I assembled the panels of the scow using a combination of a building jig and the 'stitching' method.

The building jig (see this page) was used to hold the panels in approximately the correct place - the major advantage of this was that I could mostly assemble the scow single-handed (I built the scow in our factory out of working hours, so I was usually on my own).

1. Assemble the individual panels themselves - for example, fit the seat bearers to the four seat/tank bulkheads, join the fore and aft parts of the side panels, etc.
2. Make a sub-assembly of the forward seat/tank bulkhead (the one at the aft end of the forward seat/tank), the mast step and the centreline bulkhead inside the tank. You can 'glue' these pieces together with an epoxy resin/microfibre mix and fillet them later (in step 16).
3. Put the three plain seat/tank bulkheads in position on the jig and use one small screw into each upright of the jig to hold them in place.
4. Fit the bulkhead/mast-step/centreline-bulkhead sub-assembly to the jig. Screw the bulkhead to the uprights of the jig as before and rig up a temporary cross-brace to support the front of the centreline bulkhead - once the bow transom is fitted, this support isn't needed.
5. Fit the fore and aft transoms to the jig. This needs a bit of care to line up the seat bearers with the top of the jig longitudinals. The angle of these transoms is not too important, as they will be held at the right angle when the sides are fitted. Use two small screws to fix the each transom in place, one into the end of each longitudinal of the jig.
6. Lift the two side panels into place and temporarily tie them in place with a bit of string. The position of each bulkhead should have been marked BEFORE the panel is fitted. Fix the side panels to the bulkheads, starting with the two bulkheads of the centre seat/tank. I used two copper wires to secure each joint, one near the top and one near the bottom - drill two holes in the side panel (one in front of, and one behind, the bulkhead) and drill one hole in the bulkhead in line with the side panel holes. Pass a piece of copper wire (I used 2.5mm2 wire from 30amp UK cable for wiring power outlets) through the three holes and twist the ends lightly together - this is just a trial fitting. See the diagram below.



