ASSESSMENT for Safety in Small Craft

■ Draw the direction that the boat would turn if you went,

■ Mark on this model boat the following features
BOW, STERN, PORT, STARBOARD, WINDWARD SIDE, LEEWARD SIDE

■ Identify 4 Distress signals that are commonly used on a small boat.
a. The arm signal b. A smoke signal c. Flag signal: Letter N & C together or Square flag & ball d. Dye marker

■ Match the Fire Extinguisher with the types of fire each would be most useful for putting out by drawing out by drawing lines between the correct pairs,
Dry Powder – Engine / Water – Wood / Carbon Dioxide - Electrical

■ Explain 2 safety precautions one would take when using a fire extinguisher.
a. Check whether it’s appropriate for the type of fire
b. Make sure that all the electricity thinng is off.

■ Identify the following diagrams and explain the function of each,
1. Battery: Mainly 12V and gives spark for engine ignition. And also it gives power to electric devices including GPS Navigation system, echo sounder and radar. It is quite desirable to keep separate battery for use rather than using one.
2. Anchor / Danforth: A means of mooring the boat at sea temporarily and a useful maneuvering aid.
3. Bucket: Quite useful tool on a boat! Could be used as a fire extinguisher, water container, washing down, manual water pump and many more.
4. Boat hook: To pick something on water, pushing or pulling other boat, reaching for a rope when mooring at harbor and rescue use.
5. Rope: Rescue & Mooring.
6. Oar: Secondary propulsion in powerboat or main propulsion in a boat without a motor.
7. Compass: A navigation aid which tells you the direction, indispensable for night and ocean sailing with poor visibility.
8. Radio: A communication device and you need a call sign for it.

■ If you were at Position X, Give your potion by 2 methods.
a. Triangular compass bearing
Find three visible landmarks and get direction using compass. Draw lines from the mark on the chart then you will get a triangular are called ........(I forgot the name.) Also you could check the depth and check contour line on the chart to get your position.

b. GPS


■ What do the following symbols indicate on the chart?
a.Rock that is always under water
b.Rock(awash) - Rock that is almost same height as water level

■ Circle on the chart –

a. Rock that covers and uncovers with the tide - Probably in the small cirlce. Symbol for this rock is as below, but hardly recognizable in the chart.

b. A power cable - Wobbled line in the red circle.

■ What would be the time and height of low water on the morning of May 16?
0935 / 1.1

■ If the chartered symbol was +(2 1), what would be the actual amount of water over the rock at high tide on the morning of June 1?
Guessing,,
+ means a rock that is always under water and I think (2 1) means the distance between the rock and water level.
So, then, on the morning of June 1 is 1.3, that makes 3.4, I think.

■ A strong wind blowing against the tide causes the sea to be at greater disturbance with elevated height.
Wind creates wave, so it's about wave against tide.

■ Name 2 sources of a marine weather forecast.
a. VHF: Channel 16 VHF radio: Maritime New Zealand maritime radio service
b. Nowcast
c. MetPhone – dial 0900 999 + map area number

■ What is one feature that differs in a marine forecast from a land forecast?
Wind speeds over the sea are frequently much stronger than those reported in land forecast.

■ What could be a likely effect when wind, flow through a narrow passage?
Goes faster with lower pressure,,

■ If the weather and sea state suddenly turned rough, describe 3 effects that you would have to consider as a crew member, to ensure the safety of your boat and the crew.
a. Check for weather forecast update
b. Cehck for nearest port of distress
c. Maket sure that everyone gets PFD and check for emergency gear.

■ As a crew member on a boat, what would be your response in the following situations,
a. A fire broke out in the bow of the boat.
Shout fire so that everyone could be alert and tries to put it out with firefighting gear(fire extinguisher, water) while skipper set the bow at leeward direction so that fire doesn't get bigger.
If it's hard to put it out and expected to keep burning, call for help with whatever means you have and prepare for evacuation.

b. The boat was holed, and taking on water 1/2 mile from shore.
Alert everyone in the boat and report it to skipper and coastguard. Since it's not away from shore, head back to port while trying to stop or slwoing water from getting in the boat. Also be prepared for evacuation with safety gear.

c. A person fall overboard.
Shout MOB, everyone should be alerted and trying to find MOB's position. Skipper should set the engine neutral and make a turn back to MOB. Slowly approach to MOB and get him.

d. A person on board shows symptoms of hypothermia.
Report the incident to skipper and check for symptoms. Report it to skipper and coastguard for help.
Head back to the port whille treat him or her with food or drink with high calories.

