Space is at a premium in this craft for placing all the power equipment that needs to be hidden. I need a 6v supply to run possible bits of equipment so I have a voltage reduction unit that will fit behind the main motor and supply power to a distribution board, which is under the rear seat.
I will need to position the board over the top of the propeller tube so I need a block that will slide under the tube and allow me to screw the unit in position. This piece of wood took more time to make than I want to think about with cutting the tube slot and making clearance for the oiling tube.
The voltage unit now sits over the prop tube and wires can be fed through the under floor tubes to the rear and back inti the voltage distribution unit.
The motor was positioned when the prop shaft was fitted so I’m confident that it will run OK however because it was fitted early on it may need a final adjustment when everything is finished.

A change from plank prep and before the final planking stage I’ll look at the front cockpit
Next job is to decide what level of detail should I do in the front cockpit, the plans call for a fixed floor and a small bench seat, and this is what I will use as a basis for a little more detail. Since I have all my electrics running through the lower part of the hull, I will still need access to this part of the hull so the floor needs to be removable and an access hatch should I need to get to the wiring. I have made a false floor with a trap door and taken time to plank the floor in the same style of the main floor and the main deck, both the trap door and the main false floor are held in position with a number of small neodymium magnets this allows very quick access without the need for screws.
The bench seat is simple – a bench stood on four doweling legs, each of the lrgs has a small magnet inserted in its end and then their opposite pole magnets set into the floor, again this give instant access if needed. The craft can be piloted from the front cockpit so needs a duplicate dashboard and steering wheel, this will be mounted on a small angled table which again is mounted in position on a small rail with magnets inset which allow quick removal.

The kit does supply a deck that is laser marked with planks, it’s supplied in 6 pieces which are remarkably accurate and fit the hull really well. I started by temporally pinning each piece to the hull to make sure that all the planks will line up. I have altered the main cockpit area, which means that the supplied planking pieces will not line up as I thought. However since I am planking the deck the supplied markings are not required but for those that do not want to go to the expense and time of doing a planked deck the supplied marked pieces are good.
I use epoxy for attaching the deck pieces and use brass pins to ensure the deck stays in place while the epoxy sets. Leaving overnight, and then trimming the deck to match the contours of the hull and the cockpits/rear hatch. I want some sort of division between the deck planks and the internal panels of each cockpit; this will be in the form of an angle strip of walnut timber. The angle pieces are to be 6mm angle x 2mm thick, as this is not a section of timber available to purchase I will make lengths to fit around all the cockpit areas.
The 6mm x 2mm Walnut pieces are actually walnut planking, I use two lengths of brass bar laid on some PTFE sheeting to make sure the pieces are glued together without it sticking to the bench When it comes to the corners I didn’t want just square corners but a radiused joint the same as the laser cut deck sheets. This was done by turning some “bobbins” out of walnut and then cutting into quarters theses will give a nice radius when sanded and a smooth transition between the angle and corners. In addition to the angle between cockpit and deck I will also place an angle piece around the perimeter of the deck and hull sides, this will give a clear division between the painted sides and deck.

After the skins have been trimmed and sanded and the balsa bow blocks are fitted, its time to fit the outer keel. This is made from 9mm ply and is in 3 pieces, these have to be glued together before fitting to the hull. A quick check against the plan is advisable before finally glueing them together the pieces are really very accurately cut so they can be glued together knowing they will fit the hull. I first dry fit the keel making sure it fits the hull and gently sanding any high spots until it fits exactly. I then drill four 3mm location holes through the keel and then spot through onto the hull drilling to a depth of 10 mm. Epoxy is then applied to the joint area and with the four bamboo dowels in place the keel is pressed into place and any excess epoxy is removed, the hull is left to cure.

The balsa bow I think is one of the most difficult things to get right, I would always prefer to have a skin that goes right to the point of the bow, even if it makes it a little more difficult and possibly having to apply steam or heat. The blocks are made up from four pieces that are glued together using aliphatic glue, then comes the shaping. I know where the curve starts and where it finishes it the bit in between that is difficult, I use a card template which has the curve profile cut into it, I can use this to ensure both sides are exactly the same, being able to flip it side to side on a fabric tape hinge at the centre keep it in position. this card only shows the first cut, another is used for the downward sweep. (last picture)
I find the rough shaping is better done in the first instance using a coping saw but be careful not to remove too much, then using a selection of curved sharp chisels to get the final shape. One the balsa is to the card template then the block has to be curved further to the final chine line which is half way down keel part K9. To do the final sanding I first soak the balsa in a wood hardening solution, this stops that resulting fury surface after sanding.

