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Alex Rhineladner
12-16-2005, 11:47 AM
I've been thinking about upgrading Comet II's boom gallows for a while, but it hasn't been a priority until now: in order to get the boat into her new berth in the shed at the LaHave River Yacht Club this fall we had to remove the old one. It was a bear to get off, and was damaged in the process. So, since the new gallows will have to come on and off annually, it's now time for the upgrade.

Many of Comet's sister schooners in the NSSA fleet have gallows of a similar design, and I'm leaning toward it. It consists of a bronze upright which has been welded to a bronze bar that is bent to accomodate a wooden crosspiece. The uprights are then set into a bronze socket which is screwed onto the deck. A good example of this design is on Tom Gallant's schooner AVENGER (see photo below).
http://www.amschooner.org/files/gallows_Avenger01.jpg

I realize that there is a similar commercial product available (see www.sailorsams.com/mall/boom_gallows.asp (http://www.sailorsams.com/mall/boom_gallows.asp)
), but the lines of these home-grown versions seem more in keeping with the workboat heritage of our schooners (and I'm hoping to save some $$$).

Another interesting option is to recreate a gallows that I spotted in a shed at the Maine Maritime Museum in Bath (photos below). This looks like it might be easier and cheaper to do.

http://www.amschooner.org/files/gallows_mmm01.jpg http://www.amschooner.org/files/gallows_mmm02.jpg

I would welcome any thoughts you might have. Particular questions that I would ask are:

</font> Which version do you prefer (or do you like the original oak below)? </font> Where might I go (in the New England / Nova Scotia area) to have the necessary bronze welding done? </font>http://www.amschooner.org/files/gallows_CometII01.jpg
Thanks,
Alex

Alex Rhinelander Schooner COMET II (http://www.amschooner.org/?q=node/11)

MAGIC's Craig
12-16-2005, 01:06 PM
Hi, Alex:

We chose this style for our schooner, MAGIC, and Bent Jespersen carved out the patterns for the casting of the bronze top pieces. Local Pacific NW foundries seem to have a couple of similar ones in inventory. http://www.imagestation.com/picture/sraid40/pe5fe48bc3c96fc1d242b87dde42e7383/fcffadd1.jpg

One of the reasons we chose a more rounded shape was to minimize entanglements with the mainsheet when gybing. http://www.imagestation.com/picture/sraid40/p8ad227661da0eb5040b9bf1ba3e5552d/fcffadd6.jpg It does seem to help on those days when Murphy has not planned something else to "entertain" us.

Fun project!

Cheers,

Craig and Vicky Johnsen

bgarvey
12-16-2005, 02:17 PM
Hey Alex -

Just got your oher email - will reply in more detail to that one.

I like the curve of craig's one above - I think it would suit Comet nicely. As for the bronze work, there are a few options -

there are some nice curved gallows socket fittings like the ones on Magic above on the market. I haven't looked recently but I've seen them before. Newfound metals rings a bell with me somehow, and I think even ABI has something that they import.

As I mentioned in another thread (and as you've seen I think) I have this wacko new prototyper here that can output any damn design you like - we just have to model it and print it. The printed forms are easily tough enough for traditional sand casting, and if you want higher detail, we can do it in a starch that could then be investment cast using a ceramic slurry and a burn out method. I've been playing with the folks at NSCAD foundry, which has been fun, but it's not very reliable. There is a caster in Amherst N.S. called Liberty Enterprises, who does nice stuff in aluminum and bronze. i'll probably bring my final patterns to him for casting ultimately. Maybe you could check in with him (I believe his name is John Kelligrew). I know he does stuff for Stright mackay and others (trap haulers and the like).

It's an opportunity to include other things too - like how do you terminate lifelines back there - would an eye or reinforcement bracket on the vertical help in that regard? or the hanger for the lifering, stern light, etc... I'm facing the same job on my boat too, and I plan on trying to make some custom castings... just because I can!

I've had some excellent bronze welding done here - there are several fabricators that have the correct rods and gear, and experience to do it (hangovers from the naval dockyard work where the heat exchangers on the subs are all bronze and various other cupro-nickel allows that have specific welding procedures). So fabricating from bar and rod isn't a problem either. In fact I have about 60' of cast al-bronze flat and round bar sitting on the floor in the basement here, waiting for a spare moment to be turned into lifeline stancions and a boomkin. As you now know - the kids tend to overshadow old plans!!

