Riveting w/upside down build

[jalmberg]

As my first boat building project, I'm building the traditional, lapstrake Atkins Cabin Boy, a 8' skiff.

The plans call for it to be built on forms, upside down, with the planks fastened with copper rivets.

Some old photos I have show that the heads are counter-sunk on the outboard side of the boat, and then plugged for a smooth finish.

This means that the 200+ rivets need to be peened on the inboard side of the plank.

It must be pretty awkward to climb under the boat, between the forms, to finish off all those rivets (presumably with a flashlight clenched between the teeth, so you can see well enough to do a good job.)

Am I missing something, or is this how it is done?

Hoping for an old boat-builder's trick...

-- John

[Eric D]

first off, get a head lamp used by hunters/joggers/outdoor's type people and save the teeth. My wife the hygenist would be so proud of me right now...

http://www.zombierunner.com/store/categories/flashlights/product1257.html

this is an incredible light worth every penny and more. You will use it darn near weekly around the house doing odd jobs let alone on the boat once you have it built.

otherwise, i have no tricks for the job, looking forward to reading your progress and the tips real builders give you!!

[Jay Greer]

What you speak of is one reason I have a pit under my building area in order to allow the riveter stand at a comfortable height. Fuller makes a flat counter bore for sinking nail heads if you wish to plug the planking. Another method of working is to lean into the hull from the out side in order to reach and peen the rivets. Either way is a pain in the neck.
Jay

[DGentry]

Am I missing something, or is this how it is done?

Well, you forgot a helper, who gets to back up the rivets with a heavy piece of metal while you peen them over . . . .

Or, you could do it the non-traditional way: glued plywood lapstrake. No rivets at all.

http://ecx.images-amazon.com/images/I/51VrbX4fY2L._BO2,204,203,200_PIsitb-sticker-arrow-click,TopRight,35,-76_AA240_SH20_OU01_.jpg

Good luck!

[Peerie Maa]

Why not just build it the right way up. We've been doing it for about 1200 years quite successfully.:D

[Jay Greer]

West System makes a new flexible epoxy that can be used for plank gluing. This is the way that "Vapor" is being done. However I would not be entirely comfortabnle with glued lap streak construction.
Jay

[2MeterTroll]

and if you need the upside own perspective just hang upside down from the rafters.

[jalmberg]

Either way is a pain in the neck.
Jay

I think so. Guess I'll have to try it and see if there's enough room to swing a hammer.

I guess a third alternative is to use counter-sunk screws, applied from the outside, rather than rivets. More expensive, but maybe worth it in terms of time and pain.

-- John

[jalmberg]

first off, get a head lamp used by hunters/joggers/outdoor's type people and save the teeth. My wife the hygenist would be so proud of me right now...

An excellent idea. Thanks!

[jalmberg]

Why not just build it the right way up. We've been doing it for about 1200 years quite successfully.:D

H'mmm. That's a possibility, I guess... Have to think how I'd set it up...

[Paul Scheuer]

You will be building with cedar, right? Probably want to paint it. In that case there's no need to counterbore for the rivet heads. They'll sink into the cedar as they are set. There's probably also an option to clench nail the laps. The Yankee Tender can be built either way. I did clench nails, so the hammering was done on the outside, with the buck on the blind side. I did do a varnished mahogany sheer strake, so I painted a one inch accent stripe at the lower edge.

I'd suggest setting up the building form high enough to allow for lighting.

[Mrleft8]

When I built "Marjie B" I planked and "nailed" the planking with the copper nails with the hull upside down on the forms, then pulled the hull off the forms (No, it wasn't that easy, but do-able), clamped the shear together to put on some temp cross spauls, and then invited 3 friends that I'd never met before to come over for chili and rove setting. Worked like a charm. :D

[Brian Palmer]

A small boat like that, you can probably just turn the whole building form over and then rivet the plank laps standing up. No need for floor pits and head lamps. Save your back and knees, too.

