Patents for sailboat mast raising systems and telescoping masts (for nerds)

Jun 25, 2004
1,108
Corsair F24 Mk1 003 San Francisco Bay, CA
Hi all,

I did some online patent research recently on the topic of telescoping masts and mast raising systems. Reading them was fun. in a nerdy way.

Take a look especially, at US4016823, from 1977.
https://patents.google.com/patent/US4016823
# 4016823 is the grand daddy of all telescoping mast patents, by Robert S Davis. It was cited by virtually all subsequent applications for mast rasising and extending inventions that I found.

Here's a link to the list I generated. I compiled a list of relevant patents applications that were either pending, filed, or granted. I included both active and expired applications.
http://www.freepatentsonline.com/CCL-114-90.html
 
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vetch

.
Dec 3, 2011
111
Prout Manta 38 St. Augustine
That is interesting. I would assume it would have to be an unstayed mast just for simplicity. This one obviously sits on a tabernacle and hinges forward. I would be intrigued by a keel stepped design that sat flush or roughly flush with the deck when it is in the "closed" position.

I do like his system of elongated sail slugs, but a hoop system or a junk rig would also serve nicely. The addition of a infnatly adjustable forestay would let you have a jib but tensioning it would be not a problem but a constant process.
 

Jim26m

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Apr 3, 2019
579
Macgregor 26M Mobile AL
Thanks for posting that! A rabbit hole that branches off into a treasure trove of rabbit holes. Entertaining to see what folks think is worth a patent.
 
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dLj

.
Mar 23, 2017
3,373
Belliure 41 Sailing back to the Chesapeake
Can't see the significant advantage of a telescoping mast over a hinged mast. Don't see how it would be notably faster or easier to deploy than a hinged mast. It's certainly a lot more complicated. A hinged mast is simple, easy to fix, and leaves you with a pretty shear deck.

Just my 2 cents worth.

dj
 
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Jun 25, 2004
1,108
Corsair F24 Mk1 003 San Francisco Bay, CA
Thanks for posting that! A rabbit hole that branches off into a treasure trove of rabbit holes. Entertaining to see what folks think is worth a patent.
Yes, it's entertaining.

They all suffer from at least three out of four fatal flaws: Too complicated, too heavy, too weak, too expensive. That's why there's no commercially successful version of an extensible mast available.

Judy

PS. If you go down a rabbit hole, don't be surprised when you step in rabbit shit.
(Sorry, I couldn't help myself)
 

Jim26m

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Apr 3, 2019
579
Macgregor 26M Mobile AL
If it were designed such that the rigging retracted into the deck as the mast came down, and was all done with the push of a button, or at a single winch, it would be really nice in my opinion. I have a mast raising rig with locking winch, so raising and dropping the mast isn't that bad for me. However, once it's down, there is rigging everywhere. Then, I've got to disconnect the base and move it to the pulpit. Afterward I have to secure all of that rigging without kinking it. So, it ain't no walk in the park.

Unfortunately, the complexity, and appearance would be real factors. It's no good if not reliable, easily repairable, and as good looking as a standard mast.

I will confess to mulling over the idea myself, but have not come up with a concept that's worth even sketching. It would be a real design challenge.

I'm usually covered in a lot worse than what a rabbit leaves behind!
 

Jim26m

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Apr 3, 2019
579
Macgregor 26M Mobile AL
Wouldn't show it or talk about it until I had a patented, working, prototype. :)
 

dLj

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Mar 23, 2017
3,373
Belliure 41 Sailing back to the Chesapeake
Entertaining to see what folks think is worth a patent.
A number of years ago I worked for a company that built the fastest machine for one particular step in the process of producing patentable drug formulas. During that time, the major pharmaceutical companies were all in a race to produce drug formulas that they would simply patent even without doing any research into the effectiveness of the compound. They were doing this to have huge libraries such that if anyone found a particular compound that was successful, the company with that in their library could claim patent rights...

Amazing indeed what gets patented...

dj
 
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Aug 3, 2012
2,542
Performance Cruising Telstar 28 302 Watkins Glen
You found Tony Smith’s design utilizing solid stays. It seems to work well. I would like to recreate it, as my boat was built before he added it to production. I think Tony’s design suffered problem number 1: too complicated. The lower stays are actually struts that are tightened like turnbuckles. People have trouble tensioning them correctly, and they apparently bend them. It also uses two frames that can be removed as well as two sets of stays that remain in place.

