Wow! Custom Masts? What to do??

M25max

Member
I finally got the sail and booms out and I looked at them and I found some strange stuff. Remember I had this boat inspected prior to purchase by a “knowledgeable Sunfish guy”.

I found both booms to have extensions in them, but are the correct overall length. The gooseneck looks funny and is placed at 38.5” from the front of the lower boom. The two blocks for the mainsheet are lashed onto the boom and are at 99” and 140.5” from the from of the lower boom. The sail is held on with cable ties (luckily at least I have new sail ties).

What do you guys think? Did Sunfish in the 1960’s use booms with extension pieces? Is the gooseneck original or another custom machined part? Did the 1960’s boat have the mainsheet blocks lashed to the lower boom or where them held on my riveted on straps? Should I buy new booms?

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The mast is fine. The mast is the right diameter, length, wall thickness, and I put new top and bottom plugs in it.
 
I found both booms to have extensions in them, but are the correct overall length.
Looks like the lower boom has a newer anodized sleeve over it. This "sleeve" must run all the way to the tack because notice how the lower boom appears to be larger diameter than the gaff where the two come together at the tack. At least it does in one photo. In the other, not so much.

Maybe the original lower boom had corrosion that was bad enough that it needed to be sleeved. Or, the lower boom was broken and either outer sleeved all the way forward or replaced completely with larger diameter tubing with just a section of the original boom at the clew end.

The boom combo may be just fine, stronger even, but I'd try to take it apart just so I'd know what had happened and what the current conditions are inside the sleeve.

- Andy
 
Looks like the lower boom has a newer anodized sleeve over it. This "sleeve" must run all the way to the tack because notice how the lower boom appears to be larger diameter than the gaff where the two come together at the tack. At least it does in one photo. In the other, not so much.

Maybe the original lower boom had corrosion that was bad enough that it needed to be sleeved. Or, the lower boom was broken and either outer sleeved all the way forward or replaced completely with larger diameter tubing with just a section of the original boom at the clew end.

The boom combo may be just fine, stronger even, but I'd try to take it apart just so I'd know what had happened and what the current conditions are inside the sleeve.

- Andy
It isn’t a sleeve. The extension only goes a couple inches into the rest of the boom.
 
It isn’t a sleeve. The extension only goes a couple inches into the rest of the boom.
That's why I put quotes around the word "sleeve" in my post. It's a sleeve in name only.

What I'm wondering is, if that new tubing runs from the tack all the way to the extension, why did the person who did the work not go all the way to the clew with the new tubing? It's not like they were saving on hardware at the clew by keeping the end of the old boom.

- Andy
 
That's why I put quotes around the word "sleeve" in my post. It's a sleeve in name only.

What I'm wondering is, if that new tubing runs from the tack all the way to the extension, why did the person who did the work not go all the way to the clew with the new tubing? It's not like they were saving on hardware at the clew by keeping the end of the old boom.

- Andy
The tube that extends out from the end is smaller diameter tubing than a Sunfish mast. I wish I knew. The boom does not have any corrosion in it at all. Very clean.
 
The extension only goes a couple inches into the rest of the boom.
Personally, I would feel more comfortable with more overlap of the old boom end and the newer, larger diameter tubing than a couple of inches.

If it was just compression load from outhaul tension along the foot of the sail that would be one thing. But there's a lot of leach tension loading pulling up on the end of the boom when you're sheeting in hard.

- Andy
 
The tube that extends out from the end is smaller diameter tubing than a Sunfish mast.
Ah... very interesting. I'm getting a better idea of what you've got now. BTW, you meant to say, "Sunfish boom", right? :)

In any case, you may want to take the lower boom off the sail, support the very ends of the boom with saw horses or something, stand in the middle of the two ends and slowly load up the boom with some of your body weight.

Check out the flex pattern of the entire boom. If the arc is nice and continuous at the junction of the smaller diameter extension, then you may be ok. But if there is a noticeable angle change at that junction, then you need more overlap of the larger and smaller tubing.
 
The two blocks for the mainsheet are lashed onto the boom and are at 99” and 140.5” from the from of the lower boom.
The reason the two blocks for the mainsheet are lashed on to the boom is because your new, clean boom (with the "extension" at the end) is not a stock Sunfish boom. The stock ones normally come with two mainsheet blocks attached to stainless steel strap eyes that are riveted to the boom.

