Floating rebuild

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One Way David
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Floating rebuild

Post by One Way David »

Say one acquires a project boat and has to pay for time served on the hard but has free dock space once it floats. So the goal is to do as little as possible of the project on the hard. What to do? The obvious hull scrape, fair, prime and paint, replace thru-hulls, rudder and prop/shaft/packing work. So now the boat floats and can be towed to the free dock site and the rest of any work needed can be done.


If the interior needs to be gutted, would it be reasonable to use the original installations as registers because there cannot be a plumb and level measurement in a floating boat? Assuming that the original "felt" good to start with.

Would one make a register while on the hard to later use for plumb and level while afloat? Is there a plumb and level on a floating boat?

Or is a floating rebuild not feasible?

Dave.
Never finish all your projects or you'll be bored.
Quetzalsailor
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Re: Floating rebuild

Post by Quetzalsailor »

There's more than one way, David, to skin this cat.

Firstly, there's no guarantee that your boat would have been chocked flat and level. Secondly, there's no guarantee that the manufacturer's efforts are as good as a craftsman's as far as properly relating to a datum, or being square across the boat, or even symmetrical. You'll be on your own to decide what datum you'll want to work from.

Clearly, if the boat were stationary, then you could arrange a pair of levels, one for fore and aft and the other for transverse, with tapered shims to translate between what you decided a datum was and the attitude of the boat. If the boat's not stationary, then you have to set a datum by measurement from places in the boat that you've decided to trust. If you were sufficiently well heeled and inclined, you could rent a laser level of the sort that lay-in-panel ceiling guys use: set the thing up so that the rotating red path is parallel to your chosen datum. An ordinary surveyor's level would do as well but would require fussing and focusing, and a sidekick to observe or to move the mark, as well as the same sort of firm locating that the laser would. Otherwise, strings and measurements will serve perfectly well: the game will be in mounting and marking, perhaps with hot-glued pats of wood with string holes or simply marking indelibly on something which will remain visible until other objects and components are placed.
One Way David
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Re: Floating rebuild

Post by One Way David »

Thanks for the reply, Quetzalsailor. And then I think no matter how well the manufacturer or the craftsman (I'm being real bold to lump myself into this category) strive for plumb and level, the boat will not spend much time in the plumb and level position but will wallow in and out constantly.

Dave.
Never finish all your projects or you'll be bored.
One Way David
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Re: Floating rebuild

Post by One Way David »

I'm gonna bump this because I continue to think about it but in different ways. Some may consider it Technical Data and Boat Nurdery or Ramblings but I started out here with a different goal, to which I will continue after this brief hyjack.

Say one is able to set a boat up on the hard such that the waterline is close enough to level that a human, unaided by measuring devices, could not perceive any error in level. Suppose that construction went forward from that reference point and all decks, bulkheads, shelves, floors, tables etc. are true level and plumb to that perceived reference level. Next the boat is floated and continually rolls, pitches and yaws and spends some miniscule amount of time in the actual planes of true level and plumb and even less in both.

Since most would agree that human construction will not achieve true level and plumb, how far off true level and plumb could the interior structure be before it would be noticed without measuring devices in a floating ship.

I have read in finish carpentry books figures that the human eye can detect that are off level and plumb and just now read that humans perceive a slope of less than 5% as a flat grade. But what about in a rolling, pitching and yawing boat? Does length of time aboard the boat have an effect?

After a few minutes I come back to qualify and hopefully not inject a fatal requirement to my question. I am not looking to carry this discussion, should one develop, into neurology, physiology, psychology or paranormal directions. I'm more asking, if anyone should know, how good of a rule, level, or plumb line a human is and what effect constant mosion has on that.

Dave.
Never finish all your projects or you'll be bored.
Quetzalsailor
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Re: Floating rebuild

Post by Quetzalsailor »

Tsk tsk; you should be playing around the tree with your new tools! (I'm in exile with the grandchildren...)

As for perceiving straight and level, and writing as an architect: I think our eye and mind is(are?) very good at lining things up and recognizing shapes. We recognize level reasonably well by eye and very well by feel underfoot. We're very very good at projecting parallels and lines. Shapes out-of square are obvious to us. Asymmetry is obvious to us.

Moving on to your boat problem, bulkhead and paneling/door/edges/horizontals/verticals will be easily understood by reference to the symmetrical shape of the hull. Fore and aft levels won't be as important since the boat's shape is constantly changing. However asymmetry, non-coplanar and unhappily out of parallel (settee faces not prettily related to the perceived centerline) will be more obvious.

