what does a stuns'l boom do?

[Ian B]

I think I have the right name , it is the parallel booms on the upper side of  yard arms. Is this a feature all large square riggers have? It is not shown on my Billings Bounty model but a few Bounty builds and a lot of similar models have them? I am about to tackle making the yards and if they are needed then I need to plan out how I will do it.

 

Thanks

[JerseyCity Frankie]

Hi Ian. Stunsails (spelled Studdingsails) are supplementary sails that can be set on either side of the square sails. The booms you mention could be slid outboard through iron rings attached to the yards well past the ends of the yardams. On these extensions smaller square sails could then be spread, giving the effect of more canvas on each yard.  Here is an excellent recently posted photo of them in use on the the Europa which makes their disposition plain. Studdingsails were only set in light airs with the wind abaft the beam.

Most of the time the booms were not in use and they were positioned inboard, which is how they are usually depicted on models. The canvas on them was "flown" up to them from the deck, not furled on them at all when not in use. The sails could be set as needed and not necessarily all at the same time nor even symmetrically- you could set the portside ones but not the starboard ones, or even set the ones to port on some yards and ones to starboard on others. All depending on the wind. 

[Ian B]

That's great, thanks for the very prompt reply and explanation. Right now to look at some of the builds on here about scratch building them..

[JerseyCity Frankie]

They are regarded as difficult creatures. Studdingsail booms are almost thought of as disposable since they often break, as I have heard crew from Pride of Baltimore II report. They can only exist in light wind conditions and if the wind picks up they must be got in quickly. "Modern" square rigged ships seldom carried them, for instance none of the big steel hulled German barques had them.

[michaelpsutton2]

What a great pic!

[Stockholm tar]

Michael,

 

I agree, a very nice shot of the Europa which, since she looks to be in mid-ocean, was probably taken from her boat. I believe she is one of the few square riggers today that sets stunsails, on her round the world voyages.

 

In addition to what has already been said stunsails, like spinnakers on modern yachts, can be tricky to handle. Some years ago, 1991 I seem to remember, I sailed on what was then thought to be the oldest square rigger in the world, the brig Maria Assumpta (which, very sadly, some years later grounded and sank). She had stunsails, and it took some practice to get them set just right.

 

There has actually been some debate as to whether stunsails made any real difference to a ship's speed, and whether the effort spent in setting them really justified the advantages, if any, that were gained. I think the jury is still out on that one.

 

As the above pic show though, they do look good.

Edited August 13, 2014 by Stockholm tar

[geoff]

Hey Up  Ian, A little while ago I posted an idea for making footrope stirrups. Someone whose name escapes me (sorrywell I am 71 y'know!) sent me an article by Chuck Passaro which may be of use. He mentions stuns'l booms, yards etc.. It's called " Intermediate techniques for modelling yard details , Stuns'l Boom Irons,footropes,yard cleats,blocks,and more.".........Phew.! If you can locate & download it, it may be of use.  All the best, Geoff

Edited August 13, 2014 by geoff

[Kevin]

i posted the above picture in my thread a little while ago as i will be setting up all the studding sails in a diorama setting, here is another drawing 

 

[geoff]

A bit more info. Ian. The article by Chuck that I referred to can be found on the NRG website . It was sent to me by David Spindle.   Geoff

[ianmajor]

Direct link to that article is http://modelshipworldforum.com/resources/Mats_and_Yards/Making%20yard%20details.pdf . The file name has the simplified title of "Making Yard Details".

 

To find your way via menus, click on "The Nautical Research Guild Home Page" on the MSW banner at the top of this page, click on "Ship Modeling Resources", then click on "Ship Database of articles". This article is in the "Masts and Yards" section. It is a few more steps post NRG but all the old familiar stuff is in there.

[Ian B]

wow loads of super info, I am really glad I asked. thanks for the link. Next week I hope to sneak away from doing DIY and household chores when I am home and start creating them. Thanks again everyone.

 

Ian

[dafi]

I vaguely remember some scenes in MaC where the booms where used also for the handling of the boats, when "parked" beside the ship. Was this a common use? Like the main one on Victory that is in a almost ready to use position?

The other question concerns the downward lanyard. Where and how was this one fastened? Hooked into a bolt beside a gunport? Some sheeve going into the hull?

 

 

XXXDAn

Edited August 14, 2014 by dafi

[ianmajor]

I, like Daniel, am unclear about how these were fastened. I have looked at my Lees and Petersson and they don't make it obvious to me.

 

I would like to add a question to this. Lees refers to "Lower stunsail booms", "Upper stunsail booms" and "Stunsail yards".

 

Now I can see how the lower booms are used, for example hinged on the main channels, but I struggle to see where the upper booms versus the stunsail yards were used. Any thoughts on the above 2 questions?

 

(BTW Dafi, I see that you have 1000+ posts and it is Captain Dafi now! )

Edited August 14, 2014 by ianmajor

[robnbill]

These were unlashed from the inner booms where they were stored. Then they were pushed outward. They were supported by halyards from above. So they probably only had the foot of the boom end still  in the ring on the end of the boom. Since these were used in light airs, that is all they needed. 