But having those mainsheet boom blocks lashed to the boom is ok. I have mine lashed to the boom as well. You just want to make sure they are at or near the position of the stock riveted ones. You should be able to find the measurements of where those stock ones are located somewhere. Also, someone here on the forum with a new boat could get those measurements from their boat to you.

By the way, make sure you get those measurements from a newer boat because the stock location for the forward one is now closer to the front of the boom than in years past. Positioning that lashed forward boom block right over the mainsheet block that is mounted to the deck is a good start for now.

Once you have those lashings in the right position, take some white electrical tape and wrap the boom in front of and behind the lashings until there's a bump of built up tape. These bumps/ridges will keep the lashings in place because they will want to wander up or down the boom depending on where the most forces are pulling them.

Cheers,

- Andy
 
The sail is held on with cable ties (luckily at least I have new sail ties).
Yes, you are going to want to replace all those cable ties because they are holding the sail a bit too close to each boom. Here's a photo below of the position that your sail ties/rings will be holding the sail (the luff in this case) relative to the boom. This photo is from a Sunfish racer's set up... so you know it's just about perfect. :cool:

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And then there is the cable tie outhaul. That's a first for me. Cut it off and here's how you want your outhaul to look.

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First, the actual outhaul which is the pink line (Dyneema). This is again from a race boat set up so this is actually an on the fly, while you are sailing, adjustable outhaul. The rest of the pink line that goes up to the cockpit is hidden behind the boom. However, you and your daughter don't need an on the fly adjustable outhaul. But this photo represents just about what you want. You've got a loop (bowline) around the stainless steel grommet at the clew of the sail, then back and forth through the black end cap, through the grommet again and then, unlike this photo, the end tied off here.

I don't know if you've got the room on the end of your boom but it's ideal to have some space between the grommet and the black end cap which allows you to have enough line going back and forth to periodically adjust the outhaul tension on the sail. On light days you can take just a few minutes, loosen the outhaul for more power then tie it off again. If there's more wind, tighten the outhaul. You don't have to use Dyneema. Any low stretch line will do.

Finally, there's the purple line. This line keeps the position of the clew fixed relative to the boom. Just off of it. Having this purple line allows you to very precisely control the leech tension in the sail. If you don't have this purple line, when the sail loads up the clew will rise up off the boom and that loosens your leach tension.

Your sail has this purple line in the form of a cable tie. But that cable tie is too tight. Cut it off and copy what you see in the photo. And you are going to want to do the same thing where the sail is tied off at the very top of your luff on the upper boom. This will allow you to periodically adjust the luff tension of your sail just like your outhaul.

I point out these set ups because your daughter may be a little light for the Sunfish so she'll want to be able to pull as much power out of the sail when it's kind of on the windy side while also being able to loosen these two so she has as much power as possible on very light wind days.

Best,

- Andy
 
Ughh, the cable ties were so tight that you couldn’t move the sail on the booms.

Well, luckily today a local shop had a used upper boom (a little bent, but OK) and a new/lightly used race boom. I bought them without hesitation after the feedback here. I have dyneema sail ties I can use to install the sail to the booms I bought. I believe this story is having a solid resolution. I assume with the racing boom the Sunfish will now be able to terrorize the other boats on the lake.
 
To confirm what others have said, the booms in your photos are not stock Sunfish booms. The end caps and gooseneck are the giveaway - not genuine Sunfish gear.

Some of the Snark brand sailboat spars used inserts probably to make them longer than stock length tubing. I have a set of Snark Mayfower spars configured like this. The inserts are like aluminum tent poles with the outside diameter of the insert is the same size as the inside diameter of the longer tube. Pretty ingenious actually. Some people have repaired damaged spars by cutting out damaged sections and rejoining them with wood dowels and some epoxy or screws. If you had some of these inserts, the repair job would be better and easier.

It goes without saying that these "Sunfish" spars would probably not be Sunfish Class legal for racing in sanctioned events. I can sell you a set of genuine Sunfish Class legal booms, $40 for upper booms and $45 for a lower boom with blocks, but they are pick-up only in Cazenovia, NY near Syracuse, NY. Also have nice reconditioned bronze goosenecks for $45.

Alan Glos
Cazenovia, NY
 

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