Brian

[rob]

riveting upside down is a pain, if your roves are a press fit, you can nail and rove, but wait to rivet until you roll the hull.
Generaly if I am going to rivet a boat I build her right side up. You need to be able to set up braces for the molds from the cieling or from a long braced beam like a strong back hanging from the cieling...the set up is a bit more involved, but it makes riveting very doable by yourself (assuming you rivet each plank as you go). It also make lining off easier for those with less experience, it's just easier to see the run of the line in proper orientation. The drawback is that fitting garboards and broadstrakes is more akward. Another advantage to building right side up is that you can leave your some molds in place while framing almost all of the hull, the additional support can be nice depending on you frame size.

[James McMullen]

With a boat as small as this, there is absolutly no reason why you can't just nail it together, leaving the rivet nails long, and then put on the roves and peen them once the boat is rightside up. You'll be able to suck the laps in tight, no problem if you learn how to rivet correctly.

I myself prefer to clench nail the planks together and only rivet through the frames which are put in once the boat is flipped over. . .but there is certainly no one right way to do it.

[dmede]

Upside down is how I built and riveted Atkin's Maud & Emeline. Judging from Cabin Boys lines I'd guess that you will be riveting before the bottom goes on which means you can do most of the riveting looking down on the hull from above. With a little boat like your it will go quite fast and is not at all as difficult as it seems.

If you are using a soft wood like cedar you will not need to drill counter sinks, the peening hammer is enough to drop the nail head just below the wood surface.

http://farm4.static.flickr.com/3132/2711082108_7a0731eced.jpg

[rbgarr]

If I understand the situation correctly it's a non-issue unless the building jig isn't set at a comfortable working height (the chine between elbow and armpit level).

Cabin Boy is a 7 1/2 foot flat bottomed skiff with relatively upright sides. You'll be planking the sides first and will have good access to the roves for peening before planking the bottom. It will actually be an easier fastening job than if the boat were right-side up because you can hold a backing iron downward against the nail head with your body as you cut and peen the rivets. Frames and screws to hold them go in after you've lifted the boat from the mold and tuned it over.

Good luck.

http://www.boat-links.com/Atkinco/Dinks/CabinBoy.html

(edited to add: cross-post with dmede)

[holzbt]

[QUOTE=dmede;2324342]Upside down is how I built and riveted Atkin's Maud & Emeline. Judging from Cabin Boys lines I'd guess that you will be riveting before the bottom goes on which means you can do most of the riveting looking down on the hull from above. With a little boat like your it will go quite fast and is not at all as difficult as it seems.

If you are using a soft wood like cedar you will not need to drill counter sinks, the peening hammer is enough to drop the nail head just below the wood surface.



This is good advice. You can hold the backing hammer with one hand outside the boat while you swing the ball peen inside to head up the rivets. If you need two hands inside to set the roves you can tie a line to the backing hammer and hang it around your neck and then hold it in place with whatever part of your body happens to be at the right height. I usually set the rove with a heavy set so that I can just hammer the nail in from the outside drawing the rove down tight This will only work if the I.D. of the rove is slightly less than the O.D. of the nail.

[Paul Scheuer]

That'll be a nice project.

What's the plan for the bottom planking ? Double cross planked ? If so, the inside layer will go on before the garboards. You'll have pleny of experience with clench nailing by the time you get to the planking.

http://i306.photobucket.com/albums/nn278/PaulScheuer/CabinBoy-1.jpg


http://i306.photobucket.com/albums/nn278/PaulScheuer/CabinBoy-2.jpg

[rob]

I hadn't paid attention to the design. Folks is spot on that riveting will be a breeze before the bottom goes in either way.

[jalmberg]

I'd suggest setting up the building form high enough to allow for lighting.

Ah... now there's an obvious idea... build longer legs on the forms for more light/room. Thanks.

[jalmberg]

When I built "Marjie B" I planked and "nailed" the planking with the copper nails with the hull upside down on the forms, then pulled the hull off the forms (No, it wasn't that easy, but do-able), clamped the shear together to put on some temp cross spauls, and then invited 3 friends that I'd never met before to come over for chili and rove setting. Worked like a charm. :D

That's a thought... if the nails held good enough to hold the planks together until the boat is removed from the forms, then rivet right side up. Perhaps clench a few so the planks don't separate. Interesting idea. Thanks!

[jalmberg]

A small boat like that, you can probably just turn the whole building form over and then rivet the plank laps standing up. No need for floor pits and head lamps. Save your back and knees, too.