[CaptainSteve]

Awesome painting, Crackers !!!

 

And thanks especially to Ian and Dafi et al for this invaluable information. 

Edited August 14, 2014 by CaptainSteve

[Stockholm tar]

Ian,

 

As you say the lower stunsail booms were hinged to the channels, and were swung forward in use. I believe the 'upper stunsail booms' were those pushed outward from the yards, and the 'stunsail yards' were the short spars attached to the head of the stunsails themselves and hoisted, with the sail, up to the stunsail yards. I stand to be corrected of course.

 

Dafi,

 

I think you're right. The lower booms were swung out and used for mooring the boats when in harbour.

[dafi]

Ian,

 

As you say the lower stunsail booms were hinged to the channels, and were swung forward in use. I believe the 'upper stunsail booms' were those pushed outward from the yards, and the 'stunsail yards' were the short spars attached to the head of the stunsails themselves and hoisted, with the sail, up to the stunsail yards. I stand to be corrected of course. 

 

That too is my understanding. As far as my knowlegde is, that with the Victory, the main stunsail booms were hinged to the main channels and the fore ones were stowed in the waist with the other spars. Possibly for not obstructing anchor work. The USS Constellation possibly had another arrangement.

 

xxxCAPTAINdafi

 

Thanks Ian!!!

Edited August 14, 2014 by dafi

[ianmajor]

Captain Dafi (or should that be Sir now!),

 

An interesting point you make about the fore lower studding boom. It did occur to me that there could be a conflict twixt boom and anchor if the boom was attached to the fore channel. The main lower boom irons on the main channel are nicely illustrated in Dan Vadas' Vulture log at http://modelshipworld.com/index.php/topic/230-hms-vulture-by-dan-vadas-1776-148-scale-16-gun-swan-class-sloop-from-tffm-plans/?p=159222

 

The only info on the fore lower booms attachment that I have seen is in Petersson page 110.

 

 

The boom is hooked in to an eye in the hull rather than on the fore channel. This mounting point is well forward of the foremast so I guess when deployed the boom would point rearwards at about 30 degrees to avoid pulling the sail forward.

 

None of this answers your question on the downward lanyard.

 

 

[dafi]

 

All the lifts and guys are mentioned somewhere but the martingale ...

 

McKay shows the following:

 

Fore boom on an eye bolt in the middle in between cathead and fore channel and a bit higher than the channel. 

All lifts and guys are in fixed in the middle of the boom with loops held by a clamp.

Underneath the hook on the hull there was a down holder to prevent unhooking (McGowan page 190)

 

The topping lift:

In AOTS it goes to a block underneath the fighting top and then possibly to the fore bits (front or aft the mast?). Circumference is 3,5"

In McGowan the block is on a long pendant from the lower mast cap and possibly going to the timber heads of the fore castle.

 

In AOTS the after guy comes from the aft fore channel deadeye and goes to the middle of the boom and the front guy goes from there to a block on the outer edge of the spritsail yard back to the timberhead beakhead bulkhead (?). Circumference 3"

in McGowan not really to be seen.

 

The martingale is the downward counter part of the topping lift.

In AOTS it goes down to the level of the upper edge of the whales, means lower edge of the gunports. Also 3,5" suggested?

In McGowan page 190 it shows an eyebolt and a hook. Height is difficult to recognize.

Petterson shows the main boom martingale with a block on the height of the whales, free end pointing direction of the channels

 

XXXDAn

 

PS: Ian, Sir will do it ;-)

Edited August 14, 2014 by dafi

[mtaylor]

To briefly corroborate what Kester said.. here's that picture and I've highlighted the stunsail yard.

 

[dafi]

Here Sir dafi again :-)

 

Lee mentions plenty details pages 115-119 but does not mention the martingales ...

(... or I did not get it as it is in english ...)

 

Nares shows the setting from page 106 on and plates 159 and 160.

 

Lever shows it on pages 81 and 82. The martingale has a block and is led up to the fore castle - but this is a version 50 years after my time slot :-)

 

XXXDAn

Edited August 15, 2014 by dafi

[Kevin]

every time i look into this subject i find more info, i had not even thought about where  the fwd stuns are attached when deployed and for some reason i thought the stun boom would support the top of the lower sail and the bottom of the one above it, 

[Stockholm tar]

every time i look into this subject i find more info, i had not even thought about where  the fwd stuns are attached when deployed and for some reason i thought the stun boom would support the top of the lower sail and the bottom of the one above it, 

Kevin,

 

And not only this subject... The stun boom itself would also have to be supported, and so on, and so fifth... (as someone, who's name I can't remember, once said.)

 

Ian,

 

Yes, that's just what I meant.

[popeye2sea]

Stockholm, it was Victor Borge in his skit where he adds one to every number in a story. 

Edited August 19, 2014 by popeye2sea