We'll talk more over xmas-
ben

Don Kurylko
12-16-2005, 11:17 PM
Wow, what a co-incidence! I’m just at the stage where I’m deciding whether to make up a pattern for boom gallows for my 34’ gaff cutter. If there are any others, maybe we could pool our resources and come up with something that could meet all our needs and save a few bucks in the process.

I can contribute by offering to draw up the prototype in my CADD program so that we can have accurate full size plans to work from. My wife’s cousins in Vancouver also own an aluminum and bronze foundry that could do the castings for a reasonable price. They have been in business for over 50 years and have catered to the commercial marine trade predominantly.

Or maybe we could “rent” the patterns for Craig’s Magic and have a bunch cast up. Anyone interested in pursuing this further?

Cheers,
Don

mmd
12-17-2005, 01:12 AM
So you're the fellow who bought Les Caslake's boat! I have known Comet II for quite a few years, and visited with David Stevens when she was under construction.

I spoke with Pete Tanner of Stand Fast Fittings in Blue Rocks earlier today - he has just finished doing some bronze fabrications for Covey Island Boatworks. If you are considering a fabricated piece rather than a casting, he has some material available. Please note that quality structural marine-grade bronze is hard to come by and expensive; Pete had to have the required 1/4" plate imported from the USA at a scandalous cost. He suggested (somewhat tongue-in-cheek, I think) that if you want a strong boom crutch that is both relatively inexpensive and salty, make it out of stainless steel and coach-whip the uprights.

Don Kurylko
12-17-2005, 03:36 PM
mmd, it’s pretty common over here to use schedule 40, 1 ½” nominal, red brass pipe for the gallows posts. Galvanized pipe would be a cheap alternative too, with the suggested coach-whipping to hide it of course.

Alex Rhineladner
12-19-2005, 09:54 AM
Craig- Thanks for the feedback. Your gallows look great, and I'll give the rounded style some thought. Fouling during a gybe isn't something I've ever had a problem with, though. Maybe the way the sheets are led...

Ben- Lots of good ideas. I'll catch up with you next week and we can chat it over.

Don- That sounds like a good idea. I'm heading up to NS over Christmas, though, and don't want to commit to anything until I've had a chance to talk to folks up there. I'll check back in in January.

MMD- I, too, was lucky enough to see Comet II in David's barn -- one of the things that makes owning and sailing her even more special. Drop me a line privately if you want to chat more.

Don- I've heard of using sched 40 pipe for uprights as well (it's even suggested on the page selling the commercial versions of the rounded brackets -- see http://www.sailorsams.com/mall/boom_gallows.asp).
Sounds like a reasonable way to save some cash -- does anyone out there have a reason not to use it?

Alex

[ 12-19-2005, 10:07 AM: Message edited by: Alex Rhineladner ]

Alex Rhineladner
01-04-2006, 05:56 PM
Here's an update on my boom gallows thoughts:

I still like the look and feel of AVENGER's bronze gallows, but am leaning towards replicating them in galvinized steel. Here are two photos of DOROTHY LOUISE, another David Stevens schooner that has similar ones:

http://www.amschooner.org/files/DL_Gallows_01.jpg http://www.amschooner.org/files/DL_Gallows_02.jpg

I'm thinking that I could have galvanized copies of AVENGER's made, then hot-dip the result and cover almost all of it with coach-whipping to look like Tom's (top).

Any feedback, Y'all?

________________
Alex Rhinelander
Schooner COMET II

gaffman
01-05-2006, 11:24 AM
May I interject with a boom gallows question? I have a gaff main and use a pair of topping lifts but should employ a boom gallows.
The boom is 35' long and carries about 650' of sail. I mention this to point out that when the main and boom come across, it is with some respectable momentum.
The problem I've always considered, and the reason I haven't made a gallows yet, is that when the boat is nosing into sloppy water with little wind, the boom will not only fly wildly
3-4 feet from side to side, but will also heave up and down a foot or so with the movement of the boat and lack of sufficient wind. Again, this is with the main hoisted and heading into 5 foot seas without enough wind. When this happens, the boom has "subdural hematoma" written all over it because it swings sideways and heaves up and down. My concern is that it will flail up and down and smash into the gallows. I've considered telescoping legs on the gallows so they could be dropped 2 feet. Any suggestions?