Brian

This is what I was thinking last night... build the forms, build the backbone (stem, keelson, bottom (flat), transom)... make sure it's all solid, and then flip her over... If I don't come up with a better idea, this is what I'll probably do. Thanks!

[jalmberg]

Upside down is how I built and riveted Atkin's Maud & Emeline. Judging from Cabin Boys lines I'd guess that you will be riveting before the bottom goes on which means you can do most of the riveting looking down on the hull from above. With a little boat like your it will go quite fast and is not at all as difficult as it seems.

Wow! Another interesting idea... leave the bottom off. Duh! Why didn't I think of that? Thanks!

[jalmberg]

This is good advice. You can hold the backing hammer with one hand outside the boat while you swing the ball peen inside to head up the rivets. If you need two hands inside to set the roves you can tie a line to the backing hammer and hang it around your neck and then hold it in place with whatever part of your body happens to be at the right height. I usually set the rove with a heavy set so that I can just hammer the nail in from the outside drawing the rove down tight This will only work if the I.D. of the rove is slightly less than the O.D. of the nail.

I don't think I can peen them blind, though. Unless it's a lot easier than I think.

[jalmberg]

That'll be a nice project.

What's the plan for the bottom planking ? Double cross planked ? If so, the inside layer will go on before the garboards. You'll have pleny of experience with clench nailing by the time you get to the planking.

http://i306.photobucket.com/albums/nn278/PaulScheuer/CabinBoy-1.jpg


http://i306.photobucket.com/albums/nn278/PaulScheuer/CabinBoy-2.jpg

She's a beauty, eh? A real Atkins in miniature.

Clemens Kuhlig, who wrote the book on this boat, used plywood for the bottom, rather than planking. He put the bottom on before planking the sides, which is what brought me to this question...

He riveted the planks as he went along, using the 'blind peening' method, I guess, because there's hardly room between the forms to squeeze under.

It never occurred to me that you could reach in and peen them by feel or intuition, but I guess with experience it's possible. I have a hard enough time hitting the head of a nail, so I'm definitely going to need to be able to see what I'm doing.

So it sounds like there are two good solutions for me:

1. leave the bottom off til the sides are done
2. drive in the nails and then flip her over to peen.

Excellent ideas, guys. Just what I was hoping for.

Thanks: John

[holzbt]

http://farm1.static.flickr.com/150/360548361_ffca51298d.jpg

http://farm1.static.flickr.com/163/429931787_f8bb92dec0.jpg

This is DMEDE's setup. You should use something similar. As you can see there is plenty of room to rivet. All your rivetting should be done before the bottom is planked. If you don't need the storage or ability to move the building jig just make the legs of the molds long enough to fasten to the floor or ladder frame and have the boat at a comfortable height to work on.

[holzbt]

I don't think I can peen them blind, though. Unless it's a lot easier than I think.

Nothing blind about it. The flare is not very great so you just lean over enough to look down and see inside the boat. It's actually much easier than you are apparently imagining it. The boat is built upside down. The chine should be about waist height or a bit higher.

[jalmberg]

Here is the photo and instructions that prompted this question... He must have been peening blind. I just couldn't imagine doing that...

By the way, the forms are only 22 inches apart. You gotta wonder how he put the sheer plank on!

http://www.identry.com/downloads/master/cabin_boy.jpg

[jalmberg]

Nothing blind about it. The flare is not very great so you just lean over enough to look down and see inside the boat. It's actually much easier than you are apparently imagining it. The boat is built upside down. The chine should be about waist height or a bit higher.

Right, if you leave the bottom off. That was what I was missing.

[rbgarr]

I don't see any advantage to putting the bottom on before planking the sides, or double planking it. The bottom (plywood or planked) on a flat bottomed boat will most likely need replacing before the side planking given normal wear and tear.

Why would anyone want to unfasten and remove the garboard on a lapstrake boat, or unclench bottom nails, in order to remove and replace the bottom? Hell of an unnecessary bother.

[jalmberg]

I don't see any advantage to putting the bottom on before planking the sides, or double planking it. The bottom (plywood or planked) on a flat bottomed boat will most likely need replacing before the side planking given normal wear and tear.