Sadly, lots of architecture by 'starchitects' today is 'designed' around fooling with human abilities and preferences for the straight and level, and the thousands of years of tradition.

By all means, suit your eye in design. If you have doubt and questions, build full scale models (cardboard or underlayment) inside the boat. Figure out the easiest way to assure adequate perfection. Sitting around inside the boat when all is done is not the time to notice that that counter is tipped relative to that other counter, or that the mast and head door are not parallel.
One Way David
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Re: Floating rebuild

Post by One Way David »

3 AM Christmas Eve I'm at work and not too busy. 7 am and I'm off to enjoy my grand daughter and the rest of the family. Grand kids, it doesn't get much better.

So your saying that the unaided sensations can detect square, plumb and level, probably in motion as well as at rest. Having done work, amateurishly, in the housing and furniture arena, I'm amazed at how much difference there is between the rough in and finish phase.

I also note that you mention the contrast of curves to linear. So on a boat, would the use/presence of curves in contrast to angles and lines tend to soften the detection of being off true or not? Being in a small space versus large?

These are thoughts that I have not run across before. Well, off for a week of fun and family.

Dave.
Never finish all your projects or you'll be bored.
Triton106
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Re: Floating rebuild

Post by Triton106 »

Dave, the PO of my Blossom installed a Newport cabin heater that was only a couple of degrees out of plumb and it bothered my for years even though it was hardly detectable if you don't look closely. What I am trying to say is that sometimes it will bother you (or at least bothers me) to know it is out of plumb even if your eyes don't detect it. I know there are plenty installations on my Triton that are not square or plumb but I will not knowingly add to that problem.
Ray D. Chang
Triton 106 in Berkeley, CA
One Way David
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Re: Floating rebuild

Post by One Way David »

Ray, thanks for the reply. This is just what I am looking for. I know the human eye (well some anyway) can detect out of plumb/square/level but have wondered how that applies to a floating boat that spends a minuscule amount of its time in plumb/level position.

I am not a seasoned sailor but with the little experience I have, I think I would see out of square fairly easily but have not noticed any attention (of mine) to plumb or level aboard ship.

Dave, thinking this subject may better belong in boat nurdery.
Never finish all your projects or you'll be bored.
Zach
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Re: Floating rebuild

Post by Zach »

Given you like the angle of the main bulkheads it is doable floating. It is hard if you let it be… there are some steps you can take to make it simpler and less frustrating. I’m doing the bulk majority of this floating. http://83footernoel.blogspot.com/

It is easier to do it on the hard and level… but if cost is an issue you can do it in the water.

At first blush everyone says to throw away your level, square, and plumb bob when you first step on a boat. That is because 90% of the time they don’t really show you much of what is going on, and you have to think in three dimensions to see what you are building. Squares give you a reliable edge to start using a bevel gauge. Plumb bob’s show you when your eye sees something, but isn’t quite sure what. Levels, help you to compare what is going on, but don’t really show you what to do next.

Strings:

You can do everything off a string drawn tight on the centerline of the boat from stem to transom. At the height of what you wish to build a surface… like a berth or cabinet. It is a pain in the butt to work around, but sometimes when you are lofting something that needs to be symmetrical it works quite well. When you are lofting a hull, you can measure from the string to the hull, and that is really the crux of what strings pulled on centerline are good for. Measuring to the inside of hulls, in a repeatable way isn’t done off strings very well… You need a center on a steel rule to pick up perpendicular to the string on its own. Most would just take a tape measure and measure out to the hull…

By that point you need a line on the bulkhead that parallels the waterline running across the boat, so you know where on the hull to measure to. Since you are floating, levels don’t work side to side very well with you moving around… It works, but it is a roundabout way to get there.

By and large the only time I pull string is to see how much curve something has over its length, or to pick up the centerline and mark it. Marks like that come in handy for centering up deck beams, or putting up plywood on the underside of a deck… and seeing lumps that are to big for a batten to find.

Here are some tips and tricks:

Take nothing for granted. Measure everything, and make sure your saw is set square or on the bevel you want when you pick it up.

#1: Start with the largest surfaces and parts when you are building. A goof up just means you made a little more scrap, as you can make the next smaller thing out of that board. Start at the ends and work to the middle. Buy all your materials you can think of and make the board footage minimums so you aren’t paying retail.