■ Name 2 circumstances that would cause you to use a distress signal.
a. engine trouble
b. Injury

■ How would you call for search and rescue assistance?
a. Mobile whithin its range
b. Radio communication

■ If you needed to call for search & rescue assistance, name 3 thing that you could do to assist the rescuers
a.Name of a vessel
b.current postion
c.POB, number of people on board.

■ Ropes & Knots
a. Reef Knot
b. Bowline
c. Sheetbend
d. Clove Hitch
e. Round turn and 2 half hitches
f. Anchor Bend
g. Rolling Hitch
h. Figure 8 knot

■ Buoyage
Draw the correct path into the harbour around these markers.

a. South Cardinal sign: pass to the south of the signal
b. Isolated Dagner mark: pass with wide clearance
c. Buoy must be passed on port side
d. Buoy must be passed on starboard side.

What is the colour of a port hand buoy or beacon?
Red

■ Water Recreation Regulations.
a. A vessel must reduce speed to 5 knots or less.
- Within 200 meters of vessel flying ALPHA flag. This flag indicates that I have a diver down.
- Within 200 meters of the shore or structure
- Within 30 meters of any ****** in the water, and
- Within 50 meters of any person in the water


b. Bow riding is considered dangerous. In areas where local by-laws do not forbid Bow riding, the rule says that……………………………………………….
c. Explain the function and powers of a Launch Warden…………………………………
d. Water skiers within a ski zone are exempt from the 5 knot rule. Y
What are 2 rules that apply to ski boats?
- Must carry a lookout to notify the driver of every mishap that occurs to the person being towed.
- A verssel must not tow, between the times of sunset and sunrise.

e. What is the age for operating any powered vessel CAPABLE of speeds of more than 10 knots?
More than 15.

f. Some local authorities have regulations covering life jackets. Even if this is not mandatory in every area, it is generally agreed as a safety measure that each boat should


■ Collision Regulations.

a. You are at the wheel of the boat in the foreground.(A).

What would you be your FIRST actions on sighting the other boat?
Check whether we are in collision course; Check approaching vessel's compass bearing, EBL(Radar), sighting approaching vessel across fitting on the deck.

- In after short time this was the situation.

Are you on a collision course? Y

How can you tell?
Sighting approaching vessel across fitting on the deck is almost the same after short time, so it's in collsion coruse.

Which boat must give way? Not sure,
just regard it a head on situation and make a starboard.

What should you (in Boat A) do to avoid a collision?
Simply slow down and make a right(starboard)

What should the other boat do in this situation?
Look-out, slow down, make a right(Starboard)


b. In each of these situations, a risk of collision exists. In each diagram, draw the path you would take, that would be best avoid collision. In each situation you are on Boat A – The black boat

1.A, with same tack, but on windward, takes avoiding action.
2.A, with a motor, takes an avoiding action to make a starborad
3.A, keeps the course, B takes avoiding action.
4.A, overtaking vessel kepps out ot the way to starboard.
5.A takes avoiding action, starboard
6. Each boat make a starboard.






■ If fog came down while you were out at sea, and you heard ahead of you 1 blast of a horn every 2 minutes, explain what actions you might take.

a.
b.

■ For each of the following situations, explain,

a. the possible dangers to the boat from this
b. How could you prevent or minimize the hazard
c. Any possible causes for it happening

■ The boat becomes unstable
a. fds
b. bfds
c. fdsa

■ The engines stops
a. fdsa
b. bfds
c. fds

■ Wave height and shape
a. fsd
b. fds
c. fds

■ Low Freeboard
a. fds
b. fds
c. fds

■ Following Seas
a. fds
b. fsd

Drawing Deck Camber

To draw Deck Camber, you need 2 values. Length of Beam(Half) and height of Deck Crown.

First, Quadrant Method.
* Draw Beam(Half) and Deck Crown.
* Divide Beam into 4 and draw perpendicular lines at each divided point.
* Draw a circle with radius of height of Deck Crown and with its center at intersect between Beam and Deck Crown.
* Divide 90 degree arc inside of Beam and Deck Crown into 4 and draw perpendicular lines at each divided point.
* Draw fair line connecting all those intersects between 2 perpendicular lines.

Second, Quatering Method.

