some future device or antenna you might want to install. Be sure to file smooth the holes where the wire exits the mast and that the wires are not pinched when exiting. All new wiring should be in double insulated sheaths and be tinned stranded wire of the proper gauge for the devices run. When the wires exit at the spreaders or at mast head they should exit at 90 degrees and make a slight bend down before heading back up again to the device. This will prevent water from entering the mast. Good luck with your rewiring. Jack Verheyden (#127, Kathrian).
d. There is no way you can deal with this mess without pulling the rig. The wires in the conduit will be impossible to pull out or use as pull throughs for new wiring. I rewired Two Pelicans mast down. The reason the wiring exit is higher than the conduit end is to form a drip loop. This exit would be the one to use for all the wiring including the radar if its cable is properly shielded. On deck I would mount an inverted U-shaped stainless steel conduit, one end attached by a flange to the deck where the wiring feeds below, the other end half the length of the U would be where the cables are fed in, then up and over the U and then down. With a suitably sized piece of pipe and a flange welded on the longer end you will have a barrier to sea water going below through the conduit. Plug the pipe after the wires are fed in, either with putty or with a piece of plastic tubing where the wires are fed through, one end inside the mast opening, the other slipped over the inverted shorter end of the conduit. Use the proper sized silvered copper wiring……expensive but a one time fix. Good luck, Jeremy Parrett (#101, Two Pelicans).
e. At the time most Corbins were being built, Isomat spars did not have conduits in them. Instead, they had two internal extruded tracks, similar to the sail track on the aft outside of the mast tube. Isomat would take the appropriate lengths of mast wiring, secure miniature slides every 12 – 18 inches along them, then “hoist” the wiring harness in one of the internal tracks, while fishing wires out of the mast tube at appropriate locations. With more complex wiring harnesses, they would split the bundle into two harnesses and use both internal tracks. There is no way to adjust the wiring on a setup like this unless the mast is unstepped. You may have something that’s been retrofitted, including a conduit (you should be able to see fasteners on the outside of the mast tube used to hold the conduit in place). In some cases, where advanced planning was employed, it may be possible to fish new wires through a conduit while the mast is stepped, but it is always easier while the mast is laid flat. In any event, your biggest issue may be the exit plate on your mast; a non-standard fitting for an Isomat spar and one I’ve never seen before. Good luck, Chris Reynolds, former owner of #083, Tamalmar, Corbin 39 pilothouse cutter.
f. The rewiring of a mast is much, much easier done with the mast down, especially if you are going to replace all the wiring. That being said, many times the wiring is filled with 3M 5200 at the base of the mast to prevent water from entering. To get wires out of 5200 is not an easy task if you don`t have access to it. There are internal conduits but the radar wire was big and often times did not make it inside the conduits. The radar cable usually goes out at the 1st spreader so it is about 20`long. Again, May I suggest that the mast be taken down for re-wiring. Have a wonderful day. Marius Corbin
I am installing an SSB radio in Whaleback and am seeking any assistance regarding the installation of the “counterpoise” grounding system. I am using a 3″ copper foil and would like input from any skipper who has experience with adhesives, connections to tanks, etc. or general feedback on the overall “counterpoise” install. Tim O’Neil (#138, Whaleback) Constitution Marina, Boston
a. A link for some info on SSB, www.yachtwire.com/ssb.pdf . Regards, Frank Bryant
b. For a (SSB Ground Plane) I used 3M 5100 to attach my copper. I was told by a radio man in Seattle that I should shoot for 100 sq.ft. of ground plane. I have 75 sq.ft of 18″ copper foil that is soldered to adjacent copper foil of similar size. I have kept most of this foil below the waterline which is important. I used 3″ foil to connect between my large copper foil area and two 12″x 3″ Dynaplates. I have also incorporated one of my fuel tanks. There are a lot of people that don’t think that is a good idea. Electrolysis can be a problem. I have been told that the signals ??? travel along the service of the foil. People with good radios will keep their foil clean and replace it when corrosion starts to deteriorate it. It’s also important to use 45 and 90 degree folds when changing direction with the 3 ” foil. One should also solder the folded edge. I am not an expert, I do a lot of listening , but I have one of the better radios in a fiberglass boat. I was able to routinely talk to New Zealand from the entire length of the west coast of North America. A good radio is a lot of fun and you are in a position to help others when their radios are not doing the job. There are a large number of radios that will not reach very far. Richard Bacon (s/v #043, Balmacara)
c. Richard, Thanks for your helpful response. Can you advise me regarding the source of your 18″ copper foil? I called the local metal people around Boston to no avail. I was going to try to source copper insect screen next. I was also concerned re the airex core…that it could affect or interfere with counterpoise, but it appears in your case it does not. Again thank you for your response and three cheers for Lester. Best Regards, Tim O’Neil (#138, Whaleback)
d. I got my 18″ foil from an outfit called Pacific Steel. They are located here in Missoula, MT. They ordered it from the west coast. 1 800 446 4766 . I don’t think that the airex is a problem but you can get away from the airex if you get close to the center of the boat where there is no airex. I think the key is to have it below the waterline. R. Bacon (s/v #043, Balmacara).
e. Here is a link to a supplier of copper foil ( SSB Counterpoise ) you may have it already …………. I ordered some myself too. http://www.basiccopper.com/?gclid=CMT5k_2_vJkCFSEgDQodeQhA7A Regards, Frank Bryant.
a. Regarding your earlier request for an AC schematic, I don’t have one and it would be very simple. We have 6 active AC breakers, plus a couple of spares. Each breaker feeds a chain of AC receptacles (one feeds the water heater, not yet commissioned). These are all Pass & Seymour stainless steel, hospital grade (yellow plastic) in plastic housings. I didn’t use a GFI as they are reputed to trip intermittently due to the marine environment. David Salter, (s/v #050, Opportunity)
a. The wiring behind the panel shows a fuse block at the left that has AGC fuses for the light loads of instruments (GPS, Nexus instruments, VHF etc.). The copper strap is the SSB ground connection. I have lots of AGC in-line fuses, all listed now I believe. They protect the light loads of various pieces of equipment that would not be protected by the breaker feeding them. I used white wire for ground as I had lots of it! Almost all the wiring is 12 gauge, to minimize voltage drop. I have “pony panels” in about 7 locations throughout the boat. Each is fed from one breaker and consists of a junction block, e.g. Blue Seas #2408 (W. Marine 214991) or similar. This avoids having all wires go back to the main panel. Each sub circuit has an in-line fuse See Pic. David Salter (s/v #050, Opportunity)
b. The back of the Paneltronics breaker panel (hinged open) shows the AC below with a fibreglass box covering the AC wiring, made by me. The mass of wires is organized (!) with number labels stuck on and covered with clear heat-shrink There are circular wire loops attached to a fixed piece of wood behind the hinge, so that the wire will tend to flex and not fatigue with opening and closing of the panel door. All wire ends are crimped to ring terminals and covered with heat-shrink. I recommend the Ancor ratchet crimper, p/n 702017, $46.99 at W. David Salter (s/v #050, Opportunity)