some ideas

-from reading others, for basic shape some use long pc of fat solder or lead and wrap around the yak half and carefully remove and trace form, if you're careful it'll form and retain its shape. i therefore would imagine that heavy copper wire may be a poorer but useable substitute. try that hvy 3line housewire.

-pure guess, but i wonder if spray foam w/ some scrap added may be workable and quick. make sure yak is masked. turn yak on side, mark every ft, mask, lay on 1in wide scrap cotton open cloth, line of sprayfoam, move on to next, or maybe scrap of open rag cloth on top too. prob the quickest.(all of these for half forms only). best is prob, litght foam, cloth, light foam, get exact profile.

-3/for my purposes i want to know the alignment but don't have time to set up horizontals and worry if the yak is bumped etc. So if you actually just make sure you have the beam measurement at ea location(i would always measure it separately as it is so important and is a good double check) all you need is an UNaligned string anywhere in ANY orientation as a means to keep the forms in . for simplicity if the bow and stern are tall, is to run a line connecting both of their peaks, if not just a stick extension on one(verticality is not important) so that a straight line is achieved. this approach assumes that a deck or hull ctrline is obvious. or if not, make sure the yak is at least level across ways

-for bow and stern shapes, if at night shine a flashlt from some distance against a wal and draw from lthe side. or put yak on its side and use a plumbob around the shape and mark the dots on paper on floor, gets an exact shape, then.

-for form takeoff, in next cases need a vertical surface of some kind to draw or clampagainst, best idea is just screw one to the end of a sawhors and assy along yak to next 'station'

- one method would be to have 2 stiff card of light ply 'L's say 8"x14"by w/ each 'L' say 5in. overlap clamp them to make a sideways U shape tight against the yak. dwg paper previously attached to ea 'L'. make a circle of stiff card or 1/8 ply say 6in in diam, small better, and drill a ctr hole justlarge enough for pencil point. roll around the yak and get perfect normal 3in offset. draw line where the 2 legs meet and move to next form. maybe remove get new paper, prob could could put paper on back and flipe every 2nd form and do all on 2 sets of paper for quickness.

-if you ahve access to a drafting parallel rule, set up vertically beside and use a 2ft 'yardstick' pointy on one side, matching hole on other and just trace the outline. might have to offset the point if dips and valleys

-or one of thos e old drafting arm machines would be the absolute quickest. same action as above

- or make your own real easy. would probably hold up for a bunch.
attach vertical bd say 18x18 to side of swhorse. make 2 identical 9-10" arms at ea top corner(say 1/8ply), attach to yardstick below same spaceing. will make exact tracing.

- make sure you put a dot/tick on ea formset takeoff where the stringline is

mick