Ways to Add 6ft to the BOTTOM of a mast?

[Aethelwulffe]

Resorcinol or even plastic resin glue, or yes, your TightBond#3 beats out epoxy there every time, and in any tight joint, but it looks like we are talking aluminum extrusion.
RE:Robertmfranlin Yes, sleeves must be fastened at the ends and the middle. No, the spar need not look like swiss cheese, but masts are not pure compression members, or they would be square (for reasons other than wind resistance) and micro-scale movement will cause wear in the joint, corrosion as anodization wears off etc. Yes, a bunch of stainless screws in your aluminum mast is a bad idea, and rivets fill and compress the hole completely vs. how sheet metal thread treats it, but I would not say you screwed up.

[Aethelwulffe]

Yes, I read where you posted you calculated the rig parameters. Until those are realized on a "Custom" boat, I assume it to be theoretical, so gimmie a little leeway? I really didn't wanna poop on your parade. Nobody, like nobody needs any extra crap these days.


May I suggest if you are done with a thread you originated, but folks wish to entertain themselves with its dead horse, maybe that isn't a bad thing? You inspired a discussion, got what you wanted, and you ain't responsible for any further idiocy displayed, right?
-Fair Winds and Following Seas, unless you prefer sailing hard and by, in which case, I wish you happy reefing and clean scuppers!

[Catalier]

Anyone can do anything at all, if they’re willing to learn.

Amen brother. I've swaged some standing rigging, ran new electrical wiring, installed a wind vane, preformed 3 abortions, swapped my lead acid batteries for lithium, ect,ect - all just following youtube videos. People dont want to do anything for themselves anymore. Joshua Slocum would roll over in his watery grave. SMH my head...

[Chotu]

Originally Posted by OneBoatman

Based on the date of your question you've probably already done what you thought is best. I wouldn't think just extending your mast 6ft from either end is such a good move because while you've considered the obvious things you have to change there is no doubt a couple you haven't considered. Since you you want to raise the gooseneck I wouldn't even consider extending from the top as this means you must relocate the gooseneck. Thus sleeving and extending from the bottom is the more logical choice. Don't overlook the extra cost to re-wire any lighting and instruments you have at the masthead, longer halyards and topping lift, clearances for a longer kicker, new stays all around and added sections of furler foil. Are you going to buy a larger jib or simply fly the one you have higher? Remember the raised location of your top swivel effects the lead angle to the turn at the crown and these must be such to prevent halyard wrap. If you go with at bigger jib in a desire to take advantage of the now bigger foretriangle this could result in reducing whatever pointing ability your cat already has and could give you unneeded trouble "getting the bow around" each time you tack. I would contact the builder/designer, if they are still available, and see what they have to say about the change before you play marine architect. Sail on sailor.

Are you kidding me??

Is this just trolling now???

[Chotu]

Originally Posted by Catalier

Anyone can do anything at all, if they’re willing to learn.

Amen brother. I've swaged some standing rigging, ran new electrical wiring, installed a wind vane, preformed 3 abortions, swapped my lead acid batteries for lithium, ect,ect - all just following youtube videos. People dont want to do anything for themselves anymore. Joshua Slocum would roll over in his watery grave. SMH my head...

Right???

I have a word that’s definitely not permitted on the forum that’s coming to mind regarding these folks. It’s a synonym for cats. Ha ha ha.

More importantly than name calling, how do these people expect to know their boat well enough to be self sufficient away from land when they aren’t even self sufficient at the dock?

Boggles the mind.

The “Can’t Generation”

A lot of people would be rolling in their graves at what we’ve become

[Manateeman]

As always I recommend Principles of Yacht Design by Larsson. Look at all the previous discussions on boat design.net . This is not brain surgery.
1. You do not absolutely need to find an original section. The sleeve can be fabricated in 2 halves on a brake at any good shop. OR, you can use the existing extrusion to build a mold and lay up a sleeve in any method you like. It’s nice to have a perfect sleeve, but not necessary. If you have an extrusion, you can construct more extrusion out of aluminum or glass or carbon fiber.
2. Tabernacle. What’s so difficult about this ? The boat is under construction and if you want to have a tabernacle, this is the time to do it. I would not increase the mast length on my boat, but it’s your boat. Lots of gloom and doom posted but just stick to the engineering...get a second opinion. Post on design net as well.
Find a good aluminum TIG guy. Buy a lot of Plexus.
I kinda think you’ll end up with a nice rig.
Manatees are neither fat nor slow...just good looking and cruising along.
Happy trails to you.
Captain Mark and his crew of beer can boatbuilders.

