Framing at a Glance
Accomplished captain and shipwright Zeal from Washington describes his experience of working on the framing stage in this blog post, “Framing at a Glance”. Combining technical detail with elegant prose, this post is well worth reading.
I come from a place with a strong maritime tradition. In the late 1800’s Puget Sound, Washington, USA was scattered with wood mills, port towns, and shipyards. I am both a captain and shipwright by trade, and am following in the footsteps of the builders before me. Those who have mentored me, and those who have taught me through the shaped timbers they left behind. My journey is one of learning, to discover what is possible, and to help accomplish that which others might see as impossible.
Zeal Chimenti
Shipwright from Washington
After a break over the holidays, the team has assembled once again. The call of the chainsaw birds are loud throughout our jungle shipyard as many minds focus on the work at hand.
Week after week, month after month, the ship starts to fill the space set aside for her. She slowly reveals her form, as this dream turns into reality. There are many moving parts and teams of people to build just one frame, no one part any more necessary than the other. All these parts help keep that river of progress flowing without too many twists and snags. The teams in each process must take care to be thorough, otherwise any problems just flow down-river to the next stage. Here is a brief overview of what it takes to turn a tree into the frame of a ship.
Turning Timber into Lumber
Logs arrive in the round of varying lengths depending on what part of the ship they are destined to be a part of. Every piece on the ship is milled on site, in house. We use two varieties of trees for our frames, those being Guapinol (Latin: Hymenaea courbaril) and Cedro (Latin: Cedrela Odorata). The majority of the framing is constructed of Cedro. Guapinol being the denser species, we are using for strengthening key areas of the ship that are anticipated to be high stress areas, and every fourth to fifth frame section to add strength to the ships structure. Each log is inspected for its shape, and any defects that could be avoided during the milling process. This is when it is decided what this log will become, a keelson, deckbeam, rudder stock, bilge stringer, or frame section. The logs are cut to length, and moved the milling arena, where they are blocked in place to utilise the straightest side to make the first cut. Using nails and strings the dedicated sawyers carefully lay out a perfectly flat plane by driving nails into the log. With strings they sight the nails height, so the nail heads are all in precisely the same plane. Once the nail heads are in a satisfactory location, a plywood guide (or ladder for logs without much sweep) is set on top of the nail heads to use as a reference face for the Alaskan Chainsaw Mill. This first cut creates a flat and straight plane, with which all the rest of the cuts on this log will be referenced off of. The framing stock is rough sawn at nominal 6” thick, to make up half the thickness of Ceiba’s 12” frames. Like magic, from timber to lumber.
Lumber arriving at the shipyard
Milling Guapinol hardwoods
What shape is it anyways?
This is where we take a two dimensional image, and create something three dimensional. On the lofting floor the ship is drawn to full scale in three different views. Profile view (from the side), Half breaths (from the top/bottom), and Body Plan (from forward and aft). Only the starboard side of the ship is drawn, because the port side will be exactly identical. Using the body plan view, every frame on the ship is drawn, both the inboard and outboard face (also called the moulded section). A sheet of mylar (clear plastic) is layed out over the body plan view of the frame section, and the inboard and outboard faces are transferred from the lofting to the mylar. In the body plan only the starboard side of the frame is layed out, and can be flipped over to create the identical shape for the port side (thanks to the clear mylar). All the reference lines used to ‘prove out’ the shape of the lofting, those being the waterlines, buttlines, and diagonals are transferred onto the mylar. Using the frames forward, and aft of the frame section being transferred we can establish at what bevel (or angle) the frames will be cut. This information is established and recorded on the mylar. Once the shape of the frame, all the reference lines, and bevels are written on the mylar. Taking into consideration the shape of the frame and the framing stock milled, the location of the butts are established for each futtock section. The ‘futtocks’ being the various pieces that overlap and fasten to each other that make up an entire double sawn frame. All the information recorded is taken at the athwartships centerline of the frame, between the forward and aft futtock sections. This enables us to use only one pattern, and one set of bevels for both forward and aft futtock sections.
Using the tick stick on the lofting floor.
Measure Twice, Cut Once!
Using the mylar, the stock to be used for the various futtock sections that will make up the frame will be selected and put aside. The stock having been rough sawn to thickness with the Alaskan Chainsaw Mill, one face will then be perfectly flattened with a handheld power planer. This will account for any warping of the lumber after the initial milling so the faying surfaces of the futtock sections will fit together with no gaps. All of the bevels, and reference lines on the mylar are transferred to the flat face of the futtock stock. On the outboard face of the frame, an extra 5mm of material is added to the moulded dimension. This accounts for any inconsistencies in layout, and provides more material for fairing the frames before the hull planking is attached. Once all the information is laid out on the stock and double checked, the frames are cut with one of two tools. The lighter species of wood (Cedro) is staged, then cut to shape on the ships saw. The denser, heavier Guapinol frames are cut with a bevel jig set up for the chainsaw. Sometimes it is easier to move the stock to the tool, other times with such heavy pieces it is easier to move the tool to the stock.