#2 Think through what you want level to be when you are done. What looks level fore and aft changes as you load your boat. You need to have a constant to build off, or everything will be different.

#3 Jigsaws are your friend. Get a T-shank style, even if it is a cheapie, it is better than the best U-shank. When the head that captures the U wears out it drops the blade. Bosch makes an excellent jigsaw that will hold steady a long blade and make quick work of long cuts. For plywood, it doesn’t much matter.

#4 Skill saws are nice. Dewalt and Makita make some of the best, as you can see the line where the saw blade is, and they don’t spray chips at your face. Craftsman, Hitachi, and Skill are alright. A Freud Diablo with a 24 tooth blade makes any saw a better saw for cross cutting. Speed squares are handy, and make the saw cut a perfectly flat and perfectly square end on something up to 8 inches wide. On thick stuff… the flange side goes on the far side of the board. If you are cutting fiberglass, throw on the cheapest blade or a metal cutting disk… fiberglass destroys pretty much anything.

#5 A low angle block plane allows you to plane the end grain of plywood without if fuzzing up and chipping out. A Stanley Sur Form plane (looks like a cheese grater) does the trick too, if you aren’t much for sharpening… yet. I keep both in my 5 gallon bucket with an organizer on the outside works well for a cheap tool bag if you have room to put it somewhere.

#6 2 cordless drills that share the same batteries, and a spare set of batteries that are charged or on the charger. For one, you will want a GFI on your extension cord if you are working on the side decks with a corded drill. What I like about cordless drills is that when you let off the trigger they stop, quickly. When you are driving a square drive screw in you can feel the point right before the head snaps off… and let off the trigger. With a corded drill, they keep running for a second and you have to yank the drill out of the head (sometimes unsuccessfully…) which normally buggers the head of the screw.

Keep one drill with an 1/8 th inch drill bit, and the other with a long #2 bit driver, and a short #2 clipped on the body of the drill. Now you can hold a cleat in place… pre-drill the hole, grab a screw and set it on the #2 bit, and drive it. Otherwise you have some time spent re-finding where the cleat went between swapping your drill bit back and forth.

#7 Buy #2 bits by the 10 or 25 pack. Throw the bit away as soon as you can see that the tip is no longer square, or the first time your screw wiggles around while you drive it. Bits are cheap, and a buggered up screw head that didn’t pull down tight makes for a pain in the butt on anything you care about.

Thinking about the boat, and how to build what is inside:


Get the boat floating on the line you want it. Fill up the fuel tanks, water tanks. Buy the anchors, build the chute… put in the chain. Or guesstimate what the weight and location of those will be and put on sand bags. As you build in stuff, she’ll sit lower in the water, but you have to think about where the weight is going so she stays on her lines.

With her on her lines… make a wedge out of wood that you can glue somewhere out of the way, with a top that is level fore and aft, and side to side. Screw, or tape a level to something vertical like your companionway… and adjust some weight until the waterline shows it is right.

When things change make a wedge for your level. Check your pad, after you put on stuff that is heavy. Think about when you step on the bow of the boat, it goes down. If you weigh 200 pounds, its going to go down when you scatter a lot of plywood around.


#3 Bulkheads: On the same perfect day you make your wedge, Hang a plumb bob to mark the angle of the bulkheads to see how far out the bulkheads are from plumb while on the waterline. If you want to make it easy, and don’t have a sole that runs out right to the bulkhead screw a shelf on to the bulkhead keeping it square to the face exactly 2 or 3 feet down. Put the string for the plumb bob at the top inside corner, and mark its location on the shelf. Measure off the bulkhead to your mark, and jot it down. Now you know that over 3 feet your bulkheads run out three quarters of an inch. If you think this one through, that means one side of your bulkhead is a real steep hill, and the other side is an overhanging cliff that would be in the shade at high noon…

That means that the cabinets should be square to the bulkheads right? Wrong… They both should appear to be plumb to the world… not the bulkhead. Otherwise while your boat sits on the lines your sink won’t drain out of the corners.

If your bulkhead runs out three quarters of an inch over 3 feet, that means that if you made a cabinet on both sides of the bulkhead square to the bulkhead 3 feet out on each side… that the height of the aft end will be One and a half inches higher than the forward end. This over 6 feet will really goof with your eye.

Now imagine that was your sleeping berth… It’d be an inch and a half high at your feet for a 6 foot berth. Your berths should be 6 foot 6, to 7 feet depending how tall you are.

