Mast Refit - access holes/plates & conduit

[alaskanviking]

Currently in the process of refitting the mast. Stripped the paint and just finished sanding last night. We are completely bare metal now, and ready for the pre-paint metalwork.

My goal is to set things up so I can replace any wiring or coax as required without having to pull the stick again. The boat was not set up that way. The wiring and conduit I had installed in San Diego was disappointing, and I pulled everything and am starting from scratch. As such it's led to some questions.

Problem 1) there isn't an wiring access hole)cover plate at the bottom of the mast. There is literally no way to snake wiring down. Even pulling the wires back out with the mast down was difficult.

I found a Kenyon spars, stainless steel elec access plate cover on rigrite. It's 4.5"x2" and covers a 3"x1-1/4" hole. I was thinking about having the rigging company fabricate curved covers out of 1/4" aluminum so there is limited electrolysis.

I searched all over in access plates and there is limited info. Found a couple pictures, definitely done for deck mount masts. I didnt see anything on keel stepped masts, other than possible vague references.

Its not a big hole, is there any reason I couldn't add an access hole at the bottom of the mast?

Extrapolating off that idea, it makes some sense to add an access at the top of the mast as well. What about the spreader and or radar area to make it easier to run wires, do maintenance or replace a cable altogether?

Some of this is alleviated below.

Problem 2) I pulled the conduit that was installed. It's too small, 1". Part of why it was difficult to move/pull wires. Definitely not feasible that way to pull or add wires or change equipment later ect. On the plus side all the rivet holes are there already in the correct position. I'm leaning towards putting in a 1.5" conduit here.

Looking up and researching conduit install. I found a lot of conflicting information. As installed I can't access or feed the top of the conduit if the mast was up. I realized I may be able to bend some aluminum tubing sized to fit over the PVC, drill a hole in the top of the mast head to fit, and run this tube down to recieve the PVC conduit. Weld the top to the mast head and reinforce with a rivet or two along the length. The idea is to make a continuous length of conduit to the mast head and alleviate the need for an access hole at the top. Should be easy to snake a wire through to the bottom, with the mast up.

Am I off base here or am I on a good track here?

Problem 3) It's a Kenyon cruising section spar. There is a wiring channel as part of the mast, covered by a luff track that the main sail track is on. The only way to pull the luff track is if the mast is down. At the top, spreaders, radar ect there are small holes inside the wiring channel to run wiring to the spreaders ect. Because the 90 degree angle the wire takes to transition from the channel to the spreader/radar ect you can't pull or replace a wire unless the luff track is off. So if you replace the radar you can't replace the cable. I tried you couldn't get the cable out let alone back in even with a tag line. Adding stuff, no way. The other issue here is the halyard sheeves are above this at the top of the mast so wire and cables have to be snaked around to the wire holes in the mast Head where they won't interfere with the halyards (or vice versa)

The rigger in San Diego installed a PVC conduit to ~ 2' from the top, and a second for the radar (too short). Since I'm redoing this I will increase the length of the second conduit. I believe the 1" PVC they installed would still be a good size here. Should I add a right angle to the top of the conduit to make it easier to run the radar cable?

The wiring holes for the spreaders are closer to the back of the mast, the conduit is close to the front. If I run the spreader wires using the mast wiring channel they are essentially not removable. If I wanted to install or replace an spreader attached antenna I couldn't once the mast is up.

I was thinking of running a third conduit riveted to the underside of the wiring channel. 1-1/4 maybe. Use a PVC T fitting for the first spreader. The rivets would be countersunk so nothing could catch. Use that conduit solely for the spreaders.


For the top of the wiring channel I was thinking about bending some more aluminum tubing to fit between the top part of channel and the top of the mast head. Weld at both ends ( I am having other welding work done to the mast head). This in theory would ensure cables would be channeled away from the sheaves and halyards and give a smooth easy pathway for cables, and would allow for antenna cable replacement with the mast up if required later. I was intending of using the channel solely for antenna cables to the mast head.

Is this a good plan or am I adding to much work here for to little benifit?

Problem 4) the rigger in San Diego installed the conduit using metal ducting tape to connect the sections. It was a bit floppy, but it's ultimately riveted in place.

Is tape a good solution here?

Why not just glue on PVC coupler fittings, or but the 10ft sections with a molded in coupler?

There are also inside the tube style couplers. A bit more expensive and takes up some of the space ID for wiring but with a 1.5" tube I don't think that's as big of a deal. Would make the outer diameter the same vice couplers which would have a bump at every connector (not sure if that matters, the rivets should suck that in).

Is an inner coupler or an standard PVC outer coupler a better fit for this application?

Problem 5) the masthead wiring simply goes through holes in the top of the masthead. There is no way to prevent water from draining down through the holes. Im fairy certain that some of the corrosion at the mast step and bottom of the mast was due to the mix of stainless and aluminum and regular rain water. Was light corrosion easily fixed this time, but I'd like to prevent that as much as possible.

Once (if I follow plans above to weld conduit tube into top of mast head), I have the conduit installed through the mast head, what is the beat way to prevent water from running down the tube? Is it as simple as adding an elbow at the top of the conduit tube? Just add a multi cable damm over the top?


Is there anything that I'm missing? Should think about adding/changing?

Thank you

I know, it's a long post. Been saving up questions and they all came to a head when I finished sanding. Again the goal is to set up for the future, I'd like to replace wiring and cables or replace/install equipment without having to pull the mast. Attachment 250529

[mike d.]

Hi Alaskanviking! So our mast, 1979 Gulfstar 37 mast there are exit holes for the mast wiring, just below the sole access plate, around the mast ! The exit hole is o0n the port side,as the terminal block is mounted on the port side of the mast, on a beam/sole support, just under the cover for the access hole ! The wires (numbered) coming out of the mast, attach to the terminal block (numbered) according to each feed !

[Mbramanti]

guys any reccomendation for grounding a mast for corrossion prevention?