Making a bit of a start on my stretched Stiletto (more a Stilapier) at the moment, as it had been put aside while I had a play with a surface drive to fit to it, if I could get one working (see under surface drive experiment, in forum). I've shelved that idea till I can find a suitable universal for it, and have decided to use a modified cable drive instead (see under 'converting a cable drive to a standard drive', in forum) I wanted to settle on the drive type before starting fully, to make installation easier.

The Stiletto has been stretched to 38 1/2" by blowing the A4 sized drawings up to AO paper size. I've left out the usual internal locking structure so as to create more room and ease of access to the internals, instead, the whole cabin will lift off, rather than a few 'lids'. All the new positions have been worked out using top and bottom datum lines (pic 1). The deck camber has been changed but the deck sheer left in. A few other mods will be made as things progress.

I started by cutting out the keel, breast hook and new ply bulkheads, then cut the centers out of the bulkheads notched them for the stringers and reinforced them. I made a new universal building jig (under model framing jig, in forum) to hold everything in place, (right side up and upside down), and set everything up on it. Glued all the bulkheads bar the transom to the keel, (keel has shaft tube slot previously built in by cutting the keel on the appropriate angle, separating the 2 pieces by a shaft tube diam, trenching 2 side plates to suit the shaft tube angle and diam, and gluing/clamping them on using the building jig to hold them flat and straight.

I've made a cut-out for the motor in bulkhead 3, and bent the cable drive to suit. A motor mounting plate will be made later. Cable drive will have a V brace made to suit once the angle has been sorted for prop clearance etc.

Getting hard to find some modelling supplies (namely spruce strips for stringers and balsa) now so there might be some slow patches in the building.

The basic frame (keel and bulkheads) now flipped over, lined up on the jig again, with the necessary bulkheads packed for the deck sheer to keep it all in shape. The bulkheads are clamped to the jig to keep it all solid. Started fitting the bottom stringers, which once planked will make the hull easier to work on while fitting certain internals. Side and gunwale stringers will be done once any internal work (motor, shaft, rudder, floors etc) is done.

The hull has been re designed, as balsa planks and f/glass will be used, rather than ply, making it lighter but needing stringers all round. The original only had chine and gunwale stringers, (the ply replacing the intermediate stringers.) Also, the cabin construction was part of the framing.

Chine stringers now glued in place. Will possibly have balsa top laminations for finishing if needed. I usually leave the stringer notches a bit larger in places to allow for 'flow' alignment. Usually get a few waves in the stringers when re-modelling a hull, (even doing them from a plan) I just pack the gaps later with balsa glued in and trimmed.

You can run the stringers over the frames/bulkheads which will allow water to drain easier (no need for limbers) - runs straight to the transom from anywhere. Good method for open boats with frames, which will be subjected to water inside, as you can leave floorboards in and just tip the boat up to drain. Notching stringers is a probably a bit easier for models, as they don't usually get any water ingress.

I've finished the framing for now, and have started the planking. Started by gluing a 3mmx3mm spruce strip down the center of the keel, to form the 'rebate' for the 2.5mm balsa planking. Next thing was to cut the 100mm wide balsa sheets roughly to shape, and butt join an extra 40mm on to cover the width. Chine stringers were also bevelled to suit the bulkhead/bottom angles

Airplane guys will probably know this, as it's usually a wing sheeting method.

Sheets were joined by 1. butting them up side to side tightly, 2. taping the joint with masking tape pressed down firmly, 3. opening the joint and filling the V with PVA glue, 4. closing it and placing the sheets tape down on a flat surface, 5. wiping off the excess with a damp sponge, 6. weighting the joint along the entire length and leaving it to set thoroughly for about 12 hrs. When dry (test with a sharp modelling knife pricked into the glue) remove the tape and you are ready. Be gentle with it though. Once applied to the frame/cabin etc, you can reinforce the join on the inside with thin ply, glass tape, or cross grain balsa strips. If you are glassing the hull, it's still a good idea to reinforce the join.

Using a liberal bead of balsa glue on all areas, the sheeting on the first side was applied and clamped, and a few pins used in un-clampable areas. Sitting quite nicely so far, (these hulls having developable surfaces, like a lot of older models- ie- no steaming required,) so will probably be attacking the other side tomorrow.

Second side on now,-once set it can be trimmed and flipped over on the jig. Might have to make a few mods to the jig to support it, now the sheets are on.

Hull is now flipped over, levelled and secured to the jig again, using the extension legs on the cross-bars. The keel locating angle blocks have been removed from the base board for the keel to sit flat. Because of the 'rocker' in the hull, a cross-bar is placed at the bow to keep it up.

In this configuration, I can do the chine and mid stringers and deck, but will be doing the motor mount and internal bits before any of that, as it's easier to get at the inside without framing in the way.

Decided to laminate the spruce gunwale stringers to give the frame a bit more stiffness, as it will need moving around a bit before the side center stringers and sheets are fitted later. Also cut a 4mm ply plate for the engine mount to be fitted later. Still easy to fit internal floors etc like it is.

Gunwale stringer completed with 3 laminations of 5mm x 2mm spruce.

Removed the frame from the jig and re-mounted it using the transom clamped to hold it in place. Trimmed the laminated gunwale stringer with the belt sander to get the tops flush with the bulkheads. Trial fitted the shaft for position and glued in the motor mount plate. Also pre bent the side mid stringers (using boiling water run down them, a quick wipe to dry and clamping in place to set. These will be applied after the necessary internal work.

Finding new uses for the framing jig. Using this method to keep the frame from twisting while working on it right side up, and raised up for prop shaft/motor mount work, or while waiting for work to be done. Obviously it's a bit flexible still without the side sheets, and clamping it like this holds it in shape. Just levelled at the transom and clamped (as previously done) but with the addition of 2 front struts. Sighted across the 2 bars to get it all level.

I'm finding the jig is really useful, as you can clamp the model in almost any position, using a combination of the extension legs and cross bars, (also using cross bars for sighting level).
Not much progress at the moment as I've been busy elsewhere, but hopefully will be doing more soon.