Why would anyone want to unfasten and remove the garboard on a lapstrake boat, or unclench bottom nails, in order to remove and replace the bottom? Hell of an unnecessary bother.

From an earlier picture in the book, it looks like Kuhlig beveled the plywood bottom to achieve a tight fit with the garboards.

That raises an interesting question about leaving the bottom off till the planking is done... How do you get a good fit between the bottom and the garboards if the garboards are already in place? Just leave the gap, or fill it with something?

[rbgarr]

What 'gap'? The bottom overlaps the lower edges of the garboards and chines the same way the garboard overlaps the chine on the sides.

[jalmberg]

What 'gap'? The bottom overlaps the lower edges of the garboards and chines the same way the garboard overlaps the chine on the sides.

Got it. So the bottom overlaps the bottom of the garboards, instead of the garboards overlapping the sides of the bottom. Simple.

Thanks: John

[Bob Cleek]

Get a copy of "Building the Herreshoff Dinghy" from the WB Store. It's a little paperback that gives a step by step practicum for building a clinker dinghy the way the did it at Herresoff's. It describes the process in detail. What you do is nail the planking with the boat on a form upside down (Except for the nails through the frames, half of which are bent over the molds), then (leaving the forms in the boat, but removed from the "ladder") turn the boat right side up and attach roves and rivet them up. Then bend intermediate frames in place into the boat and rivet. Then remove molds and rivet remaining frames.

On soft wood, the rivets should pretty much countersink themselves. You can use a holder that springs a curve in a file (pictured in the book and still sold by some specialty tool catalogs) and use that to file off any copper head edges that remain standing proud.

[Doug Hamilton]

Here is one such tool.

www.leevalley.com/wood/page.aspx?c-2&cat=1,4254,56530&p=56530 (http://www.leevalley.com/wood/page.aspx?c-2&cat=1,4254,56530&p=56530)

How often would you use it?

[jalmberg]

On soft wood, the rivets should pretty much countersink themselves. You can use a holder that springs a curve in a file (pictured in the book and still sold by some specialty tool catalogs) and use that to file off any copper head edges that remain standing proud.

Several people have said that the nails don't need to be countersunk, but I used copper nails on another, non-boat project, and after a couple years, the nails discolored the paint... nothing dramatic, but you could see where each nail head was.

I'd like to avoid that, which is why I was thinking about countersinking/plugging them. Is that overkill? Should I just use some sort of primer that would prevent this discoloration?

-- John

[dmede]

Several people have said that the nails don't need to be countersunk, but I used copper nails on another, non-boat project, and after a couple years, the nails discolored the paint... nothing dramatic, but you could see where each nail head was.

I'd like to avoid that, which is why I was thinking about countersinking/plugging them. Is that overkill? Should I just use some sort of primer that would prevent this discoloration?

-- John

Its not that they don't need to be sunk under the wood and covered with a bit of filler, its that you don't need to pre drill for the counter sinks. Cedar is soft enough that with the right tools you will be able to sink the nail heads 1/8" into the wood and fill them before painting.

[jalmberg]

Its not that they don't need to be sunk under the wood and covered with a bit of filler, its that you don't need to pre drill for the counter sinks. Cedar is soft enough that with the right tools you will be able to sink the nail heads 1/8" into the wood and fill them before painting.

Okay, I get it now. Thanks. Lots to learn...

[jalmberg]

Get a copy of "Building the Herreshoff Dinghy" from the WB Store. It's a little paperback that gives a step by step practicum for building a clinker dinghy the way the did it at Herresoff's.

Just requested this through the library. Thanks for the tip.

[holzbt]

http://www.woodenboat.com/forum/showthread.php?t=8645&highlight=new+boat+a+building

Hi John,

Read through this thread. It's a photo essay of the building of a 14' flat bottom skiff. Although it's not lap sides, and with a slightly different building jig setup, there are many similarities to the building methods that will be required for CABIN BOY. If you can, search DMEDE's threads from the building of his boat. I think you will find them very helpful also.

[floatingkiwi]

If I countersunk the timber where I have replaced fasteners on the Folkboat, I would fear the fasteners might pull through the already quite thin planking in that area.

[Mrleft8]

That's a thought... if the nails held good enough to hold the planks together until the boat is removed from the forms, then rivet right side up. Perhaps clench a few so the planks don't separate. Interesting idea. Thanks!