So, what you do is work out the slope formula… or bevel angle, so that when you draw out a side for your cabinets, or the wall for a hallway, the aft corner will have a slope that is repeatable. As they are all the same slope. Make a template of your angle, 2-3 feet long, and 8 or so inches wide. Use a factory edged piece of plywood, and mark a centerline in the middle with a combination square. Move your top mark over an inch, so it is easy to measure to your centerline when you make a template… and measure out how far the plumb bob went at the bottom. Mark these two points and use a straight edge… then cut it out with a jig saw. Depending on which side of the bulkhead you are on, flip it upside down or right side up.

This template is the angle it takes to make a perfect fit to the bulkhead… Right? Nope… That would only work if your cabin sole was perfectly square to the bulkhead. Most of the time your cabin sole runs down aft, as boats get narrower going forward and higher out of the water in order to get useable space the sole has to go up.

To see what the intersection of cabinet side and sole does, you need a bevel gauge; a thin piece of metal in a square handle, with a pivot and a locking nut. You pivot the metal to where the handle and metal are touching each surface, and lock down the nut. Then you mark the angle on a piece of plywood with a factory edge, so when you bump it on the way to your saw you don’t have to contort yourself back into position.


You need to have 2 or 3 bevel gauges of different brands to do big compound miters for mast beams, stern posts and the like. Lose one overboard, drive to the store for a 4.99 cent tool. Step on it… throw it away, 4.99. Forget it’s in your back pocket and tear apart the boat… 4.99. Make sure that the metal stays flush to the handle on acute and obtuse angles… some brands don’t.

Unless you draw what you are going to cut, and mark on a story board (Straight sided piece of plywood...) the angles of all sides, and what they all go to. I find it easier to jot down which color bevel goes on which side of the cut. Your bevels get marked and cut, before your overall length gets measured and cut.

How to scribe something to fit: Cut the pattern out 2 or 3 inches larger in all dimensions than you’ll end up with. If its sitting down onto the hull, mark a line that is plumb on the bulkhead it butts. You can screw a temporary cleat on one or both sides so you can drop it into the same spot every time. Hold a framing square to the bulkhead, and hold the pattern square. Mark the hull with a marker and hot glue a block to the hull so you have a reference mark like a third hand.

Now take a pencil and a block that is an inch or two square, and ride it along the hull marking as you go. You can’t bump or have a loose pencil on a block. Anywhere you mark a block, will be that distance from the hull. Compass are nice, but take a light touch to be repeatable. So long as the block is an inch square or two inches square, it’ll fit into the radius of the hull. If the block falls through at one side, mark where you can and cut off to your line with a jigsaw and mark it again. When you get close, take a sharp pencil stub and lay it on the hull to mark it.

Compass: Don’t bother with a school style compass, go get a Groz brand one for 15 bucks that doesn’t flex and will hold your setting. You’ll need it for doing round stuff, transferring cambers and such…

If you like a compass, try laying it all the way flat to the surface you are scribing (a lot easier if there is a cleat to ride on) as that removes the ability to change the radius by not holding the compass perpendicular to the surface. This radius change isn’t much in the middle of a piece, but at the end if your concentration wanders you’ll round the edges and make it fat.

You can also use a compass as you would spiling a plank on a wood boat. Hold the point against the first plank, or index mark on the frame where the next plank will be, and swing an arc on your template. The highest point of the arc, is the spot which you are using as a mark. That means you can scribe a football shaped hole with pointy ends…

Back to cabinets:

From here it is a matter of deciding on the height of your cabinet, and mark it on your bulkhead, or vertical. Mark the width of the top of the cabinet. Measure off the edge of the plywood that touched the bulkhead… Put your pattern that showed the angle difference between what the bulkheads are, and what “plumb” looks like.

Since we know what the forward or aft corner looks like… and we know how big we want the cabinet top we want, we draw up a full scale template of the forward and aft side. We leave a square corner on the front lower corner, and front top corner and cut the piece 2 or 3 inches taller than it needs to be, and 2 or 3 inches longer than it needs to be.

Now we are going to scribe it to fit.

