Disregard that forward hatch statment-upon further review I've found the errors of my ways
Disregard that forward hatch statment-upon further review I've found the errors of my ways
Thanks Scott!
AWESOME SITE!!!
Cheers, B.
Commander #215
Tony,
I added to the site after completing my rehabilitation project. The site remains a work in progress. As I said earlier, loading time is a problem.
The Garhauer lifting davit is a one-person operation. The tabernacle is likewise. Last fall, I sailed single handed about 60 percent of the time, and often returned to the harbor after dark.
Since I must pass beneath a bridge with a height of around 21 feet, I must lower the mast each time I pass under the bridge in either direction, so that means rigging the boom guys, and releasing the aft lower shrouds and backstay twice on each sail. On the way out I do that at the dock, and then I reattach the backstay, remove the boom guys and reattach the aft lower shrouds as the boat, assisted by a knotted bungee cord strapped to the tiller, motors out of the harbor channel amid cross traffic, while I deal with the rigging.
On the way into the harbor, I have to drop and secure the sails, and then once again install the boom guys, detach the aft lower shrouds, and remove the backstay.
I have not photographed the boom guys, but I added two adaptations to the customary tabernacle running rigging design. Firstly, my permanently installed lifelines are set up so that the lower lifeline runs from a pad eye at the forward edge of the boarding step to the pivot point on the upper shroud, thereby eliminating the need for a separate bridle to stabilize that pivot point. Secondly I made my boom guy up of a single length of line, and left a loop in the center, such that clips on the each end attach to the upper shroud pivot point, and two additional clips attach to a strap on the aft end of the boom. The aforementioned runs loop is between the two clips that are attached to the aft end of the boom. The loop hangs down from the boom, and a clip at the center of that loop secures to a pad eye in the center of the bulkhead at the aft end of the cockpit right where the manufacturer's nameplate and boat number were originally installed. This loop is essentially a fixed-length second mainsheet. It serves as added insurance that my mast is not going to fall forward if someone inadvertently releases the main before I am ready to lower the mast. I release the clip at the center of that loop just before I lower the mast.
So in any case, with a new Garhauer mainsheet 4:1 block set-up (the light blocks with the ball bearings) and a bad back, I can easily drop and raise the mast in a tabernacle single hand when under power. I originally bought a dual action 4:1 / 8:1 block. That made lifting the mast even easier, and I may use it from time to time. But you only really need the 8:1 ratio for the first ten vertical feet as the mast is raised, and you have one heck of a lot of line on the deck when you are done. That is not a fatal flaw, but that dual action block also spills a lot of line in the cockpit during a jibe. Also it is very much easier to control one line in lowering the mast as that one line runs between your fingers, than it is to control two such lines, particularly after dark when the lines are wet with dew. So after using the 4:1 / 8:1 mainsheet for a month, I switched to a straight 4:1.
One last thing should be mentioned. If you intend to use your tabernacle system to step the mast, or work on the mast head, be sure to raise your mast pivot point high enough off the deck so that the mast will clear the forward hatch as it approaches the horizontal. My mast is mounted to a thin stainless steel mast step, and the pivot point is very close to the deck. I am able to reach the masthead main sheave from a stepladder if I first remove the forward hatch cover and then lower the mast, but it would be very difficult to unstep the mast even then, because the masthead is still about ten feet above the dock. Nonetheless by removing my hatch cover I was able to lower my mast far enough to free up my frozen masthead mainsheet sheave, and replace my wind vane. Still, it is a bit precarious standing on the top step on a five-foot stepladder on a sometimes less-than-stable dock.
Regarding that painted mast, my mast paint job is not all that sweet a situation. A prior owner painted the mast with a corrosion-proof paint that proved to react poorly under UV Light. The paint is decaying into an irritating fine powder that stains the sail cover. As a result I have not replaced the rather worn sail cover. Unfortunately I will have to take the mast down to bare metal before repainting. The upper part of the mast is practically there already…Oh well, maybe this summer, and then again maybe next summer, or…
The photo attached slows the section of the lifeline that functions as a bridle for the tabernacle.