Are you sure that's the right spot?
As soon as the futtocks are cut they are moved on to the framing stage. The shape of every frame is unique and different. To establish the exact location of each futtock we use what is called a ‘tick stick’. Made from a 2” x 4” rectangular steel tube section. In the body plan view, we record locations on the tick stick. Measurements are taken from a known reference point on the ships centerline, to where the waterlines, diagonals, and buttlines intersect the outboard face of the frame. At each waterline we record half breadth measurements (widths) from the centerline of the ship. Diagonal measurements are also taken from W1 (waterline one) at the centerline, to the location where the waterlines intersect with the outboard face of the frame.
With this myriad of information, we begin to assemble the aft face of the frame. Starting with the floor timber, which is the frame section that attaches to the keel timber. The notch for the keel is cut, then the floor timber is blocked and leveled. Working up towards the sheer on both sides the futtocks are blocked up, leveled, the ends cut, fit, and tarred. All the reference points are checked, and double checked to be certain the futtocks are being assembled in the correct locations. Once the aft futtocks are assembled to satisfaction, all the reference lines are transferred to the sides of the frames. The forward futtocks are then placed on top of the assembled aft section. The forward futtocks are matched with their counterparts, the ends cut, fit, and clamped into place.
Costa Rican shipwright Marvin working on a frame piece
Now that all of the futtock sections are assembled and dry fit, they will be pre-drilled for both trunnels (1 ⅛”) and bolts (⅞”). The futtock butts are all bolted and trunnels fasteners are placed between the butts to fasten the forward and aft frame sections together. The holes being drilled, the forward futtock sections are then disassembled, coaxes are installed at specific locations between the two futtock sections. Everything is then tarred for the final assembly, all the bolts and trunnels are installed, and the frame is now one contiguous unit!
On the Up and Up!
The entire frame being fully assembled, a cross spall is fastened from frame head to frame head. This wooden member ties the two frame heads together at the correct width. On the cross spall the centerline is established. It is then ready to be pulled out toward the ship. The frame is then moved into position by a gas powered winch. Hauling lines and stabilizing guys are rigged, to facilitate the frame raising. The keel notch is tarred and the frame is set on top of the keel. Working together in two primary hauling teams, one for each side, the frame takes her place standing proud amongst her sisters. Guy lines are tied down to temporarily hold the frame in place until the horning process is complete.
Putting Them in their Place
Once vertical, we must verify that the frame is perpendicular to the ship's longitudinal centerline, level athwartships (side to side), and plumb. This process is called ‘horning’ a frame. Only every fourth frame is horned, and the intermediate frames are referenced off of the horned ones. First the frame is leveled athwartships, a plumb bob is rigged from the centerline marked on the cross spall. The ship's longitudinal centerline string is set up, and wooden posts or shores are placed beneath the frame and hold it in place once the plumb bob is aligned with the centerline string. Next a point is established in the centerline of the ship roughly the distance of the beam of the ship aft of the frame station. Measurements are taken from this point at the turn of the bilge to verify that the frame is perpendicular to the keel of the ship. Hold downs are nailed to an already installed frame near the turn of the bilge, to hold the new frame in its perpendicular position. Plumb bobs on both outboard centerlines, port and starboard, are nailed at the top of the frame heads. Using the plumb bob, and the human eye, we align the frame to make sure the frame is standing perfectly vertical. Hold downs are then nailed to the next closest frame at the frame head. To prove out the frame is sitting as it should be, we pull diagonals from the inboard face of the frame head. Taking measurements to the same point established when initially squaring the frame to the ships centerline. This will verify that the frame is both plumb and square to the centerline at the frame head. If all the measurements prove out and the way the frame sits looks pleasing to the eye, it’s off to the next!! Then this frame sits along with the others, patiently awaiting the ribbands, stringers, beam shelf, and planking to make their appearance in the coming months.
Time moves in an odd way here, six weeks have passed since my hands first opened the blue iron gate leading to this place. I feel both as if I just arrived, and have been here for quite some time. In my life I have held much value in being connected to something greater than myself. A tradition, a culture, an ideology, a community. Over thirty pairs of hands, that is thirty minds focusing their efforts on one goal, the ship Ceiba. Envisioning the day when she will touch salt water for the first time, and take flight for that far horizon. In the shipyard there are many people from many walks of life, sharing a way of life. Differing ages and experiences, a variety of knowledge from opposite corners of the earth. These people bring many methods and ideas of accomplishing tasks in the most efficient and long lasting way. With all the challenges and limitations of building not only a ship, but also a shipyard. Building a community, being a part of this system of people who care about what they do.
I am grateful to be here.