Lets say this cabinet runs athwart ship (across the boat) 2 feet wide off the bulkhead, may be 22 3/4 inches from the bulkhead at the top to appear plumb, while the bottom is 24 inches full. Or vice versa, depending which way your bulkheads lean. You are working to the finished side, or the outside corners... So cut that side, and then leave 2 or 3 inches on the bulkhead side. You'll set the side of the cabinet on the sole, and slide it till it bumps the bulkhead. Lay a straight edge against the bulkhead, If it doesn't overlap the side the whole length, take a jigsaw and cut off a little bit of the “point.” Move it over, and when the straight edge touches everywhere, mark the side of your cabinet. Measure from the aft end, 24 inches... Measure how far it is from your line, to your mark. Make 2 or 3 marks the same distance off the line, lay your straight edge, make a new line. Cut this with a jig saw just leaving the line. You now have a cabinet side that is 24 inches from the bulkhead, running at the angle on the face it needs to appear to be plumb... With a factory edge on the bottom, and fit on the bulkhead you can't slide a piece of paper through.

If you are scribing to the side of the hull, my trick is to make a portable bulkhead I can set on the cabin sole (floor) that has the bevel of the bulkhead on one side, and a square side on the other. I take a piece of 3/4 plywood about a foot square, and two pieces that are about a foot wide and 3 or so feet tall. On one side I leave the bottom square, and screw it to the end grain of the plywood. I mark the bevel of the bulkheads on the inside face, and lay the other 3 foot tall piece on this line, screwing it to the face and the endgrain of the foot square piece. Basically just a 3 sided box.

What I do is measure off the nearest bulkhead, or other big square flat faced looking object that is near by... and set this rig on a line drawn on the cabin sole. I screw it down, and screw a piece of luan to the face. From here I tick stick the hull. Because one side is square, I leave the luan overlapping the edge and mark it from the back side. This line is plumb to the sole. The bottom of the rig is flat... So the outside corner is square.

I go and take my piece of luan, and repeat the tick sticking as described earlier. Now I mark the end grain of the luan where the jig was, and bump it an inch inboard of the edge of the plywood so I have wiggle room on my new plywood. I warp my batten, make my cut on the plywood and cut it out. Take it down to the hull, and slide it in place against the jig. Now take a compass with a pencil and set it to about 3/4 of an inch, and ride the point on the hull and pencil on the plywood. Go cut the pencil line, and you should have a perfect fit. Now your face side is a 1/4 fat of the depth you wanted off the hull. Wiggle room if it wasn't perfect. Rip it off on a table saw. Now screw this down to the jig. The other side of the jig, is square to the floor and the lubbers line. Take an aluminum straight edge and mark the hull or whatever the face of the cabinet will run out to...

On big stuff, like a built in V berth, take a bucket of water and get the water level at the berth height you want... put a clear vinyl hose in it and use it as a water level. If you are not level side to side, mark what you have in pencil, and then measure down from the deck or up from the sole close to the lubbers line. Cleat out the front and back, square to the opening of the bulkhead if they are plumb, if not... eyeball it to the average of your marks. and make a bridge of 3/4 plywood 6 inches or wider across it. Take a 4 inch piece ripped on the tablesaw and screw it to the underside so that everything is straight. Now take an aluminum straight edge and run it out to the hull, and mark once every 3 inches or so. From here you can either cleat out the hull, and build in a box along each side making the side of the berth straight, or tick stick it to the hull.

I make my tick sticks with curves, squares, swoops and v grooves so that I can't be dumb and forget to mark which v cut was which. Take a piece of luan on your plywood bridge, and screw it down. Mark the bottom, on the edge of your bridge so you are inline to your lubbers line. Now Mark every 4-6 inches on your luan, along the side of your stick. Do both sides of the hull... so use a wider piece of scrap luan and a shorter tick stick. I try to keep my tick sticks shorter than 3 feet, so I can see both sides of the hull on the story board. (the luan) Mark the bulkheads. They may be plumb and square, but your bunk isn't square to them... Which means that your bunk will be a parallelogram with curved sides...

Take your luan up and lay it on a piece of junk plywood 1/2 or 3/4 inch thick so its straight-ish. Mark the end grain of the luan at the centerline mark you made earlier. Mark the centerline on the plywood. If you have one side that can use a factory edge. This will be on of your bulkheads, or the side that faces the walkway... You find this by sliding your story board on the plywood, and watching your tick stick until the point is just on the edge of the plywood. Now scootch the template in another inch. You can always rip off an inch... if you don't leave some slack, you'll have a loose template and need to mark the top faces. Mark the plywood the rest of the way around with your tick stick and a sharp pencil.