Thanks for the search. I may end up building a hybrid, so my wife and I can handle less weight.
 
Aug 3, 2012
2,542
Performance Cruising Telstar 28 302 Watkins Glen
Which one is that? Link please.
My list had hundreds of links.
Thanks.
Which one is that? Link please.
My list had hundreds of links.
Thanks.
Darn it! Solid SHROUDS! The lower shrouds are more like struts or screwjacks.
Here is the link to the patent your site listed. I found the full document with photos and such a year or so ago.
http://www.freepatentsonline.com/7341014.html

I have been waiting to find another owner and get some photos and measurements in order to fabricate something similar, since I cannot find one to buy, although I have not looked lately. The company that produced the parts for PCI will not give up the drawings, even if I could get Tony Smith’s blessing.
It is a cool piece of rigging, and I don’t know why more boats did not adopt it. The fact that the Telstar was only in production a few years, numbering around 60 boats, may have limited the exposure of the system.
You can see it in action on a couple YouTube videos such as this:
 
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Jun 25, 2004
1,108
Corsair F24 Mk1 003 San Francisco Bay, CA
That's a brilliant design for a mast raising system on the Telstar 28!
I found this video. The mast lowering sequence starts at 8:32.
 
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Aug 3, 2012
2,542
Performance Cruising Telstar 28 302 Watkins Glen
That's a brilliant design for a mast raising system on the Telstar 28!
I found this video. The mast lowering sequence starts at 8:32.
Yup. I have watched that one and every one I could find. I have watched videos of the boat sailing to pause on shots showing the rig. The patent papers describe the process well. I understand all the movement and limits created by the struts. I would like to eliminate the C and D frames, which start the lifting motion before the “plate” reaches its limit on the forward side of the mast base. I think the mast could be started upward with just another line on the main struts. Also, the C and D frames are often removed for sailing. As you can see, the system works on land or on calm water. The most common problem seems to be bending the main struts, I think due to having them over-tight during lowering.
Now if I could get aboard a boat and take some pictures. I tried the company that manufactured the parts, but they stopped making them over 10 years ago, and they will not give up the drawings supplied by Tony. There is a users’ group, and I am hoping to get a look at a boat this Fall when I visit Florida.
All in good time. With patience, one will fall in my lap. Or I will fabricate one before then. Hopefully, I won’t step on anyone’s toes.
 
Jun 8, 2004
10,024
-na -NA Anywhere USA
@DrJudyB
Rabbit blank. I like Rabbit Bull fiddlesticks. Ha.

There are various systems using struts to keep the mast from swaying and so forth. I had talked with a few naval architecs, a couple of boat builders and mast manufacturers. We could not come up with a telescoping mast plus the cost to put onto an existing boat was prohibitive in cost. Keeping that information to ourselves vs. the public was suggested unless we had a proven economical system that we could tell the public. Thus nothing was said.
Interesting and thank you Judy.
Dave
 
Jun 25, 2004
1,108
Corsair F24 Mk1 003 San Francisco Bay, CA
I tried the company that manufactured the parts, but they stopped making them over 10 years ago, and they will not give up the drawings supplied by Tony.
Have you tried to contacted Gemini Catamarans Directly? Tony Smith? I’d guess that one of them holds the rights to the intellectual property and the drawings, not the company who fabricated the components 15 years ago.
 
Apr 5, 2009
2,774
Catalina '88 C30 tr/bs Oak Harbor, WA
I had a Catania 25 that had a crane built onto the front of the trailer that would raise the mast while rotating it to vertical and support it until the rigging was attached. There was a US patent placard on it but I wasn't smart enough to write down the number or take a photo during the time I owned it.
It worked great and I would love to find the Patent application but my search didn't find it.
 
Jun 25, 2004
1,108
Corsair F24 Mk1 003 San Francisco Bay, CA
We could not come up with a telescoping mast plus the cost to put onto an existing boat was prohibitive in cost. Keeping that information to ourselves vs. the public was suggested unless we had a proven economical system that we could tell the public. Thus nothing was said.
That makes good business sense to me , Dave. Why would you do it any other way? Until you have something to offer to the public, it would be silly to announce it.