* Draw Beam(Half) and Deck Crown.
* Divide Crown Deck into 4 and measure the value of 1/4 Crown Deck
* Draw straight line from the left end of Beam to top of the Crwon Deck
* Draw a line which is 1/4 of Crown Deck height away from the line you drew just before and parallel to it.
* Draw an arc(3P)


The third, ARC method.(Start, End,Radius)
*

Lofting - 5.Calculation

Calculation.

Calculation for what?

It is to calculate Displacement of a vessel and diplacement is mass of the vessel(In this case, the dinghy we are building). Then, to calculate Displacement, we need to find out displaced volume of the vessel because...

* Displacement = Displaced Volume X Specific Gravity(of Fresh Water or Salt Water, it depends).

Then, Displaced Volume, how do we get it? As we all know,,
* Volume = Area X Height(Simply,,^^;;)

So if we know the area and height of the object, we could get the volume.
Then how do we get the area? Let me start with area calculation.


1.Area Calculation(Approximation)
Unlike rectangular, triangle, the surface we deal with is a fair line(Curve) and thus we do approximation for the calculation.

①Trapezoidal Rule

Using Trapezoidal Rule, we divide the object with same length(AE, EG, GI and IB are the same length) and regard the curve as a straight line, so simply think the object as a trapezoid.

Then, total area will be the sum of T(AEDF)+T(EGHF)+T(GIJH)+T(IBCJ)

T(AEDF) = 1/2*(y0+y1)*h
T(EGHF) = 1/2*(y1+y2)*h
T(GIJH) = 1/2*(y2+y3)*h
T(IBCJ)= 1/2*(y3+y4)*h

Area of ABCD = T(AEDF)+T(EGHF)+T(GIJH)+T(IBCJ) = 1/2*(y0+2y1+2y2+2y3+y4)*h = (1/2*y0+y1+y2+y3+1/2*y4)*h
=(10+29.24+35.51+39.06+20)*25= 3345.22
And I checked the area of ABCD in AutoCAD and it 3345. Voila!!

At first, I thought there should be differencde between the values I got from approximation and AutoCAD, but there's just slight difference and I think the reason is maybe AutoCAD is using the same logic to get the area.(not sure about this.)


②Simpson's First Rule

In Simpson's First Rule, to get the area of ABCD, you regard the curve DFC as a quadratic curve and multiply vertical length(y0, y1, y2) by a certain coefficient called Simpson's multiplier.

Area(ABCD) = 1/3*(y0+ 4y1+y2)*h

To apply Simpson's First Rule, you must divide the object into even number and Simpson's multiplier for Simpson's First Rule starts with 1 / 4 / 1.

Simpson's Multiplier for object with 2 equal segments : 1 4 1
Simpson's Multiplier for object with 4 equal segments : 1 4 2 4 1
Simpson's Multiplier for object with 6 equal segments : 1 4 2 4 2 4 1

Simpson's Multiplier

Then, let me calculate the area of object with 4 segments.

Area(ABCD) = Area(AGHD) + Area(GBCH) = 1/3*(yo+4y1+y2)h + 1/2(y2+4y3+y4)*h = 1/3*(y0+4y1+2y2+4y3+y4)*h


③Simpson's Second Rule
Simpson's Second Rule is similar to the First Rule.
Differences are like this.
- Regard the curve as a cubic curve.
- Simpson's multiplier starts with 1 3 1
- This is for more complicated objects.

But even for complicated objects, you could get area of it using the First Rule by dividing many more segements.


2.Volume Calculation(Approximation)

Here's Simpson's First Rule.
Area(ABCD) = 1/3*(y0+ 4y1+y2)*h
Here, y0, y1 and y2 are length of vertical line. We put lenght in there, it comes with area. If we put area in there, then, it comes with Volume.

So the Volum is
V=1/3*(AR0+ 4AR1+AR2)*h

For example, check the below.

Let's just say that it's a hull. AR0, AR1 and AR2 are the calculated value.(We can get it area calculation using Simpson's rule). With those value of AREAs, h, we can make new curve called "Area Curve" as below.

Here, ARo, AR1 and AR2 are the value of Area, not the lenth. If it is lenght, we could get the area from it but since it is the area, if we calculated the area of the object above, it becomes Volume.

3.Application of approximation.