Now take a batten and warp it around. Wood battens are best, as they take a natural curve. Metal battens are nice for tight detail radius (Think a thin steel rule...) Your batten is just a piece of wood that the grain doesn't run out on, and doesn't have any knots or hard spots. It will lay straight, and not have bows or big crooks in it. I use a lot of pine, so most of mine are... pine. Juniper is the best for big radius like transoms, and toe rails. Ash is nice because it can be thinner, which means it takes less work to bend. Douglass fir is the norm... but don't go and buy a board if ya don't need to. I've made many a one out of a spruce 2x4 ripping it into 3/4 wide strips and throwing away the wonky ones...


After you've been doing this stuff floating for awhile your eye will be able to see the difference of angles. People see if things run at different angles on everything, and they also see if walls lean away from them. Most stuff on boats ends up having the face be closer to you at the top, and just a little further away at the bottom. When everything else is curved, it takes some creative liberties to make things feel square to people. That is why folks say to throw away your squares and levels. Which is mostly good advice. About the only time I use a square is to define a line off a known good bulkhead, perpendicular to the centerline of the boat running fore and aft.

The sole runs at a different angle from the waterline, but... it should be level side to side with the waterline when she is trimmed right.

Tape measures suck for doing tight fitting, so a folding extension rule comes in handy. I do a lot with plywood jigs, where you cut a U or a Z shaped piece of plywood that defines the shape you want something to be full scale, and move it along the face surface of what you are working on and fudge the cleats until the desired shape is there. A story stick is another good on… Rather than a tape measure and a pad of paper to draw out the shape and dimensions, mock it up on a straight stick drawing the intersections and bevels. This is a real nice thing when you are making a few of the same piece. No measuring!

The other thing that a lot of folks don't realize is that plywood isn't flat when you cut and work with it, standing it straight up and down in a hull. I screw 4-6 inch long strips of plywood on edge to the back side, canting one at a different angle so that the door ways stay straight, and the line at the hull stays perpendicular to the centerline.


Zach
1961 Pearson Triton
http://pylasteki.blogspot.com/
1942 Coast Guard Cutter - Rebuild
http://83footernoel.blogspot.com/
JohnD
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Re: Floating rebuild

Post by JohnD »

Wow, thanks for that right up. While kind of a long read, it had a lot of good information and tips I will be using in the very near future. I'm also dealing with renovating a boat in the water. Kind of a strange problem to have...its free to leave it where it is at the marina, but more money than I have right now to have it pulled and stored. Makes for some challenges, that's for sure.
One Way David
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Re: Floating rebuild

Post by One Way David »

Wow is right. Zach, that was a nice write up. I can see there is a lot of finish carpentry technique in there that I'm familiar with but your discription in terms of the not so square/level/plumb'ness of a boat is very helpful. Thank you. Scribing, tick boards, storey boards and inside rules are familiar. I'll spend some time thinking and experimenting with the balast concept of setting the floating boat to water line with full/partial full stores. That concept had not even entered my thought processes other than it is a constantly changing factor. But to make it a starting point for data works. Using a bucket of water to set a starting data point is a neat idea also. The bucket can be marked and as long as it is set in the same place with the correct amount of water, it can be used as a fixed datum. I'm sure I'll read through this a few more times, I always get something more with each read.

Dave.
Never finish all your projects or you'll be bored.
One Way David
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Re: Floating rebuild

Post by One Way David »

Ah Ha! Now I'm getting somewhere. I do read and I do do research before I come here to post my questions.

I was over at Tim's site on the Motorsailer http://www.fisher30.lackeysailing.com/l ... 13011.html
and I am reading Tim's narative. And there, in front of me is the answer in 2 closely related paragraphs.
Asymmetry is common--no, universal--in boats, at least boats on which I've ever worked, but somehow it seems to rear its not-so-pretty head in unexpected places. One takes pains to lay out new structures in careful and measured ways, yet somewhere during the process some oddball asymmetry or another is bound to turn up.
and
Around and about this time I also determined that the cuts defining the passageway on the original bulkhead were not plumb either.
Tim's boat is blocked in his shop and I imagine as close to level and plumb as a human could put a boat. Now I can approach my project with confidence that it will not be plumb or symmetrical.

No Zach, i didn't for a minute doubt you. It is in my nature that everything has to be confirmed by separate sources.

Dave.
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Re: Floating rebuild

Post by Rachel »

One Way David wrote:Tim's boat is blocked in his shop and I imagine as close to level and plumb as a human could put a boat. Now I can approach my project with confidence that it will not be plumb or symmetrical.
David,

I might be interpreting what you're saying wrong, and if so please excuse me. But, although Tim and others have noted that the original boats and bulkheads are often not plumb or symmetrical, I believe he and others who have re-capped their re-fits here do make their new installations plumb/square. Unless sometimes they decide not to for reasons of accepting what is and matching it, etc.