[AKA-None]

The strength is in the sleeve not the welds so a bit longer than a couple of feet as some suggest is to short.

The op sounds like he has it figured out but just wanted to so if there might be other options.

[Chotu]

One of the few posts understanding the problem and solution was made by the ONLY professional rigger to have posted in this thread.


My closing comment is a quote I’ve always lived by:

No matter if you think you can, or you think you can’t...



you’re right!

[smj]

Originally Posted by Chotu

One of the few posts understanding the problem and solution was made by the ONLY professional rigger to have posted in this thread.


My closing comment is a quote I’ve always lived by:

No matter if you think you can, or you think you can’t...



you’re right!

I absolutely agree with you, with a little perseverance one should be able to do just about anything.
At times it is nice to hire a professional as they are usually quicker at getting the job done. An example would be our boat and all the different shapes and angles. I decided it would be better to hire a professional to take care of the hanging, taping and floating of all the Sheetrock. I’m glad I did because even he said it was a challenge.

[GRIT]

I assembled this mast myself. It came from Selden, in Charleston, and was designed for my boat specifically. It's not cobbled together, or made to "make do". I'd have loved to have a single piece mast, but they arrive in the USA as blank extrusions, and are made to fit in a 40 foot container. The splice is entirely Selden's design, and comes with an "assembly manual".

The mast is 64 feet long, and was designed for an 80m2 mainsail and a 37m2 jib. The boom is 21 feet long. The mast is not massive, but not tiny either. It's likely very similar in dimensions to Chotu's mast, as we built our boats from the same design, and therefore have similar requirements.

I doubt this splice is more than 2 feet long. By memory, it was a few inches under 2 feet. It has a few rivets, but mostly machine screws.

I'm sure there are many ways to skin this cat, but it appears that the splice doesn't have to be very long. Nor is it a requirement to use welds; or a crime to use machine screws.

Chotu: You're motto is spot on. If you think you can, you can. If not...not.

Cheers all.
Paul.

[GRIT]

SMJ, did you mean house? I've yet to see a boat with sheetrock.

If so, congrats on building your own house. (minus the sheetrock. )

Cheers.
Paul.

[smj]

Originally Posted by GRIT

SMJ, did you mean house? I've yet to see a boat with sheetrock.

If so, congrats on building your own house. (minus the sheetrock. )

Cheers.
Paul.

That was my misguided attempt at humor!
I build houses for a living and the 2 things I don’t do are Sheetrock and roofing. Both very hard work and both accomplished much faster by the professionals!

[AKA-None]

Originally Posted by GRIT

I assembled this mast myself. It came from Selden, in Charleston, and was designed for my boat specifically. It's not cobbled together, or made to "make do". I'd have loved to have a single piece mast, but they arrive in the USA as blank extrusions, and are made to fit in a 40 foot container. The splice is entirely Selden's design, and comes with an "assembly manual".

The mast is 64 feet long, and was designed for an 80m2 mainsail and a 37m2 jib. The boom is 21 feet long. The mast is not massive, but not tiny either. It's likely very similar in dimensions to Chotu's mast, as we built our boats from the same design, and therefore have similar requirements.

I doubt this splice is more than 2 feet long. By memory, it was a few inches under 2 feet. It has a few rivets, but mostly machine screws.

I'm sure there are many ways to skin this cat, but it appears that the splice doesn't have to be very long. Nor is it a requirement to use welds; or a crime to use machine screws.

Chotu: You're motto is spot on. If you think you can, you can. If not...not.

Cheers all.
Paul.

Interesting I stand corrected

[GRIT]

Aka...you wouldn't believe how many times I've stood in that same spot.

Cheers.
Paul.

[stubones99]

Is your current mast keel stepped or deck stepped?

If it is keel stepped, simply have a NA design a compression post to convert it from keel stepped to Deck Stepped, and there would be about 6' of extra height.

If I were doing an extension to a mast, I would hire a good welder, use an excess section of the new mast to build an inner splice to fit down inside the new and old mast tubes, and slot weld it to the old mast, and a weld around the junction and it should be as strong as the rest of the mast.