Securing wiring inside mast

[SVTatia]

Originally Posted by pwillems

I just did both my masts (very big schooner) running conduits all the way up. I'll share my method as I feel it was very easy and it may help others.

With masts lying down, I prepared a length of PVC pipe cutting large holes at the required positions where wires would need to be fished and exit mid mast. I then positioned the mast so that gravity would hold the inserted PVC in position up against the ridge formed by the sail track in the inside of the mast. When everything was ready, I simply slid the pipe up the mast putting a glob of adhesive (liquid nails) every meter of so, therefore smearing it as the pipe was pushed up the mast.

I let this sit for 24 hours so the adhesive would go off, and then, using minimal pressure drilled through the mast and PVC (now reasonably secured inside the mast) every meter in preparation for rivetting once all the wires were run.

I then ran all my wires and once happy everything was finished off properly, popped a rivet in my pre-drilled holes to make sure it never fails.

I'm not sure how long the adhesive will last, but it does not matter, it's purpose was only to secure the conduit during drilling and wire insertion. The rivets are the ultimate fasteners.

Thank you pwillems to contribute with your technique, a variation of Capacabana's.
The adhesive will be redundant once the pop-rivets are in, but it served its purpose and should last since it is not under any stress.

However, I do have a couple of 3 questions (would that make it 6?).

• What did you use on the outside of the mast as a reference to drill the holes? Mast track, I assume, and did you draw a line?
• How far apart did you space the holes?
• Why did you pop-rivet only after the wires were pulled?

[Cheechako]

I've often wondered if those pool noodles wouldn't be great for this when there is no conduit in the mast.. The thick ones. Your halyards are not internal?

[capt jgw]

Originally Posted by Cheechako

I've often wondered if those pool noodles wouldn't be great for this when there is no conduit in the mast.. The thick ones. Your halyards are not internal?

Good idea. I use pool noodles on my mooring lines, they make the lines easier to see (bright yellow) as well as float. With UV exposure they only last one season, but should last pretty much forever inside the mast. I get mine at Dollar General for, of course, a dollar. As I remember they're 4 feet long. You could use pipe insulation but it's not as thick and costs a lot more.

[chouliha]

Originally Posted by sethjohns

I do like the blocks of foam concept best. If you use closed cell flotation foam, if the boat were to turtle in a knockdown the flotation will add a leveraged writing moment to the mast.

A word of caution regarding using foam. Years ago I worked on a mast that had foam inside and moisture was trapped between the foam and walls of the mast creating lots of corrosion. Not sure if the mast was inferior metal or ?

Also I pulled a number of wires out of existing masts that had conduit inside held with pop rivets and never saw any sign of chafe.

LOL you certainly have enough ideas to chew on......

Good luck with your project

Chuck

[pwillems]

Originally Posted by SVTatia

• What did you use on the outside of the mast as a reference to drill the holes? Mast track, I assume, and did you draw a line?

Correct, I just used the mast track. There was no need for line, I simply looked inside the mast, saw that the holes would need to be about an inch from the edge of the track and drilled my holes accordingly.

Originally Posted by SVTatia

• How far apart did you space the holes?

I did them at 1 meter intervals.

Originally Posted by SVTatia

• Why did you pop-rivet only after the wires were pulled?

After drilling the holes, I used a length of 3mm stainless cable with a string taped on at the end of it. I pushed cable and string through the pipe from the bottom, fished out the string at the top, removed the tape and used the string to pull through each wire. Had the rivets been in before pulling, I'm certain it would have caused trouble with snagging cable or string along the way. Easier to get all the cables fully pulled first and rivet after.

[ahun]

Working on the same problem, again...

This is the old conduit in the mast, with the failed pop rivet and the damage it caused to the wiring. And that's at the bottom of the mast!