If you predrill the pilot holes about 2-3 drill sizes smaller than the diameter of the nail it should hold just fine. Another point is to get nails that are just a little longer than your planking/frames are thick. Mine were 3" long, but the planking.frames were only an inch total. So the inside of the hull looked something like an inside out porcupine, or some Draconian torture device. This made pulling it off the mold more difficult as well as being a waste of copper.

[jalmberg]

http://www.woodenboat.com/forum/showthread.php?t=8645&highlight=new+boat+a+building

Hi John,

Read through this thread. It's a photo essay of the building of a 14' flat bottom skiff. Although it's not lap sides, and with a slightly different building jig setup, there are many similarities to the building methods that will be required for CABIN BOY. If you can, search DMEDE's threads from the building of his boat. I think you will find them very helpful also.

Wow, that is helpful. One thing I learned just from looking at your pics... the book I have shows the planks being put on from stern to stem. I have been wondering how I am going to be able cut the plank perfectly so that it fits into the stem rabbet. Much simpler when you *start* at the rabbet and work towards the stern, leaving some wood hanging off the back that can be trimmed flush with the transom.

I'm starting to think that the guy who wrote this book liked to do things the hard way. ;)

Thanks: John

[holzbt]

I don't have Kuhlig's book in front of me but I have read it. I recall thinking that he did a nice job on the boat and obviously had woodworking experience but that he was definitely not a boatbuilder. He did more than a few things that an experienced boatbuilder would never do.

[Paul Kessinger]

I just riveted up an Auk dinghy using the Cleek/Herreshoff method -- nail it all together, flip and peen over roves.

I used square "rose head" nails that were really tenacious. They really squish the wood fibers in around them and seem to make a little indentation in the roves where the circle meets the square and held the roves on super-tight, too.

Rose heads are meant to sit above the surface a bit and become a feature of the finished design. Nice on a bright-finished boat, but for paint I'm not sure they'd look too great.

But I'd really recommend the square nails I got online from Faering Design, round or rose head.

PK

[dmede]

Wow, that is helpful. One thing I learned just from looking at your pics... the book I have shows the planks being put on from stern to stem. I have been wondering how I am going to be able cut the plank perfectly so that it fits into the stem rabbet. Much simpler when you *start* at the rabbet and work towards the stern, leaving some wood hanging off the back that can be trimmed flush with the transom.

I'm starting to think that the guy who wrote this book liked to do things the hard way. ;)

Thanks: John

That method works for small boats with single plank (or built up single plank sides), not really appropriate for lapstrake planking.

For your boat after getting a rough-cut plank you will be clamping the plank amid ship on the center building frame and working alternately front and back to slowly clamp it in along the length of the building jig. You will leave both ends long and only the aft portion will pull all the way into the transom, the end at the stem will probably be too stiff to pull in all the way without breaking the plank so leave it off the stem.

Mark for any extra fitting you may need to do with a hand plane, then mark the rough shape of the stem up front (mark directly or use a template). Pull the marked plank, plane to fit and cut the stem end. Reposition on the boat and steam the stem or hood end of the plank so that it will be soft enough to pull into the stem. Once it's cooled and set you will be able to pull the hood end in all the way to the stem rabbet, it won't fit right but thats ok. You re-mark and re-fit until it's just right. As you re-fit the stem end you are pulling the plank slightly forward which is ok because you left the aft end long. If done correctly you may end up pulling the plank forward as much as 1/2" to 1" with no real effect in plank landings or shape.

That’s how I did Ollalie anyway and I may have omitted some steps but it's more or less correct and will likely be the best way to go about your build. There are a number of books out there with good info on building boats but I found most of them did not give much in the way of flat bottom lapstrake skiff specifics. You’ll need to gather all the info you can and be your own editor, taking bits and pieces of building wisdom from various sources. Be especially wary of applying round bottom lapstreak techniques to a flat bottom lap skiff. ie "Building the Herreshoff Dinghy". A lotof what's in John Gardners books is more appropriate to an Atkins skiff build. I also used "Boatbuilding" by Chapelle, "Building Small Boats" by Rossell and "Lofting" by Vaitses.

dave