So, let us have a look at the plans. What are the plans going to tell us? Well, they are graded on the grading system at 4 star **** for the experienced modeller. When we look at the plans we see at the top there is a side profile drawing of the boat. To the right of the side profile there is a front view drawn of the boat.
If we look carefully and can make it out; there is a baseline and a water line running parallel through these two drawings. We need to note this for reference further on.
If we look down from the side profile drawing, we will see a deck view of the vessel; underneath that there are our side profile line drawings. On this particular drawing which is the one for the time which will concern us; you will see it has been divided up vertically by 7 lines; drawn through the hull. It has also been divided up 8 times horizontally. These horizontal lines are marked off as ‘water lines’. Zero water line or we will call it the baseline also corresponds with the line of the top drawing on the side profile.
So, we know any measurements taken from this baseline will not only correspond with our line drawing; but, it should also correspond with the side view of the vessel. The vertical lines through the line plan drawing represent the frames or in our case they are going to become our ‘RIBS’. If we look below the side profile drawing; there is a deck profile drawing. This again has been divided horizontally and vertically and this time the horizontal lines are marked B1, B2 etc., etc., and these represent what they call ‘BUTTOCK LINES’.
For the purpose of our build; we do not need to really concern ourselves with that too much – we only have to be concerned (for this time being) with the vertical lines which are representing our frames and also our water lines. If you study the plan closely you can see and this is just for pure reference and information only – the Buttock lines represent, or should I say, they are the squiggly lines drawn through the hull on the side profile. When I say squiggly they are the lines that go from the deck edge down towards the keel and back up to meet the deck line.
Now then, if we move across the page from the line profile drawings; across to our right hand side of the plan, you will see there is a stern view drawn of the vessel and also, underneath that, there is a line drawing of the frames or ribs. This line drawing has been divided up again by horizontal and vertical lines and you will see on close inspection – if the scan allows – that the lines are numbered and lettered and they will correspond with the side profile and deck profile drawings.
Now for the time being, what we must do is concentrate and familiarise ourselves with these three drawings, the frame drawings, the hull and the deck profile. We then know and we can picture in our minds exactly where every frame fits or is located on the profile drawings and on our deck line drawing.
When we are happy with that; we next have to look and say to ourselves – okay – how are we going to power this model? This is because, on close inspection you will see, there are no propeller shaft locations drawn in on our line profile – nor is there any rudder positions indicated. Our first job is to find the location and transfer these from our side profile drawing and stern drawing to our line drawings. Also, at this stage, we have to consider – are we going to make the model – a working triple screw model; or a single screw model? (The screw means propellers in this instance).
For this build – it’s going to be TRIPLE SCREW – i.e. hopefully blinking fast.
So then; we can either – with pencil and ruler take measurements from our hull profile drawing (side hull) for the position of the propeller shafts and rudders and then transfer these to our line profile or we could actually trace them using tracing paper.
I opted to transfer these with pen and ruler; and I didn’t only transfer the measurements to the side and deck line profile drawing; but, I actually transferred it to the frame profile as well. The reason for me doing this on the frame profile will become evident later on in the build.
As we stand back and have another look at the plan, it does give rise to a lot more questions which we have to answer. As this plan doesn’t give any indication of what materials to build the hull from or what motors to power it; we have to find these out for ourselves.
We also have to work out what scale we want to build this model too, at the scale the model is drawn on the plan which is ½ inch to the foot; this will give us a model of some 31 inches long. This will be a reasonably sized model, easy to handle and will be fairly light and with today’s generation of brushless motors and LiPo batteries this will give us a startling performance on the water AS LONG AS WE KEEP THE HULL FAIRLY LIGHT.
When I originally purchased this plan and built the hull a good while ago; we didn’t have the brushless motors technology or even the LiPo batteries as we have today and when I built the hull – I made it to the scale of ½ inch to the foot – I powered the model with three Rocket 400 motors; with something like 15 mm diameter propellers. They were the largest propellers I could fit in and this model would not perform – it used to waddle round – similar to a lame duck and to increase the size of propellers I would have to do major surgery on the propeller shaft lines.
Armed with the above information, I was looking to build this model using brushless motors. This is when the first (shall we say) major setback hit me – but the price did! :) Two hundred pounds sterling is a lot of money to try and raise from the Banker
when the only thing you can say is well they are very good batteries, motors and speed controllers. The Banker then says the new bathroom suite will only cost us Three hundred pounds sterling and that is more important – so, I did lose that argument. We are therefore back to the drawing board.
Next thought was, make it 1/12 scale – 63 inches long – 17 inches beam and it makes a nice large size model. The only set back there was ME physically. So I therefore scaled it down, I couldn’t have the motors I wanted; the scale I originally wanted to build it would have been too large for me to handle and I eventually scaled it down to 5/8 inch to equal one foot. This is what the model is going to be built at – at this scale – we can comfortably manage 3 MTroniks – Vision 600 motors and also 3 NiCad packs. This will be the power. Also, we can comfortably accommodate 30 mm – three blade propellers on her. This should give her a lively turn of speed :)
That takes care of our ‘rough’ power requirements and we now must look at the material we want to use for the building of our model.
This particular shaped hull, lends itself perfectly to what is known as ‘Diagonally planked’ hull. Ironically the original boats were double diagonally planked and in between the two planking layers there was a layer of Calico canvas. The planking, although we could longitudinal as we did on the Cervia build, we are going to opt to diagonally plank this hull. In actual fact, it will be double diagonally planked. The inner layer of planking is going to be Obechi and the outer layer of planks is going to be Mahogany.
That takes care of the ‘skin’ of the vessel – but what about the framework to hold the skin. Here we are going to use a high grade birch ply – of 1/8 inch thick for the construction of the frames; the keel & the motor mounts and several other mounting components. This particular birch ply I purchased from a Company www.mantuamodel.co.uk
– you will find that it is slightly more expensive than the standard modelling birch ply because it has six veneers to make up its thickness. This plywood is extremely strong, for its thickness, and I believe they use it a lot in model aircraft – but hey its ideal for the purpose we are going to use it for :) so now we have outlined a good few things and we are quite happy with the plans – we can really begin to proceed with taking information from the plans and applying it to our building materials. Since we are going to scale up these drawings to 5/8 of an inch to the foot – my first plan of attack was to photocopy the frames drawing, which I did do, and that increased the drawings to the appropriate scale i.e. it worked out that they measured about 10.5 across the widest point of the boat and this equated to 136% approximately. This was fine, because I had to allow 1/8 inch for planking; so, I printed the frames off at this scale. I then moved on to increase and photocopy the lines side profile. This is where I hit the first snag. The overall length of the hull should have worked out in the area of 39 inches or thereabouts. 47 inches was totally unacceptable and that is what they came out at.
So plan B was scrapped on enlarging the side profile on the photocopier.
Plan C was to draw out on the 1/8 plywood we were going to use, the side profile at the correct scale. This I did; by starting off drawing a base line; to correspond with the base line on my plan; then followed by the water lines drawn parallel to the baseline at the correctly spaced intervals for the scale.