Pirates Chest - construction techniques?

[George Matthews]

My grandson will be visiting for a few weeks soon, and I had in mind to build him a 'Pirates chest'. He chose the one in the photo, and it looks like a challenge. I have build many pieces of furniture, but the chest looks more like boat building. I never use plans, just design from scratch. So I searched the web, and the creek, found a few old threads, but nothing specific about the techniques used to construct the chest.

Can anyone offer some details?

[Dave Richards]

You're right. It looks a bit like boat building techniques would apply. I think for the top I would build a strongback similar to that used in boat building with maybe three molds and the lid ends. I would figure out how many planks and line off the molds accordingly. First install a layer of planking to make a smooth rounded top. The planks would be edge butted.

The black straps are probably iron although you might make a substitute. Then a another run of planks staggered with gaps.


The planks could probably be in the neighborhood of 3/16" thick. You'll have an amazing amount of strength when all the planks are installed and fastened together.

Bronze holdfast nails at the ends into the end pieces and epoxy to glue the seams.

I could help you with coming up with plank shapes if you want.

[George Matthews]

The black straps are probably iron although you might make a substitute. Then a another run of planks staggered with gaps.

The straps look like mild steel, and since I 'grew up' in a machine shop, have no difficulty making those. It looks like the straps are fastened over the first layer and then, as you helped point out, another layer added to cover the joints.

Do you advise 'cinching' the straps, and or the board edges with copper nails?

Thanks for the quick response!

[Dave Richards]

I guess if I was doing it, I'd use copper rivets and roves because the planks would be pretty thin. I'd be afraid of the point of the nail coming back through the top surface if you were clinching them.

[George Matthews]

I guess if I was doing it, I'd use copper rivets and roves because the planks would be pretty thin. I'd be afraid of the point of the nail coming back through the top surface if you were clinching them.

Any site you can point me to that can provide a 'land lubber' with the tips-n-techniques of selecting and using rivets and roves?

[Dave Richards]

George, you can get the the copper rivets and roves from Jamestown Distributors or WoodenBoat.ORG (notCOM) Chandlery. Or here: http://www.faeringdesigninc.com/
Here's instructions for setting them. http://www.faeringdesigninc.com/instruct.html

They're pretty easy to do. I use a tiny ball peen hammer and a large bolt with a hole drilled in the end (threaded end) as a rove set. A small maul makes a good bucking iron. I took fine sandpaper to the faces of the hammers and polished them up a bit. Just predrill the holes with a drill the same size as the flat side of the nail (they're square) and make sure to back the planks along side the hole when starting the nail through the hole.

You can hear a change in the pitch when setting the rove that lets you know you're done.

I don't think you'll need bigger than 12ga. rivets.

I used 14ga on the cradle boat I made for my son.

[Dave Richards]

By the way, thread as many nuts as you can on the large bolt (I think I used a 5/8" bolt) and wrap it with friction tape to give yourself something to hold on and to give the rove set a bit of mass. Teach your grandson how to hold the bucking iron. Bucking rivets on something like this is considerably better than bucking rivets in the tail of an airplane.

[Michael Ballent]

Good night, that looks like it would take a whole lot more skill than I have... You have to post some pics once you are done. The top looks like a slice off the top of a football, curved across both X and Y axis. YIKES. Definitely a challenging project. Can't wait to see this when its done

[Jerry Todd]

George,
I would like to follow your progress. How about some "in progress" photos?
Looks interesting.

[George Matthews]

George,
I would like to follow your progress. How about some "in progress" photos?
Looks interesting.

Will do Jerry.

Thanks for all the detailed help Dave.

[Dave Richards]

you're welcome.

Thought I'd post a description of how I'd attack the lid. I'd cut the end pieces slightly oversized along the top edge since it should get a bevel along there. The inside face will be larger than the outside. Set the ends up with a a cross piece (the strongback) between them in the form of an H. Set up three molds which are the shape of the inside curve at regular intervals between the ends. You could even put on the front and back pieces to make things more rigid. Just remember that the molds and strongback have to come out at some point.

Fair the curves and work in the bevels using a batten bent over the molds and ends. Use a block plane to work the material down so the batten will lie down over all 5 pieces.

Decide how many planks you'll need to get out to cover the top. The narrower they are the more easily they'll bend to fit. But the curve is pretty shallow and so you won't need to cut the planks too narrow. Evenly divide each end and each mold and mark for the location of the seams. Also mark the center of the molds and ends.

I'd start by laying down the center plank first. Let the planks run long. they can be trimmed to length after installing the last one. Clamp the piece in place and make marks on the underside at each end and at the molds. remove the plank and connect the marks by bending a batten to intersect the marks. Cut and plane to the line. Install the plank with bronze ringnails into the ends. Leaving the planks long gives you something to hold onto and prevents the plank from splitting.

Clamp the next plank in place overlapping the first. You can trace the edge of the first plank to get one side. Mark the other side as before and cut and plane until it fits. Look down the length of the plank edges to make sure the curves are fair.

This should actually be easier than planking a boat because you don't have to plane bevels or gains on the planks.

A quick Google yielded this image of a model of a pram. On the left is the strongback. For the trunk lid though, the 'transoms" will be vertical and the first and third mold will be mirror images of each other.


Michael, I'm sure you could do this. You definitely have the talent.

[George Matthews]

George, you can get the the copper rivets and roves from Jamestown Distributors or WoodenBoat.ORG (notCOM) Chandlery. Or here: http://www.faeringdesigninc.com/
Here's instructions for setting them. http://www.faeringdesigninc.com/instruct.html

I also found a Canadian source at Lee Valley...
http://www.leevalley.com/hardware/pa...=3,41306,41324

[Dave Richards]

Yeah, I think rose head nails would look nice on a chest like that. Good luck.

[George Matthews]

Dave
What do you recommend for the top layout... A, B, C or ?

[Dave Richards]

George, I think version C is the right way to do it. After putting down the first layer of planks, layout the locations for the second layer and fit them. Don't install them though. Add the iron straps, then mark the second layer of planks so you can cut the dados for the straps. Then install those planks.