Scott
This photo shows the mast base including the stainless steel piece that I added to facilitate running the lines back to the cockpit. Note the height of the mast pivot point. This is too close to the deck if you are going to lower the mast all the way to the bow pulpit (because the forward hatch cover will be in the way), but then again, maybe you don't want to do that anyway.
If you do raise the mast base pivot point, you will also have to raise the upper shroud pivot point to the same elevation above sea level.
Scott
I'd move to another marina on the otherside of the bridge !
Tony,
And by the way, yes I did modify my backstay to break it at the approximate height of the boom so that I could attach a pelican hook to a bail at the end of the boom. That placed the tensioning device at chest level, which I like because it can be a real pain to have to reach over the raised motor hatch to tension the backstay under power. However, I had to devise a special wrench to be able to tension the backstay without unwinding the lower section of the wire. The wrench was made from hardware store parts and cost me less than ten dollars in total.
You can see the bottom part of the tensioning device and my Garhauer4:1 / 8:1 dual-action mainsheet block in this photo. A pelican hook attached the top portion of the backstay to this tensioning device.
Scott
Scott, Thinking of you , underway, in traffic, slipping under a bridge, alone, raising your
lowered rig, securing it and hoisting sail intrests me. That you do it twice every time you
go sailing blows my mind.
I really never considered lowering the mast forward. Cool. Now I'm trying to get the idea.
You use the boom as a gin-pole. There are guys that are attached to the boom, or the aft
lowers? I think you said the aft-lowers. What do you use to connect/disconnect the backstay
and lowers. How do you re-tension the rig? When the boom gets nearer the perpendicular
does it need a pair of guys as well. Do you use a crutch of any kind to take the load off the tabernacle?
I would like to hear more about this process. I was thinking about shipping the mast basically for the winter.
To be able to raise and lower on a whim opens up new waterways and eliminates climbing the mast
and paying someone to take it down. To do so is to make the boats rig eminently more managable,
and the economics more reasonable. Now, the tabernacle hardware did you make it yourself ? It looks
alot more thought out than store-bought. If so would you mind shareing your specs? Did you
modify the mast foot?
Dude, we gotta talk!
In the Meantime,
Hearty Cheers, B.
Commander #215
Brendan,
The local tabernacle rig as commonly executed here consists of the following elements:
1. Your mast step is modified by replacing a fixed mast step, with a stainless steel plate with a riser on each side of the mast. This riser is also stainless steel, and may either be welded onto the flat plate, or may be integral to the plate, in which case, the plate is bent upwards on both the port and starboard side of the mast to form the riser. A hole is drilled through these two risers, and a matching hole through the mast. Generally, a wooden plug is inserted in the mast base, and the front edge of this plug and the front edge of the mast base are beveled to permit the mast to rotate forward. Finally a stainless steel bolt is inserted through the matching holes in the mast and risers. A nut secures this bolt.
On my boat, Ariel #330, "Augustine", the previous owners made this modification, by having the mast base plate and risers made up by a local vendor. An additional flange was added, which curved upwards at a forty-five degree angle from the base past the risers. On each side of the mast, his flange was drilled with four holes to permit the attachment of blocks.
Unfortunately this flange is so low that any lines run back to the cockpit from blocks shackled to the flange run foul by abrading against the top lip of the raised portion of the trunk cabin. To prevent abrasion, I designed the extension plates shown in the photo above to which the mast base turning blocks are shackled.
2. The backstay is broken at either the deck or at the height of the boom by use of a quick release pin or a pelican hook. Use of a pelican hook is preferred because a pelican is stronger and safer in my opinion than a quick release pin. My last boat used a quick release pin. Quick release pins are quick but they don't give me a great sense of confidence.
3. Both aft lower shrouds are broken, usually above the turnbuckle, and reattached with pelican hooks. Don't use those pelican hooks designed for lifelines. Simple strong pelican hooks can be cut from stainless steel, and can be manufactured easily by any machine shop stocking the grade and weight of steel that you want to use. It is not practical to slacken and tighten the aft lower shroud turnbuckles each time you use the tabernacle rig, so you will have to sail with aft lowers that are loose enough to detach and reattach without loosening the turnbuckle. The good news is that by cranking down on the mainsheet you will see that you can effectively slacken the aft lower shrouds a bit. A well-designed pelican hook will serve as a lever so that while you lifting on that lever to close the hook, you will be able to easily reattach the aft lower shroud, even is it is a bit tight.