Now the box and the associated formers are assembled its time to start to look at the skinning process
The bottom skins are the first to be epoxied in place, the pieces are cut nearly to the correct shape so they can be applied with minimal further shaping. The side which aligns with the keel needs to be a perfect fit and level with the keel bottom. For ease, the the bottom skins only go as far as the 2nd bulkhead and the bow is then made from a balsa block which has to be formed, more on this process later.
The skin is dry fitted and the the bulkhead profiles are marked so that the skin can be pre drilled with 0.5mm holes at suitable intervals along its edge and bulkheads. 30 min Epoxy is mixed and applied along the jointing surfaces. The four extreme brass pins are tapped into place to ensure the alignment is correct , the remaining brass pins are then tapped home and any excess epoxy is removed and then the surfaces are leaned using methylated spirit.
I applied large rubber bands around the hull to ensure that all the surfaces were in contact with all surfaces and then allowed the skin to dry. Unfortunately I forgot to photograph the bottom skin process so the pictures are of the side skin fitting
With all skin fitting there is always excess material to be removed after the skins are glued in position and sometimes its more than you would want to plane away so I use a hacksaw blade to get rid of most of the excess. To mark how much is to be removed I use a scrap piece of wood and a pencil to mark the cutting line, it has a slot and a hole - this rests on the chine whilst the slot arches over the excess and the pencil scribes a line at the same level as the chine. The excess is removed leaving a small amount to plane and then finally sand to a perfect level.

The chines are in a number of pieces and have to be glued together, the instructions suggest that the pieces are pinned to the plan and glued together. To do this you are able to construct an upper chine and a lower chine at one time, the process is then repeated to give a full set of chines.
The upper chines are glued in position first, making sure they laid flat on the formers this now gives some shape, from and rigidity to the construction. Next the lower chines are fitted, again making sure they lay flat on the formers. WE now have a skeleton of a boat ready for skinning.

The prop shaft is next to be fitted, the keel has been fastened in place, so I now have to complete the hole through to the inside of the box which means a long drill has to be made. Since the only wood to be removed is the 9mm thickness of the base which is ply. I have used this method before and it involves using a piece of brass tube (8mm) and cutting some teeth in the end like a hole saw because this is a one time use the brass teeth will easily stand up to cutting plywood.
Mounted in a hand power drill I start from from the underside and the brass core drill is inserted into the square hole left by the construction of the keel. I clamp a piece of scrap wood to the area where the hole will exit into the box to stop it damaging the planked floor, then gently pushing forward the hole is penetrated into the scrap wood.
I had drawn in the position of expected exit hole and to my amazement it came through in exactly to predicted place, the shaft I a good slide fit in the hole so it retains it in position whilst it is used to position the motor. The hole finished I now need to make the motor mount
The motor mount is made from 3mm aluminium sheet, a detailed drawing was made and calculations of the angle and hole positions. The piece is guillotined to shape, debured and corners radiused. The piece is bent to the correct angle and then the holes are marked out on the surface plate according to the dimensions on the motor plan. The motor is fastened to the bracket and the solid aluminium connector placed on the motor and prop shaft, this allows the position of the motor mount to be accurately placed and the fastening holes marked out, I use 4mm studs for the fastening the tapping size holes are drilled and then I use a wood hardening solution poured into each hole, this soaks in and makes the wood hard enough to be tapped M4, when set and tapped the studs are inserted with a drop of epoxy in each hole.
The power train is now positioned and will run even with a solid connector, I can now remove the motor and mount whilst I continue with the rest of the build

The inner keel is made up of 5 separate parts all made from ply, each piece is trimmed where the connecting pieces were and then lade on the plan and adhesive applied and pined in position leave over night to cure.
I chose at this point to make sure the hole (8mm) for the prop shaft was clear and the correct size, while attaching the strengthening pieces K6, if the pieces are glued correctly it leaves an 8mm sq hole at the correct angle making fitting of the shaft at a later stage very easy. I also made additional pieces to extend K6 to the stern so it created additional thickness to drill holes for the rudder and the water scoop, The rudder in the plan is small and not the type that is commercially available so it requires additional thickness to drill an 8mm hole, the additional hole (6mm not shown in the plan) is for a water cooling scoop which is required for cooling my ESC. Not everyone will require this scoop.
I don’t at at his point secure the propshaft as this will be done when the motor position is confirmed.
The keel now in one piece has to be glued to the box ensuring that it is on centre both at the bow and stern and straight all of its length I use epoxy to secure the keel to the box making sure it is also at 90 degrees to the box

03 Box Construction
Now we have sorted the slight deviation from plan we can construct the basic box, four nicely laser cut panels form the balsa wood box , the side have a partial cut in the height of the side which has to bend to follow the angled side of the box, I use aliphatic wood glue to construct the box, the sides of each piece has to be lightly sanded to remove the tabs which secured them to the original sheet and also to remove the sooty deposit which is left by the laser cutting. The side panels are all marked as to where any of the bulkhead pieces need to be aligned. Using some heavy brass bars to support the glued sides they are left to dry overnight, the end panels are glued in place the following day.I decided at this stage to leave out the centre bulkhead with a view to changing it dependant on the size of the motor housing, however I put it in position to ensure the side panels are at 90 degrees I will cover the planked surface with sticky backed paper.