I'm starting an Oxford Wherry build from plans. I have not worked from full size plans before. I have printed the plans and wondering how to most accurately transfer the drawing to the plywood. The instruction book says to see the instructions that came with the plans, but I cannot find. Any advise is appreciated.
Hello Austin,
It looks like we accidentally didn't include the addendum outlining the tranfer process. Apologies for that. I will include those directions right here:
Instructions for Working with Full-Sized Hull Panel Plans
Instructions below refer to the Expedition Rowboat, however, the same basic techniques for cutting out hull panels for all models. Refer to plans pages for panel layout and thickness of plywood for your specific model.
The full-sized plans offer a quick and accurate way to transfer the panel shapes onto the plywood blanks. Time required to trace and cut the Expedition hull panels is 1-2 days (not including joining the panels).
Readying the Blanks: Prior to scribing the panel shapes, it is necessary to cut and join the plywood sheets to the rough required sizes. It is easier working with the plywood if it is cut to the approximate required widths prior to joining. For the two bilge panels the blanks should be 15” wide, and 9” wide for the two sheer panels. The panel lengths should be 18.5’ in total, made from two full eight-foot sheets and one 2.5’ piece.
The side panels are cut from 4 mm plywood and the bottom panel is from 6 mm stock (refer to plans for blank dimensions for bottom panel).
Refer to page 13 in the manual for instructions on joining the panels. The manual gives directions for joining whole plywood sheets, but the principles are the same for smaller-width blanks.
Transferring the Shapes: Unlike smaller templates, it is not recommended to cut out the panel shapes to trace. Due to the long narrow shape of the panels, paper cut to this width. Instead, just cut a rough line approximately half way between each panel. This leaves adequate width to prevent any distortion when the paper is laid flat.
Lay each paper panel over the corresponding blank, making sure the full panel shape is backed by wood. Place a weight in the middle, and carefully smooth the paper out towards the ends with your hands, making sure the paper sits completely flat. Place several more weights along the paper’s length so it cannot shift.
Using a hammer and nail, lightly tap a mark every three inches along the edges of the panel. Be sure that you are marking along the outer edge of the black lines.
After marking the full perimeter of the panel, remove the paper and connect the dots using a ruler and pencil. The proximity of the dots means that a batten is not required to create a curve, as any deviation from a continuous curve is negligible.
For the tighter curves at the ends of the bilge panel, these are created by precisely cutting and tracing the shapes from the template after the overall panel shape has been created. The curve at the end of the bilge panels is slightly different to the templates illustrated in the smaller plans. The full-size templates are the same as the original expedition boats, however, we recommend using the slightly larger diameter curve found on the small scale plans. Either, however, work equally well.
Important: When scribing the bottom panel, be sure not to reverse the mirror image. The template provided is only one half of a full panel and it is necessary to use it to mark both sides.. Transcribe the first half as described above. To mark the second half, turn the template upside down and place precisely next to the half already marked. Be sure to mark to the very perimeter tips of the template. These extremity points correspond with the centre of the bottom panel. The nail perforations in the template created when marking the first half can be used as guides to tap your nails.
Cutting out the panels: The bilge panels and sheer panels can be cut out two at a time (as described in manual), however with templates, it is actually faster marking and cutting the panels individually. After transcribing both bilge panels, sheer panels and bottom panel, place the panels one at a time on a work table (with overhanging ends supported on sawhorses or similar supports) and cut with a jigsaw or hand saw. A hand saw is surprisingly quick, and usually more accurate than a jig saw. Be sure to continually move the panel so the wood being cut is supported by the work table, with the cut point just out from the table’s edge. Cut as close to the outside of the pencil line as you feel comfortable. If you’re a little shaky with the saw, don’t worry about leaving a few mm of excess wood. It’s always better to err on the cautious side. You can easily shave off excess wood, but you can’t bring back wood mistakenly removed. After cutting out the rough panel shape, you can quickly and accurately shave off any excess using a block plane. (refer to manual for more detail).
Thanks, this is what I was going to do. I cut using a 4.5" battery powered skillsaw with the blade adjusted to cut 2x the wood thickness. It is easy to control & go around curves. Much, much better than a jig saw.
I retired last year and built 2 boats. This is my third.
Nice. Good to hear it's going well. Yes, I've heard of people getting good results with the smaller skillsaws. Sounds like the pinncale retirement project - creating an armada of boats for different conditions. Have fun with boat number 3!
