Kenyon mast

[kath]

My Ericson 34 has a Kenyon mast with a track to put the main sail slides into. When I tried to raise the main sail
it got caught on the top screw holding the track in place. When we got to the mooring I hoisted my friend up the mast
and he said the screw was sticking out enough to stop the slide. However, he couldn’t tighten the screw. My question is do
I have to take down the mast to fix this problem? Has anyone else had this happen and if so how did you solve it?
The good news is we had a lovely sail with just the genoa.

 

[mjsouleman]

Hi Kathy,

I assume the screw head was not stripped because your friend said he couldn't tighten it.
Option 1: the screw maybe rusted a good soaking with penetrating oil and a day or two to penetrate the rust.
Option 2: while hoisting the sail, the screw twisted and the threads are jammed.

Neither are insurmountable, just need the right tool to grab the screw. Once you get it out, you will want to tap the mast threads with a tap (see link).

Carbon Steel Metric Tap and Die Set, 40 Piece

Amazing deals on this 40Pc Carbon Steel Metric Tap And Die Set at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

Mark "Souleman" Soule

 

[Prairie Schooner]

I should think it's something a competent rigger could do in the air. Taking a mast down is Very expensive, at least at the yard we used.

 

[kath]

Hi Kathy,

I assume the screw head was not stripped because your friend said he couldn't tighten it.
Option 1: the screw maybe rusted a good soaking with penetrating oil and a day or two to penetrate the rust.
Option 2: while hoisting the sail, the screw twisted and the threads are jammed.

Neither are insurmountable, just need the right tool to grab the screw. Once you get it out, you will want to tap the mast threads with a tap (see link).

Carbon Steel Metric Tap and Die Set, 40 Piece

Amazing deals on this 40Pc Carbon Steel Metric Tap And Die Set at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

Mark "Souleman" Soule

Thanks Mark. I think the screw just turned but didn’t tighten. He said he couldn’t even get a fingernail under it. He thought maybe there was supposed to be a bolt behind it. I’m going to ask him again when I see him. He tried to tape it flat but the slide just jammed on the tape.

 

[Marlin Prowell]

We have an Ericson 34 that had a similar problem. The mast track has two sections with a splice that is just below the first spreader. There is a machine screw on either side of the splice holding the track to the mast.

This spring we were unable to raise the main past the splice in the mast track. On investigation, I found the head of the lower machine screw had snapped off and the bottom segment of the track had wiggled slightly out of the mast, so no longer in alignment with the upper track segment.

I used a small nail to feel inside the hole where the screw had been and could tell that the shank of the machine screw was still embedded in the mast. Stainless steel screws into aluminum eventually corrode and I could see some white powder indicating that the screw and mast had corroded. There was no way that I would be able to remove the screw shank through the hole in the mast track.

As it happens, our next door neighbor at the marina has an Ericson 35 with a Kenyon mast, and I asked him if he ever had a problem raising his main. He said he has the problem every spring, and just goes up the mast and hammers the mast track segments back into place! Sometimes he has to do it during the sailing season. Both machine screws of his mast track are missing, so he's depending on a tight fit between the track and the mast to keep things aligned.

To solve this for our boat, we installed a Tides Marine SailTrack system. There's lots of information about this system on this forum. We don't want to get trapped with a main sail that I could not lower because the mast track had again popped out of alignment. Even if a track segment gets slightly loose, the SailTrack spans the splice and prevents misalignment.

In your case, I don't think that rust is the problem. This is a stainless steel machine screw into aluminum. Instead, corrosion is the problem, and, if the screw spins freely, the threads in the screw or the mast have corroded away.

There is no nut on the inside of the mast to hold the machine screw. This would be impossible to install even at the factory. The mast track splice is at least 15 feet from the end of the mast and there is no way to securely hold and position a small nut that far inside the mast. The machine screw for the mast track is held via threads cut into the aluminum mast.

You MIGHT be able to drill out the existing hole in the mast and tap larger threads for a bigger machine screw. This assumes that there is enough good aluminum that hasn't corroded for tapping new threads. You'll also need to drill a larger countersunk hole in the track for the larger head of the larger machine screw. If you do this, be sure to use Tef Gel to help prevent corrosion in the future.

 

[kath]

Thank you so much for all this valuable insight. I’m not sure how to get the machine screw out but if I do it might be worth trying to tap larger threads for a new machine screw. I’ll google the Tides Marine Sail Track system but it might be too much for me to tackle right now.

 

[peaman]

I'll google the Tides Marine Sail Track system but it might be too much for me to tackle right now.

The track is one part, but it also requires replacement of all of the luff slides. I recently went this route and am happy with it. But I can't use my spare 2-reef main until I get new slides installed.

 

[Kalia]

On my E-342, when corrosion caused these screws to fail, I replaced both screws holding the two mast track sections together. I had someone winch me part way up the mast in a bosun's chair and I drilled and tapped a new hole just above the embedded remaining section of the original machine screws. Drilling and tapping into the remainder of the stainless steel screw which is surrounded by softer aluminum is really not feasible. Especially since you can't see where you are drilling into the back of the mast section as the drill bit goes through the screw hole in the mast track. Using a slightly smaller screw head meant that even though the screw was not perfectly horizontal, the screw head was fully buried into the mast track and the sail slides pass over without restriction. Since the mast wiring also uses this channel to go up to the masthead light and deck lights, I used a small length of riggers tape on the drill bit so that it wouldn't cut the existing wires. I also used a short length of stainless steel wire to hold the mast wiring out of the way of the drill bit using the second track hole for this temporarily.