Andrew Craig-Bennett
01-05-2006, 11:44 AM
I'm planning to replace Mirelle's gallows. I've got four points:

1. A question for Craig - do you find the single position gallows restrictive, vis a vis the three position type? I ask because I would like to make the new gallows a little narrower, so that only a single position would be feasible, in order to improve access along the deck.

2. A reason not to use galvanised iron for the gallows uprights is that vertical iron has a marked effect on the compass. 316 stainless is OK I believe, as of course is bronze.

3. Gaffman - I do wonder if you might be happier, as I certainly am, with a mainsail cut so that the boom steeves up noticeably from gooseneck to clew? This pattern has two advantages - first, the boom is less inclined to drag in the sea when running hand and rolling, second, it gives ample clearance over the afterdeck and cockpit!

4. Last point - Classic Marine have patterns for the curved corners but would like another order or two besides mine before casting some...anyone interested? They have two sizes as I recall.

[ 01-05-2006, 12:58 PM: Message edited by: Andrew Craig-Bennett ]

MAGIC's Craig
01-05-2006, 01:23 PM
Hello, Andrew:

In our experience, a single position notch has worked well. When it is time to snug the boom down, it does not seem to make any difference whether there is only one notch or three.

One argument for three (or at least two) notches is if there is not sufficient headroom under the stowed boom for the helmsman/crew to stand without bonking their heads, then it is nice to be able to cinch it down off-center. In MAGIC's case, I planned for enough headroom, so a single notch suffices.

When our main is stowed and the trysail set, the sheet comfortably clears the bunt of the furled main when it is in that centerline notch.

gaffman
01-05-2006, 01:48 PM
Andrew, thanks for the thought. I'll have to think about that. I have had the occasional boom drag in a rolling run. Any guess as to what boom angle would cure that issue?

Alex Rhineladner
01-05-2006, 09:17 PM
Gaffman: I've sailed on many a gaff boat with boom gallows, on none of which has the boom ever hit the gallows while under sail. The height of your gallows should be set so that the last bit of sail hoist raises the boom above the level of the gallows. The boom is clear to swing back and forth above the gallows without contact, but needs to be guided into a slot (I prefer to have three available) as the sail is lowered. One extra point: if you look closely at Avenger's setup (top photo) you can see a hinged prop in the center position. This neat feature lets you raise the boom further out of the way when you're setting up for social time in port.

A question: Comet II's binnacle is about 8' from her gallows. Is there likely to be a problem with two 4' galvanized uprights and the compass at that range?

Alex

Andrew Craig-Bennett
01-06-2006, 06:19 AM
Craig - thank you very much. I could manage one boom position, or two, but not three, because I want to mount the gallows on the quarter posts, so as to clear up the deck a bit. This reduces the width of the gallows so one could get past them, outboard. I reckon two positions might be seamanlike, but would look ungainly, so your advice has convinced me to go for one only. I like the idea of being able to raise the boom a little higher in port but it is not very much in the way as it is.

The gallows is original but I don't think it is man enough for the job. I've broken and repaired it once already.

gaffman -

http://www.woodenboatrescue.org/image.php?Id=502

If you look at old photos, almost all working boats have it, whilst yachts do not - the yachts raced in smooth water and needed all the canvas they could wear, whilst the working boats sacrificed some mainsail area for a quieter life in a seaway and less risk to the crew in a gybe.

As you can see, the boom is well clear of the heads of folks standing in the cockpit.

gaffman
01-06-2006, 10:11 AM
Andrew, I may just visit the sailmaker with this thought. It would solve a multitude of problems although I do prefer the look of the boom parralel to the deck/house. Your thoughts are appreciated.

Andrew Craig-Bennett
01-06-2006, 10:47 AM
Alex asks:


A question: Comet II's binnacle is about 8' from her gallows. Is there likely to be a problem with two 4' galvanized uprights and the compass at that range? I am not a compass adjuster!

But, with that very important proviso, I seem to recall that iron is more likely to affect the compass if it is within six feet of it.

David W Pratt
01-07-2006, 05:20 PM
Truth's gallows acts as a roll bar, it is above head height so boom can't go boom on heads.
One suggestion, put three notches in so boom can be stowed on side opposite boarding side.
Good luck.