4. An attachment device, shackle, ring, etc is attached to the upper shroud at a height above the waterline equal to the height above water line of the bolt running through the base of the mast. Therefore the mast base pivot point is in a straight horizontal line with the two upper shroud pivot points. By the way, the shroud pivot points must be at a place that actually does bend without stressing the rig components, like a T bolt with toggle at the top end of your shroud turnbuckle.
That is all of the required hardware for the standing rig modifications. Now for the running rig:
The running rig consists of two components.
1. A set of boom guys. Most people use two lines with a carabineer on each end or a less or more expensive clip of some sort. Each line is attached on one end to the aft end of the boom and on the other end to the upper shroud pivot point. The purpose of these two boom guys is to prevent the boom from flopping to one side or the other as the mast is lowered. This is very important and critical, since bad things can happen to hardware and people if the boom flops to the side. At the boom end of the boom guys, the carabineers or clips on the boom guys are attached to a bail or some other attachment point on the boom. On my boat I used a bail.
I used a single line with a loop in the center as described in my earlier post. This line secures the two upper shroud pivot points to a bail on the aft end of the boom. The loop falls down and attaches by a free running clip onto a pad eye on the bulkhead at the aft end of the cockpit to prevent accidental lowering of the mast once the backstay is released. In total, I used oversized bronze clips from West Marine at about $3.00 a piece (fixed eye boat snaps on West Marine 2002 catalog page 981).
2. A set of two bridles. These two bridles connect the upper shroud pivot points to a point on the deck aft of the upper shroud. These bridles are often fixed bridles made of stainless steel wire that run from the upper shroud pivot point to the base of the aft lower shroud. In my case, I had no lifelines and no stanchions. I was unwilling to drill holes in my deck, given the nature of the deck structure near the toe rail, and my observation of cracking in the area of stanchions on other Ariels. I also do not believe that traditional stanchion secured lifelines are as safe as they appear to be. Certainly they are safer than no lifelines, but I decided to design a new system based on an idea presented in Dan Spurr's Boat Book. You will find that sketch of Frank Mulville's cruising lifelines on page 171 of the second edition of "Spurr's Boatbook Upgrading the Cruising Sailboat". This was the inspiration for my adaptation. See my web page at: http://www.solopublications.com/sailarip.htm for photos of my adaptation of the same theory for installing double lifelines on an Ariel.
In my system, a lower lifeline running from the upper shroud pivot point to a pad eye at the forward edge of the boarding step in the photo above doubles as a bridle. It is permanent and fixed. My lifelines could be either wire or Dacron. They are at present three strand Dacron. My lifelines are designed to be secure places to attach harness safety lines, since they run to through-deck pad eyes on either end.
The purpose of the bridles is to stabilize the upper shroud pivot point so that it does not move forward as the mast is lowered. In other words, the upper shroud pivot points and mast base pivot points remain in a straight line during the tabernacle operation.
No crutch is necessary as would be the case if you were to instead lower your mast toward the stern after removing the boom, as is the procedure on some trailer sailors.
On the mast tabernacle installed on my boat, the mast is stabilized by the boom guys, bridles, the upper part of the backstay, which is attached by a pelican hook to the bail at the aft end of the mast to which the boom guys are also attached, and very importantly by the tightened boom vang.
If you made a drawing of this tabernacle rig, you would see that the set-up is structurally sound, being composed of a whole mess of very stable triangles. Even better, look it up in Bruce Bingham's "The Sailor's Sketchbook" page 32-36. Bruce Bingham talks you through you through a series of thirteen detailed sketches of a well-designed tabernacle rig. The drawings show details of all of the components, and demonstrate the operation of the rig in progress. Everyone ought to own at least one copy of "The Sailor's Sketchbook" in my opinion anyway. The book is a lot of fun, and will inspire you to many projects from anchor brackets to wooden ceilings. Sorry, but I couldn't find any projects in the book starting with the letter y or the letter z.
Scott
I am not aware of any store-bought options for tabernacle rigs. In 1984, on my first boat, a Catalina 22, I adapted a mast base plate that I found in a marine yard to tabernacle my first boat, and borrowed swaging tools to adjust my wire to accommodate a tabernacle. A rigger made up the pelican hooks, and installed the equipment for me. I did not install bridles, but the rig on that boat worked satisfactorily anyway.