Above is a body plan of the dinghy. Since the value we are fiding is a displaced volume, so we need to find the volume of the dinghy which is really in the water. So, that is, below LWL in Body Plan(as below)

* First, calculate area of each station in Body Plan.
* Get the full area value by multiplying 2
* Get the Function of each station by multiplying with Simpson's Multiplier and get the sum of Functions.
Then,, Since,
V=1/3*(AR0+ 4AR1+AR2)*h

= 1/3*(Sum of Functions)*C.I(Common Interval)

Note. the unit for area is "squrea mm" and unit for Volume is square M. So you have to convert "square mm" to "sauare M" by dividing it by 1,000,0000.

Now we have "Displaced Volume" and to get Displacement, we need to multiply the volume with S.G of saltwater which is 1.025t/m3(1,025kgf)

Thsus,,

Displacement =1/3*(AR0+ 4AR1+AR2)*h*1025

= 1/3*(Sum of Functions)*C.I(Common Interval)*1025


Cheers.

Lofting - 4.Angled Flat Transom

Tramsom is the surface that forms the stern of a vessel to which outboard could be attached to. Until now, we built all the hull except transom.

This time we draw 10 degree flat angled transom.
Before we go on 10 degree angled transom, we have to check the characteristics of 575mm Trammel Arm.

Length between the center of the hole to another is 575mm. If you draw a cirlce with 100mm radius on the othe end of hole and draw a line from the center of the other hole to the tangent of the circle, then, its angle is 10 degree.
With same logic, line to the tangent of 120R cirlce makes 12 degree angle, 200R makes 20 degree angle.

Now, with Trammel Arm(575mm, length between the center of the holes), you could make 10 degree angled line.


1.Drawing New Grid Line for Tramsom(Half)
First to draw a Tramsom is to draw Grid Lines for it. Before you draw Grid Lines for Trasom, if there's no space for it, you attach a piece of paper to it.

* With 575mm Trammel Arm, Draw outer transom line with 10 degree.
* Draw a line which is parallel to the 10 degree transom line, this will be the Center Line for the Tramsom. Then, draw buttock lines which are parallel to the Center Line.
* And now we have intersects between Transom and all the lines in Profile. Draw lines from all the intersects, which are perpendicular to the Transom(or Transom or all the buttock,,the same.)
* Now, Grid Line for Tramsom is completed.


2.Defining Beam(Width) of Tramsom.

* Now it's time to use Tick Stick(Pick-Up stick) again.
* In Profile View, using Tick Stick, measure the distance from AP to each intersect between Tramsom and all the lines in Profile. Then, mark the value on each line in Half Breadth.
For example, if you measure the distance between AP and WL200 intersect, then, mark it on WL200 in Half Breadth.
* When you measure the distance(mark it on the stick), it should be perpendicular to the FP.
* B200 and LWL were so close to each other, it just looks the same, but it is not.
* Then draw a fair line connecting all the marks in Half Breadth. This one has a chine, make sure that you draw the line separately.(Once from an end to chine, then, chine to the other end, or not, it's impossible to draw the line,,no batten for the stiff angle.)
* Then we get the fair line as below.

3. Drawing Beam
From the fair line in Half Breadth above, we could get the value of Beam(Width) of each point(line). So we mark it the Tramsom Grid line as below.

Draw fair line connecting all the marks above then, we will have transom as below.

Now we have the transom but it's not done yet. What we did is the shape of transome outside. Since transome is a plank with thickness, it has thickness and bevel. So we have to draw it too.

4. Transom PT
We will make a Tramsom with 30mm thickness, so draw a line which is parallel to the 10 degree tramsome line with 30mm difference inside as below.

Then, it's the same as we did before. We have another tramsom line(inside) and thus, new intersects and new grid lines.
So all we have to do is do the things all the way again with those new transom and intersects.

Cheers.

Lofting - 3.Stem Section

Now it's time to draw Stem Section in Profile which is a top view of Stem Face.
For this, we need to clarify some terms.

* PT: Plank Thickness of Top Side or Bottom.
* Moulding and Siding are the size of Stem Plank, length and width.
* Faying Surface is where it's glued and stuck toghether to some part.

Let's start drawing Stem Section.

1.Draw a perpendicular line to Stem Face of Canoe Body.

- Pick a point on Stem Face and then draw a perpendicular line to B50 line. This is a Center Line for Stem Section.

2.Draw a 50mm line from the intersect between Center Line B50 on the B50 Line.

3.Draw a PT4mm Plank Thickness.

4.Draw Plank with 32mm length from inside of PT and 15mm width. And make the corner filleted.