I just mention that because as I was reading your post it slightly sounded like you had taken away that people were putting in new work that was off-kilter. Maybe you are just saying that you won't be surprised when the existing boat is out of plumb?

Does make new house building seem so simple all of a sudden, doesn't it? ;)
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Re: Floating rebuild

Post by Tim »

Like Rachel suggested, David, hopefully what you're taking away from the sections you quoted above is that original structures tend to contain inaccuracies that will pop up from time to time, even if the basic installations are fairly accurate.

The layout issue you reference seems to be the result of an overall asymmetry in the shape of the hull and/or deck molding on this boat, not the interior structures--old or new. There's simply nothing one can do about a tooling inaccuracy, but I've yet to work on a major project on any boat where these issues didn't arise.

In any interior project, one must take pains to choose an appropriate reference point from which the remainder of the interior can come together in an accurate way. Whether that point is perfectly level or plumb or symmetrical according to the Earth's axes or magnetic fields or whatever one calls the "best" reference point is ultimately less important than the fact that key structures and interior components are accurately aligned to a common datum, which ensures that things work right and look "right" to the eye.

I chose to highlight the issues I discovered as a point of amusement and interest--and inevitability. They don't affect the interior construction or layout at all in this case, but the point is that sometimes what you think is symmetrical simply isn't. This helps one keep the whole project in the proper perspective. Perfection doesn't exist, but one can strive towards it within the bounds of reality.
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Re: Floating rebuild

Post by One Way David »

Rachel, having read most of this site and most of Lackey_dot_com site, I recognize that Tim and others here have a knack of doing things about as well as they can be done. I sure hope that I haven't implied otherwise and if that impression came across I apologize profusely.

My main focus in this and the sequel posts is to plan my upcoming floating rebuild. To whatever degree that turns out to be.

I crewed out as a helper on my major house remodel. The "contractor/crew chief" said once about my complaints about something or other not being square enough or whatever, "That's why they call it rough carpentry". He pointed out that it was the job of the finish carpenter (me) to fix his inaccuracies.

So, it boils down to what Tim says above, "Perfection doesn't exist, but one can strive towards it within the bounds of reality." And that seems to be that "which ensures that things work right and look "right" to the eye." I think this sums up my attempts to put a number/measurement on how close one has to get to "perfection" to be acceptable.

Dave.
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Re: Floating rebuild

Post by Rachel »

Hi David,

It sounds like I misunderstood what you wrote. How that happened was that it sounded to me like you were saying that having things come out off-kilter on your rework would be okay, and then citing examples of work members here were doing on re-fits as "backup" for that conclusion. But in those examples the new work was "on kilter" and it was the original boat construction that was off-kilter. So that's where I got off track in interpreting what you were saying. Sorry about that.

Rough carpentry (I think of this as framing; not sure if that's officially right) in a house is a nice thing, isn't it? Because, like you say, you can then install the windows/cabinetry/whatever precisely within it (as long as the framing was within a certain tolerance). I don't feel like our kind of small fiberglass boat interiors provide quite the same sequence though, because the "framing" (i.e. bulkheads, flats, and the like) really are the finished work. Or close to it. At least how I visualize it, you don't get to go back and use shims and such to put your final structure within the "framing" and then put millwork over the gaps in quite the same way as you do with a house. (I'm using "framing" in quotes to refer to rough house carpentry framing, not wooden boat frames.)

I think I do understand where you are coming from. Because you are doing a floating rebuild, you can't just level the boat and have it stay that way, as you could on stands on the hard.

Rachel
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Re: Floating rebuild

Post by One Way David »

No doubt that my post could be read that way.

Your comment on rough framing is exactly my issue. Here the rough framing is the lay up of the hull and deck. The finish carpentry is everything else.

I have this concept that I can do anything. Well, almost anything. I just build my learning on past experiences. The fatal error in this concept is that, just like in "Bonfire of Vanities", just because you think you know, just because you think you are the master of the universe, the universe may just have another opinion.

So in my case, since I will have the boat on the hard long enough to do the hull work (and the goal is to keep this to a minimum), I will need to fix the data points for plumb and level for future reference while afloat. This will have to be done without the demolition that is commonly seen in a rebuild but accessible enough that regardless of the degree of demolition afloat later. This will require sufficient detail in setting the boat plumb and level to the waterline on the hard so that later while afloat the data points will correctly reference as close as possible to plumb and level.