If you couldn’t come up with a working prototype, there’s nothing to tell the public. If you had even a rough prototype, you would file an application for patent and probably still not disclose it to the general public because there no advantage to doing that. You wouldn’t announce it to the general public until you have developed to the point it was a proven affordable product and you were ready to sell it.
 
Aug 3, 2012
2,542
Performance Cruising Telstar 28 302 Watkins Glen
Have you tried to contacted Gemini Catamarans Directly? Tony Smith? I’d guess that one of them holds the rights to the intellectual property and the drawings, not the company who fabricated the components 15 years ago.
Yes. I called Gemini. Tony sold the company to his daughter and son-in-law. They do not have information, or are unwilling to discuss, anything pertaining to the Telstar. I do not blame them. It seems like a lot of trouble to go to. My next step was to send a letter to Tony at his listed address. I have not heard back yet. I will try another letter. I know he travels a lot.
The manufacturing company acknowledged that they do not own the drawings. They only fabricated the parts under contract. The owner said she would not give me the drawings even if I had a letter from Tony Smith. She said, “it would not be a very nice thing to do.” I am a little confused by the response, but I can let it go. No need to get into a power struggle with anyone. I will keep trying.
I will eventually get to fabricating the system, and I know the function of every part. It is the measurements that I will have to work out, but even those are basically right in front of me, since I own the boat. I may try simplifying it to not leave the struts in place, make them static and then store them onboard, maybe in the outriggers, maybe elsewhere.

Thanks,
Andrew
 
Jun 25, 2004
1,108
Corsair F24 Mk1 003 San Francisco Bay, CA
From a practical point of view, it's not obvious to me that it's worth re-emgineering a complicated system like Smith's system on the Telstar28. Re-engineering it looks like a lot of work to me, not to mention that you'll be doing some trial and error fabricating, with the risk of breaking something along the way. But if inventing and fabbing a new system resembling the Smith system sounds like fun to you, go for it. I'm not trying to try to dissuade you. Go for it.

A well executed system leaves little to good luck, chance and requires very little strength. The system that keeps you from damaging the boat or your joints is a well executed one. It doesn't have to be very complicated. The difference between a well executed system and a one that isn't well executed is like night and day.

For masts under about 40 feet, there are several examples of mast raising systems that you can build as a one-off with inexpensive components. These systems, are light weight and really safe, and easily maintained. The combination of a good mast crutch with a clever roller in the stern, a properly balanced mast with the spreaders in the right place, a gin pole with lateral guys with quick connectors can be built in a day or two or three (including attaching the deck hardware properly in a cored deck), I've built three mast raising systems over the years, and seen countless others on other sailboats and online.

The mast on the Telstar28 is only about 34.5 feet long. That's only a foot longer than the mast on my trimaran, and I put can raise and lower the mast by myself, even in a 20 kt side wind. It takes me less than 20 minutes from arrival at the launch to having the mast up and furler pinned, with the gin pole and stern mast crutch stowed back in the SUV. I'm a petite, 5'4" tall 67 year old woman. With two people we do it under 10 minutes.

What takes a long time when I trailer my trimarin is the job of connecting the boom, bending the mainsail slides onto the Tides Track, hoisting the jib on the furler, re-connecting the lazy jacks, running halyards for main, jib, spin and code zero through deck hardware, rigging reefing lines, connecting the outboard and gas, etc. I've got everything leading to the cockpit for single handing, more like a cruiser than a racer, and thats more work to set up than a minimally rigged daysailer. If all the lines stayed on the mast, it would save a ton of time. Having hanked on sails instead of furling would save time too.

Set up takes two people about three hours, from arrival at the ramp or crane to casting off from the dock, working at a comfortable pace without too many interruptions. Break down takes a little longer, because we have to coil all the lines. We have synthetic shrouds, which are much faster than wire shrouds to coil to coil for trailering.

I would never want to trailer and then daysail this boat. We trailer it to distant locations a couple of times a year for vacations and fun regattas.

Our mast raising system works on the water, but we haven't ever needed to do that. If we need to fix something on the mast, one of us goes up in a boatswain's chair. Trimarans are so wide and stable that a trip up the mast at the dock is easy, even if a wake from a passing boat hits us.

Judy
 
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