7. Try putting the bottom panel in place, just to check it is the right size, etc, but do not trial fit it yet.
8. Make up enough epoxy 'glue' to do the joints on ONE side panel (don't try to do both at once). To assemble the components, you made a 'glue' consisting of epoxy resin and microfibres, which can be a bit sloppy (or viscous) for this job, so make the 'glue' mix stiffer (less viscous) by adding a little silica. As well as making the 'glue' stiffer, the silica will make it much harder when it is cured, so clean up joints as you go and do NOT assume you can sand 'blobs' off later - the 'glue' will have set like rock!
9. Remove the side panels, coat each joint surface on the bulkheads and transoms of one side with the epoxy 'glue' and refit the side panels, twisting the copper wire ends together lightly. Check the fit of all joints and, when they are all in line, tighten all the copper wires to pull the joints together. Unlike normal household adhesives, an epoxy 'glue' made by you does not need to have the joints pulled together as tightly as possible - indeed some wood/epoxy boatbuilders believe you should not "squeeze joints dry".
10. Repeat steps 7 and 8 for the second side panel immediately - you are much more likely to get both sides symmetrical if you assemble them at the same time.
11. After the joints in the sides have cured, trial fit the bottom panel. I had the luxury of using lots of 8kg lead weights from the factory, so I only had to use copper wire joints at the bow, where the weights would slide down the slope of the bottom. If you do not have access to lots of weights (and you probably have - for example, house bricks would be ideal), you will need to wire each joint - maybe three wires for each bulkhead or transom joint and wires every 300mm (12") along the side joints.
12. Fit the bottom panel using the same 'glue' as for the sides. You MUST have a helper to position the bottom panel as otherwise when you make small adjustments to its position, you will 'wipe' the glue off the bulkheads and sides.
13. When the bottom joints have cured, turn over the hull with the jig still inside it. The 'glue' joints are surprisingly strong on their own, but you stand a better chance of not breaking them if you leave the jig in place as long as possible.
14. You now need to 'fillet' all the joints. For this you will make up a fairly stiff epoxy 'glue' mix - I found that equal proportions of microfibres, silica and lightweight filler made a good filleting mix: the cured mix is strong, but the lightweight filler makes it soft enough to be sanded - if you used only microfibres and silica, the cured mix is like rock and can only be 'sanded' with an angle grinder!
15. If I built the scow again, I would also add graphite powder (SP Systems sells it) to colour the fillets black - my pure white fillets looked gorgeous when the scow was new, but have discoloured yellow in sunlight (despite being coated with a varnish that is supposed to contain UV filters to prevent this). Most professional wood/epoxy boatbuilders use a brown colouring agent to try to make the fillets invisible, but I personally don't like this.
16. Start by filleting the joints inside the seats/tanks - these first attempts won't be seen when the boat is finished, so you can get some practice before doing joints that will be seen. Use a normal lollipop stick (or, for the medical amongst you, a tongue depressor) to form the radius in the corners - the fillets should reach at least 12mm (1/2") on either side of the joint. Epoxy suppliers generally sell lollipop sticks/tongue depressors for this purpose.
17. Now fillet the joints inside the fore and aft 'footwells' between the seats/tanks. Because of the size of the unsupported bottom panels in these footwells, I used larger fillets to join the bottom to the sides which could not be formed with a lollipop stick/tongue depressor, so had to make larger versions to use as a filleting stick. I tried to achieve about 20mm (3/4") 'leg length' on these fillets and they haven't broken yet. Regular-size fillets are fine for the side-to-bulkhead joints in these footwells.
18. With all the fillets in place, the jig can be dismantled and removed in pieces. Continue to support the hull at about one-quarter of its length from each end (to prevent longitudinal bending) and make sure the two supports are EXACTLY level with each other, otherwise you will build in a twist in the hull - this is VERY important while you are fitting the seat/tank tops.
19. Fit the 'shear doublers' as shown in the page titled 'Leeboard Pivots' here.
20. Fit small 9 ply doublers just inside the bow and stern seats/tanks, where the side rubbing strakes on the bottom will end.
21. Turn the boat the wrong way up to fit some bits to the outside of the hull before sealing up the tanks.
22. Fit the centreline rubbing strake to the hull bottom - I built mine up from two layers of 22x10 (1"x1/2") mahogany as the bends are quite tight to get a one-piece strip around. Fix each layer with an epoxy/microfibre 'glue' and short brass screws driven out from inside the boat.
23. Fit the two side rubbing strakes to the hull bottom, as in step 23. I suspect there is a lot of resistance from these strakes, so if you are not intending to bash the sea bottom much, you could leave them out. BUT if you do, you need to put back the strength they provide to the bottom panel by fitting them inside - in which case fitting two or three across the bottom (tranversely) would be easier and would give your feet something to grip when rowing.
24. Fit the leeboard rubbing strip to each side, using an epoxy/microfibre 'glue' and short brass screws driven out from inside the boat.
25. Turn the boat the right way up and check the supports are level.