Hence the question; How close is close admitting that no hull is symmetrical and therefore the waterline is not just a mathematical equation. In addition, the waterline may very well change depending on the design of the interior and systems.

And the answer; Close as is right to the eye. At least that is what I think I get from Quetzalsailor, Zach, and Tim above.

Maybe this post belongs in Ramblings? Thinking and talking through this does help so thanks for all of the input from everyone.

Dave.
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Re: Floating rebuild

Post by Hirilondë »

One Way David wrote:
Hence the question; How close is close admitting that no hull is symmetrical and therefore the waterline is not just a mathematical equation.
42

Actually, the designer probably did calculate the water line using math.
One Way David wrote: In addition, the waterline may very well change depending on the design of the interior and systems.
Your boat may sit a tad lower after adding to the interior, but it she sits significantly different than intended you really messed up. If you are adding or moving heavy things, you really should consider the implications before proceeding. You don't need to do serious calculations most likely, but if you are adding heavy things then some thought to evenly distribute the weight for and aft as well as port and starboard is in order.
Dave Finnegan
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Re: Floating rebuild

Post by One Way David »

Dave, thanks for the reply. I had thought of added weight in the form of enlarged holding and fuel tanks. Until I pick the boat however, I will not know if the berths, salon, galley or head will change much. Probably not. As I read here, I have noted comments that consideration is given to balancing the added weight.

In my mind, another feature, if one sticks to almost-original-layout, is provisioning and storage areas that one may decide to make.

And yes I will admit, if I think about it, that an architect would use every mathematical means available to him/her to design his vessel. I guess what I was referring to was my impression of what changes in those figures some of the re-designs might make. For instance, gutting to bare minimum for race weight across the Atlantic (a blog about a build that I doubt that I could find now), removing an engine to sail-only status (eg. Atom), adding every conceivable gizmo to a 1960-70s built boat (electronics, hot/cold pressurized water, desalination, gensets...). It seems logical that one would consider weight added/removed/moved in these situations but without the architect's data one would be in a trial and error mode, right?

Dave.
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Re: Floating rebuild

Post by Zach »

New tool...

2x3 aluminum box tube. 1/8th inch wall... It is straight, and comes in shots up to 23 feet long.

I've been using it lately to fit out some door frames that are recessed along one of the walls in Noel an inch and a quarter. The bulkhead is 8 inches thick, so while it was plumb to the rest of the world it was racked out of line to the walkway. Since the walkway follows the boat from port side to the center going forward the wall opposite the door frame tapers so a width measurement over 8 inches didn't quite do the trick not to make a parallel door frame.

So, an 11 foot long piece of 2x3 box tube extended the line of the wall that makes the inboard side of the stair case forward to the recessed door frame. A block of wood ripped 1 1/4 wide was taped to the box tube and power planed a few tracks at the top, middle and bottom to the right shape allowing me to plane to shape the piece of 3/4 plywood that skinned the opening in the bulkhead.

It also seems to work quite nicely across door jams to glue up new panels straight. Ideally you would cut a wall including the 3-4 inch tall piece of plywood across the opening out of one sheet of plywood... but if your walls are wide enough there isn't enough width to do it. Segmenting a doorway into three pieces means the two outer panels can be out of line, and the top header is askew too... A straight edge that is made of flat bar flops down and bends, when things are flat and true unless you've got a third or fourth hand to hold everything square.

Anyhoo, I thought about this thread during the process and figured I'd put it out there in case it helps someone down the road.

Cheers,

Zach
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Re: Floating rebuild

Post by Vark »

My 2 cents.................
It can actually be easier working on a boat that's in the water especially if you set up a work shop / area close by. It's certainly easier stepping on to a boat from a dock than climbing up and down a ladder all day as in a shop or on the hard.

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Re: Floating rebuild

Post by jollyboat »

. . .um, we are talking about an Ensign right?
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Re: Floating rebuild

Post by Tony »

I attempted a floating rebuild several years ago on a 32' Ketch that got abandoned and sold mid-build for relationship reasons (too bad). One thing I would point out is that unless your boat is extremely overbuilt, the hull will tend to sag if you demo the original cabinets, etc. without providing some other form of support. (I learned this the hard way). I recommend putting in some horizontal and vertical supports to hold the shape of the hull while you work on it. It's much harder to pull the hull back into shape if you don't.
Tony
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