Mast wiring

[Risto and Liz]

Does anyone have a picture of the interior mast profile for an'81 367 main mast? I am pulling our mast next week to rewire and possibly rework the halyards. I would like to know if anyone has removed the masthead sheave box, what it looks like and if the mast has an internal wire slide track.
I want to explore taking the existing external halyards internal and being able to create spare genoa and main halyard as well as a topping lift for the boom.
Thanks, Risto

[SV Alfresco]

I've had mine off and re-did the wiring. Have to do the VHF coax again after a lightning strike. If it's never been off before, you've got some work. The masthead came off easy after letting PB Blaster soak on the screws overnight. I think there are about 4 screws holding on the masthead casting. I used a manual impact hammer to remove the screws. They came right off with that tool. I didn't want to use just a screwdriver because I didn't want to strip the heads. When I put the masthead back on, I used some flouorocarbon based anti-seize paste. The masthead has a ring on the inside that is used for strain relieve for the wiring. What I found in my mast (1981 367 #9) was they (the factory?) had jammed foam sponges every few feet up the mast. I had a hard time getting them out. I used lengths of PVC pipe that I screwed together with couplings and a metal hook on the end that I fashioned. The mast has a couple of bolts that cross the interior by the stays. Also ends of bolts at the winches. When I put in the wiring, I bundled them together in pipe insulation and tied them every 6 feet or so with wire wraps. Not sure this was the best way to go, it was tough getting it back in. I would like to hear other opinions because I have to do it again.

I don't know how you would run the halyards inside the mast. The sheaves are set up for the halyards to go outside the mast. If you went inside, you would also have to keep the halyards separate from the wiring.

I saw a guy at the Newport,RI boat show with a Cape Dory 45 that had riveted in a pvc pipe to run the wires in. He drilled some holes up the mast that he used to insert a tool that held the pvc in place so he could drill another hole into the mast and pvc. He then filled to tool holes with rivets. ingenious, but I don't want to put more holes in my mast than it already has.

Mike

[Dale Tanski]

Risto,

If you go to the Maruska section of this site you will find a post with images regarding the masthead assembly.  It is not out of the question to modify the existing masthead to become an internal shroud arrangement.  If you would like we could do that for you.  Besides the modification to the masthead you will need to install exit plates to route the halyards back out of the spar. 

There is a extruded round slot on the interior of the mast that was used to secure the wiring bundle.  It is designed to fit a standard sail slug, I just can't remember which size off the top of my head.  The problem I encountered when I rewired and tried to use that slot was that along the way there were fasteners into that track and the slugs would not slide by.  I went the foam pool noodle route to keep the clang away.

Dale Tanski
Maruska
Hull #40

[Jim S]

I am posting a photo of the inside of the mast and a couple of the masthead crane.  Hope this helps.

[Risto and Liz]

  THANK YOU ALL,! Very helpful. Now, we'll see what I find when i get in there.
Seems like it might be quite a project to take the halyards internal. I'll post some pictures.

[Richard]

Sorry for the late reply.

I rewired my mast some years ago now and, as others have said, there is a slotted extrusion inside the mast.

I wanted my wiring not to "clang" inside the mast, so I tried various approaches to secure the mast wiring bundle.  I found that if I used normal plastic cable ties, the "nut" or square part of the tie would slide into the interior extrusion nicely.  These would secure the cable bundle from moving around inside the mast.

I rigged a line so that it came all the way down inside the mast from the mast head.  The other end of the line was led down to the base of the mast on the outside.  This was so that I could pull the wiring bundle back up the mast as I fed the cable ties nuts into the extrusion one by one.  I was able to pull the wiring bundle all the way up inside the mast this way with the cable ties sliding up the extrusion.  I recall that I had to experiment with the spacing of the cable ties.  If they were too close together, it was difficult to pull the bundle up the mast.

I also ran a couple of pieces of string up the mast in the wire bundle in case I wanted to run another wire (e.g., for a masthead wind speed sensor) at some point in the future.  (I have not had to use these yet.)

I hope this helps.

Richard
SV Water Spirit
P367