Tabernacle(s) for Mast

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Tabernacle(s) for Mast

Tom Altee
I'm looking for advice in building or buying a tabernacle for raising or lowering the mast on my Kismet. As you can see from the photograph provided there is a wood block attached to the cabin roof for the mast to be raised on.  I have not had the mast raised at this point in ownership.  The mast will be back soon from the boatyard after having been buffed out and repaired and will be set up.  Any advice or direction to a plan for building a tabernacle will be greatly appreciated.
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Re: Tabernacle(s) for Mast

Perry
This post was updated on .
There's details on how to build on on the Seahawk website. I handed the details to. Steel fabricator a while back, and they said they could easily make one from the plans

The only gotcha was going to be the mast pivot, as it needed aluminium welding. However a friend said he could cut a nylon bush on a lathe and we could press fit it, do all done

Let me know how it goes.  Your boat is an inspiration!

Thanks

Perry

Sent from my iPhone
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Re: Tabernacle(s) for Mast

GregSeaHawk
Administrator
In reply to this post by Tom Altee
Hi Tom,

As far as I know the wooden block is not original equipment, although I have seen a few boats with such a fitting. I'm not sure of it's function, unless it's to cover some earlier damage to the cabin roof.

I have a post on the forum showing my original mast step and the main site has a page with details of my tabernacle.


Greg Chapman
GregAfloat - My Boating Biography
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Re: Tabernacle(s) for Mast

Tom Altee
In reply to this post by Perry
Found the info on the tabernacle.  Thanx Perry!
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Re: Tabernacle(s) for Mast

Tom Altee
In reply to this post by GregSeaHawk
I will take a closer picture of the wooden block and have it up tomorrow.  Thanx Greg!
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Re: Tabernacle(s) for Mast

brian johnson
This post was updated on .
In reply to this post by GregSeaHawk
I agree with Greg on the wooden block.  Any damage to the roof must be sorted asap as it is a balsa sandwich construction so any water ingress will rot the balsa, weakening the roof.   So carefully bed the tabernacle on to mastic like Sikaflex etc.
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Re: Tabernacle(s) for Mast

GregSeaHawk
Administrator
Hi Tom,

I've done a quick search through my collection of SeaHawk photos and found this:

Tabernacle Mount

It shows a "recent" Mistral Craft boat that appears to have a tabernacle designed for a boat that has a sloping cabin roof and isn't quite tall enough for a SeaHawk.

So far, apart from this and yours, I haven't found a photo with another with a wooden block at the mast step, though I recall I had seen another in the past. I'll keep looking.
Greg Chapman
GregAfloat - My Boating Biography
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Re: Tabernacle(s) for Mast

GregSeaHawk
Administrator
Hi Tom,

I've now been through my entire collection SeaHawks photographs - more than 130 boats. Not all include views of the mast step but of those that do and that's the vast majority, there are only two additional ones that have any form of mount for the mast step:

Tabernacle Mount

Tabernacle Mount

The exercise confirms my impression that SeaHawks were never delivered with a wooden block at the mast step.
Greg Chapman
GregAfloat - My Boating Biography
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Re: Tabernacle(s) for Mast

Perry
This post was updated on .
Just so you know, I have what looks like an identical block at the bottom of the identical kind of mast foot.

Can you post a closer picture?

Thanks

Perry

Sent from my iPad
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Re: Tabernacle(s) for Mast

GregSeaHawk
Administrator
Hi Perry,
Perry wrote
I have what looks like an identical block at the bottom of the identical kind of mast foot.

Can you post a closer picture?
If you're referring to the blue boat, that's Reed Nibbler and the image is already enlarged from the full frame version seen in the gallery and taken ten years ago, so I can't do better for you.

I know you sent me some photos of your boat. The external ones show the cabin under a tarpaulin, but you may not have encountered the only other pictures I have of your boat, also sent to me around ten years ago

It appears that back then it did not have a wooden block under the mast. Here's an enlarged version...

Piccolo
Greg Chapman
GregAfloat - My Boating Biography
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Re: Tabernacle(s) for Mast

Perry
Greg

It's amazing how easily memory can play tricks. I just checked and you are right

It's a completely different boat I was thinking of, and it was one transposing over the other. Must be an age thing!!!

I'll send you a couple of updated photos, and when I start the renovations in earnest, will keep you up to date

Thanks

Perry

Sent from my iPhone
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Re: Tabernacle(s) for Mast

Freedom
dear all,
coming period I would like to have a tabernacle as well. maybe next year, but I can start already. I have a question about the 4 bolts (picture of the tabernacle in the description of the modification) through the basement, roof and wooden block (inside against the roof). Do I really need those 4 bolts? and if yes can somebody give measures (as for holes in the basement of the new tabernacle); the widt; I presume the length is the wooden block; the roof and the basement of the tabernacle + two times the screw thickness?

thanks in advance.
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Re: Tabernacle(s) for Mast

GregSeaHawk
Administrator
Hi Joop,

I am not an expert, but my belief is that the base of the mast is largely under compression. However, there will be a constant sideways loading because of the pressure of the wind. Some of that is taken by the shrouds, of course.

As you know my experience with a tabernacle is reported at:
https://www.seahawk17.org.uk/owners-custom-sailing-tabernacle.php
You can see the original mounting plate for the mast in the third photo down the page at:
https://www.seahawk17.org.uk/boat-description-rigging.php

My recollection is that the original plate had only three bolts in it that were slightly thinner than those shown on the tabernacle page.
Greg Chapman
GregAfloat - My Boating Biography
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Re: Tabernacle(s) for Mast

Perry
Be aware also that as you put the mast up and down it has zero compression loading and quite a lot of sideways loading... and a tabernacle increases that in order to ease lifting and dropping.

My base (not tabernacle) has 4 bolts and I wouldn’t want to reduce that, especially if adding tabernacle cheeks.

Thanks

Perry
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Re: Tabernacle(s) for Mast

GregSeaHawk
Administrator
Perry's right!

Re-reading my post, it might look as if I was suggesting the extra bolt was unnecessary, but if you can justify fitting a tabernacle then you can expect to be using it and that means a lot more "unusual"  pressures not experienced by a mast that stands upright throughout the sailing season.
Greg Chapman
GregAfloat - My Boating Biography
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Re: Tabernacle(s) for Mast

ReneDirks
In reply to this post by Freedom
Hi Joop,
If you're ever in the area feel free to drop by and look/check/measure how it's constructed on our Seahawk.
Cheers
Rene
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Re: Tabernacle(s) for Mast

Freedom
Dear all, Thank you for your responses.
you made it clear and I will use 4 larger bolts then the three bolts there are now.
@Rene; it would be great to see how the problem is fixed on your boat. If it is not bothering you too much: Is there a possibility I can visit you and your boat the coming period?
kind regards,