I was fortunate that my Ariel was tabernacled when I bought it. The existing set-up was a two-person operation, which in my opinion was neither safe, nor practical for single-handing for a number of reasons. Nonetheless, I did have the mast base plate and the pelican hooks. I had a rigger modify my backstay, so that it would a break at boom height. I added boom guys, my lifeline/bridle, some clips (West Marine fixed eye boat snaps catalog page 981). The bail on the aft end of my boom on which I attach the boom guys and backstay during the tabernacle operation is new also.
My backstay-tensioning device is similar to the "backstay turnbuckle jaw and jaw" in the West Marine catalog page 354. I made up the tensioning wrench that I use with this device. However, to date, I have found that I can maintain the proper tension on my backstay by cranking down on the main sheet before releasing the backstay, and similarly cranking down on the mainsheet before reattaching it. Therefore, tensioning the backstay before and after each sail is unnecessary. All of the shackles that I needed were available at West Marine. Actually I use a ring and shackle on the aft lower shroud pelican hooks. The ring slips over the closed pelican hook. This slips quickly over the hook. Once the shroud tension has been reestablished, a pin is inserted through the shackle (key pin locking halyard shackle West Marine 2002 Catalog page 982), and a hole in the end of the pelican hook to insure added security. A variety of rings are also available at West Marine. I don't have specifications on my pelican hooks, but I would be glad to trace one for you and mail it to you if you e-mail me your address. As for the mast base, don't use mine. If you do, the pivot point on the mast will be so low that you will not be able to lower your mast all the way to the bow pulpit without hitting the forward hatch. So, design your own and have one made up for your boat. You will get some ideas for this plate from looking at Bruce Bingham's "The Sailor's Sketchbook" referenced below.
And yes, you should be able to do one heck of a lot of mast work right at the dock, no fees, and no mast climbing. If the mast is lowered and then braced on the dock end, you could easily remove the mast.
One additional comment should be made. Do not allow anyone out of the cockpit during tabernacle operation. If the mast drops forward do to operator error or component failure, a person forward of the mast could be injured.
Finally I love the upper harbor here. I have the benefit of a slip in n clean inland riparian environment and easy access to the open sea. Although I must lower and raise my mast to get under the bridge, I am able to do at of this and raise the sails alone while motoring in a more or less straight line out of the harbor. The only added time occurs results becausae my running speed is necessarily slower than it might be while I am on my way out of the harbor, since I need to be away from the tiller to install and/or remove the running portion of the tabernacle rig.
Scott
Hi Scott,
Thanks for the additional info on the Tabernacle rig. I'm going to
get one made this winter for use next season. Also, in the pictures ,
those blocks of yours look pretty sharp. I am assuming they are
Garhauer from your info. Where can I get info/catalog?
Also, I'm thinking I might try to incorporate the wooden mast step
and the tenons on the bottom of the mast. I like the rig set up
pretty tight and to do so, if the mast rests on a bolt alone, is to hasten the demise
of the tabernackle. The bolt could sleeved with steel that is softer
than the risers . The sleeve could be replaced easily and you would
save the holes in the riser from elongation resulting from the compressive load
on the rig in compression.
What I'm thinking is that if the pivot shaft was trapped in a "T"
shaped slot in the risers I could retain the idea of the shock absorbing
mast step and seat the mast into the step using the tenons to locate the mast
and take the compressive load.
I realize that the depth of the tenons will dictate the length, or really the height of the slot
and the amount the rig will need to be loosened in order to get the mast stepped/unstepped.
Any thoughts on that ?
I like the idea about plugging the mast's bottom to secure the pivot bolt .
Cheers, B.
Commander #215
Brendan,
The Garhauer website is found at: http://www.garhauermarine.com
The Garhauer phone number is (909) 985-9993. They offer some special deals at boat shows and do not sell through retail stores. They have a well illustrated catalog. The blocks in the photograph are Garhauer series 30 single blocks with swivel shackle (model 30-13SL)
The "SL" means that they are in the Garehuaer Stainless Steel lite block series. There is very little friction in these spiffy blocks. I bought them last year for the 2002 catalog price of $16.50 each + tax + shipping.