26. Fit the skeg doubler to the bottom panel inside the aft seat/tank. You won't be able to get at the inside of this tank once the top is fitted (yes, that's obvious, but it is nevertheless something that can be forgotten!), so fit the seat bearers to the side panels first. They need to be held into the curve of the side panel while the 'glue' cures: you can either do this with lots of clamps, or use a couple of clamps and work your way along the panel using brass nails from the outside (which I think look quite nice when left visible).
27. Before you seal up any of the seat/tanks by fitting the tops, coat all the inside surfaces with a generous coat of straight epoxy resin - this will prevent any deterioration or rot if the tanks should leak.
28. Fit the top of the aft seat/tank. Most of the joints are square, so an epoxy/microfibre 'glue' is sufficient, but you really need a filleting mix to make the joint between the top panel and the aft transom (unless you squared off this joint when you were filleting inside the seat/tank, in which case you need to sand the surface to get a good bond).
29. Fit the horizontal top of the mid seat/tank. Then make up and fit bearers to support the sloping ends on the top of the two bulkheads, and fit a third bearer to the shear doubler. Fit the sloping ends of the seat/tank top using a thick filleting mix underneath the inboard end - this will 'squish' to form a triangular fillet that will join the sloping ends to the main top panel.
30. Fit bearers to the side panels of the bow seat/tank and then fit the top. This needs to be trial fitted carefully so that it has a hole that is a neat fit around the mast step which sticks up through the seat/tank top.
31. Once the three seat/tank tops are fitted, the boat will be much, much stiffer in torsion than it was before. But continue to support it carefully on level supports until these panels have been filleted in place.
32. Use regular-sized fillets around the top of each seat/tank to connect them to the side panels and bow/stern transoms. The joints between the seat/tank tops and their respective bulkheads rely on just the internal joint of the seat bearer - but if you want to build strong, you could add some light 50mm (2") wide glass tape over these joints.
33. Build up a big fillet around the mast step to make it really strong (see photo of finished mast step here).
34. Fit the 'inwhale' (or 'sheer clamp' in the US) to the inside of the top of the side panels. You will need to cut away part of this piece so that it fits over the shear doubler. Fix in place using an epoxy/microfibre 'glue' with brass screws driven in from the outside of the side panels.
35. Fit the 'gunwhale' or rubbing strake to the outside of the top of the side panels, using epoxy/microfibre 'glue' and longer brass screws driven out from the inside, through the inwhale and the side panel into the gunwhale.
36. A rubbing strake can be fitted across the top of the bow transom - it isn't needed for strength, but it does work as a spray deflector if the bow transom is 'stuffed' into a wave.
37. Fit some assorted reinforcing panels inside the boat - I used some solid mahogany which looks lovely, but thick plywood would be at least as strong. The reinforcing panels are:
    a) a doubler on the back of the bow transom if you are going to fit an eyebolt to which to tie a painter - a doubler with a hole through it and a big knot in the painter would be cheaper;
    b) a 6 or 9 ply doubler can be fitted to the centre of the bow seat/tank bulkhead - with the internal doubler that is part of the mast step, this makes this 18mm (3/4") thick which will allow screws to hold the various cleats to this panel;
    c) two doublers each side for the leeboard pivots (see 'Leeboard Pivots');
    d) a doubler each side behind the mid seat/tank to which to screw the leeboard jam cleat (see this photo);
    e) blocks at the aft end of the shear doubler to mount the rowlocks on;
    f) a doubler on the transom to make it the right thickness for the clamp of an outboard motor (if you want to use one).
38. Fit the external doublers for the leeboard pivots (see 'Leeboard Pivots').
39. Drill the two holes in the transom for the mainsheet bridle (see photo here).
40. For the best protection, turn the boat over and apply light 50mm (2") wide glass tape over the external joints on the outside of the hull. This isn't really needed for strength, but will protect these vulnerable corners well. Be sure to allow any exposed end-grain of plywood to really soak up resin with at least two applications of straight resin before applying the tapes - otherwise the end-grain will 'suck' resin from the tape.

• an eyebolt through the bow transom to tie the boat's painter to;
• metal capping ("keel banding") on the rubbing strake(s) under the hull;
• the leeboard fittings (see 'Leeboards');
• a bit more keel band on the top of the gunwhale to take the impact of the leeboard stop pin (see photo here);
• oars and rowlocks;
• small eyes on either side of the bow seat/tank bulkhead with shock cords and hooks - to tie the oars into the scow when sailing and to stop them being lost overboard in a capsize;
• rudder pintles and gudgeons;
• drain holes and plugs in the three tanks - during building I decided that the centreline bulkhead in the bow tank was such an obstruction to draining any water from the tank that I made it continuous and so I have two bow tanks, port and starboard;
• a natty little nameplate to allow others to know the name of your finest handiwork - I was delighted to find that a inkjet-printed piece of paper can be stuck to the hull when coating it with epoxy resin - the ink doesn't seem to bleed.

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