However, I specified a screw-in shackle pin instead of a slip-in pin with a retaining ring as pictured in the catalog. So get a Garhauer catalog and have some fun. These a bearing blocks, so it is best to wash them with fresh water after use in salt water. Garhauer also stocks the more traditional solid stainless steel blocks for a similar price.
Scott
And if you really want to impress your dock mates, go for the Garhauer titanium blocks!
There seems to be a kind of rake in the 'search' mode of this site that will find stuff no matter where it is. 'My Ariel Althea' on the Gallery channel has a thread on the above subject. And it has been discussed often elsewhere.
I didn't pay too much attention to the deck lam when the flange was cut away in a larger square for the new Bomar coach roof hatch. So I made the liner frame and glued up some curved backup pieces for something to bolt to, and noticed, finally, that something wasn't right with the balsa core on the maststep side of the cut out.
Well, repairs had been made to the 'under-the-maststep' area to various violations thru the deck for wires over the years and I thought it was done. But recently I was worried about the 'point load' of the mast on the cored deck. Pearson had no filler piece under the mast in the core, other than balsa.
Now, it was evident that the hatch hinge fastenings over time had let fresh water into the core. Black shrunken core. Poking into it discovered that the 'tunafish' colored stuff wasn't too solid either. So with the trusty 5 1/2" skillsaw cut a rectangle back almost to the doghouse in the top fiberglass layer - that incorporates the maststep area. About 10" X 20". Blackened balsa where the wire thruholes were. Chiseld and scraped the good and the bad wood out down to the rather thin and flexible inner fiberglass. Intend to layer in xmat to the surface. That ought to spread the load. Mast pad, deck, compression beam will all be solid and hopefully incompressible.
But I'm wondering about all those other deck fastenings now because they were merely plugged with epoxy goop when the boat was stripped!
Last edited by ebb; 07-22-2003 at 07:44 AM.
Ebb
Are you admitting that you didn't dig out around those holes before filling with epoxyI find that hard to believe. You know-the whole bent nail in the drill thing and all? But hey that solid mast step has gotta feel good. Because of the butcher-job done on 113 her mast step will have to be fixed from the outside also. 'Thinkin solid just like your's. so, how many layers does it take to build up 1/2"?
Capt. T,
5 layers of the heavy (25oz ?) xmat will get you 1/4". I will make sure as many as possible will get tucked under the edge of the excavation.
It was raining when the holes got plugged. It was a semi-temporary, didn't have the tent then, and there seemed to be holes everywhere. Got this readymade white stuff and pushed it in with the blade until it came out inside. Sometimes it was a little, sometimes a lot. When I get to prep the deck I'll open some up to see if it's a rot area. Don't have any squishy areas in the deck, yet it's likely that there is decomposed balsa at every fastening hole. And probably not in a symetrical donut shape!
Found black balsa at the thrudeck chainplates. [Also found that the tops of the chainplate knees inside had some rot.] There I filled the cavity on the deck, after the plates were removed, just enough to get a hard surface, then a hole saw was used to open each area up.
Used a sharpened allen wrench to excavate around the hole,
taped the bottom, filled wish mishmash, and pressed the holesawed lid back on top. Doesn't look pretty. But I think new slots for upgraded plates will work ok.
I worry that contaminated balsa is still inside there. I'm aware of no fix for rot except complete removal (penetrating epoxy notwithstanding.)
Probably will do exploratory holesaw excavation where the tracks were. The vent hole up front is another real suspicious area. Leading Mike, for one, to do a whole heroic recoreing of his deck!
Isolating fastenings with oversized epoxy plugs is absolutely necessary.
Keeps water out, fastens top to bottom of the composit, creates a non-compressable column. I think I remember some enterprising dude drilling thousands of holes in his deck, excavating them, and troweling on the miracle epoxy.
(I'm in total denial about the possibility of having to recore. I prefer to be completely surprised each time I discover some punky balsa. Mind over rot, my motto. That's why I have a plastic boat, that's why the plastic boat has me! NO rot, none, neit, nien, never, not.)
Last edited by ebb; 07-23-2003 at 08:05 AM.
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