Below is how to draw Stem Section in AutoCAD.

Then make more Stme Section drawing to the joint between Hog and Stem Face.

Autocad - Understanding Plan & Assessment

There was an assessment for 2 weeks AutoCAD study.




2 weeks study covered basic commands with simple options, with which, we could refer to a beginner.

Before we go through the assessment, there was some time to read "FireBug" plans and draw it in AutoCAD and I found it quite interesting. What I was focusing on at the time was how to recreate it in AutoCAD, what commands I need thing.

But, to me, it was all about understanding, decoding the plans, not the CAD thing. Plans were not kind enough, so it seemed that many essential information were missing but it didn't. All the information we need were in those plans,,in the same page or another.

Then,,Why?

Designer and plans regard you as a pro, as a pro, you must be able to combine all the information in different places and sometimes, speculate it.

We didn't think about that at the beginning of class, almost all of us simply check the what's seen directly and started drawing. But soon after it, most of us should get back to plans, check the measures with a rule and talk about how we could get missing information. And this took quite a time and was a great practice, and for assessment.

Since we've gone through "reading plan", So this time, everyone was focusing on gathering information we need instead of rushing to workstation. After we got all we need, we started drawing.

And this time, we became the one who let other people to read the plan, we should be kind enough to keep all the information needed in the plan - All the dimensions.

Below is my final output.

Lofting - 2.Lines / Lines Plan

Lines Plan

Lines Plan is a drawing with three views of a subject(in this case, the dinghy) with many lines in it, including profile, half breadth and body plan.

Until now, all I did was a just preparation for lofting and now it's time to hit the board! REAL lofting.

One thing to note is that there is a priority or sequence in drawing lines which means if you don't have a certain line before you draw a specific line, then you can't. But if you have it already, then you can.


1. Grid Line(for Profile & Half Breadth)

Once we got a table of offset, we need to draw Grid Line first, which is a guide line and basis for each measures in the table.

- Station is common grid line for both Profile and Half Breadth.
- LWL, WL100, WL200, WL-60 are grid lines for Profile.
- Buttock 50, 200, 400 are grid lines for Half Breadth.

Note. LWL, CL and FP are called as a Datum Line which means reference lines from which all the measurements are made.

Grid Line in lofting on cardboard


- Size of cardboard for lofing is about 4000*1250.
- The highest point in Profile is 406, so added 14 as a buffer, LWL is 420 away from top edge of the paper.
- The widest point in Half Breadth is 530, so add some more, fix the Center Line from bottom edge.
- Make sure that those two lines(LWL and CL) are parallell.
- Then, mark AP and FP using measure of length. Distance between AP and FP is called LOA(Length Over All).
- Then, each station can be easily marked using CI(Common Interval, distance between each station) value.
- To avoid possible measuring error with a rule, mark each station point first using long tape measure as seen below and then, use common interval to mark station.

Precesion Method
- Make sure that each station line is perpendicular to those LWL and CL. Below is to prove and secure perpendicular station line.


* How to draw Station line which is vertical to the other.

Darw perpendicular station line.

ⅰMark station point using CI value on LWL.
ⅱMark two bisect point before and after the station on LWL.
ⅲDraw an arc from each bisect point upawrd and downward usin trammel arm with CI length.
ⅳTwo intersects of those arcs and station point on LWL are all right on the line, then it is perpendicular station line.

- When all the station line is done, then finish all the rest of longitudinal lines.



2. Sheer Line(Profile) and Deck Line(Half Breadth)

Sheer Line and Deck Line are an identical line but it only appears differently in each view.

Table below is part of Table of Offset which shows height in Profile and beam in Half Breadth. All you have to do is makr all the height at eahc section in Profile and beam at each section in Half Breadth, then draw a line using a batten

Note. To make fair(not kinked, smooth curve) line runs through all the marked points, we use a wood strip called batten and nails to fix the batten. It is quite important to get the right batten for each curve. Since there are many battens with varied thickness(flexibility and hardness - trade off), length and types woods, batten selection for each line is important.

- Thickness --> Flexiblity and hardness

- Surface --> Whether it's dressed or damaged, this could cause wobbled line or wood split stuck in your finger.

Battens is usually made of sitka spruce which is quite expensive wood.
Before all I know about the batten is, the one in batten pocket of sail which makes camber. Same name, different use but similar function.



3. Chine in Profile

Draw chine with value below.

4. Canoe Body and Stem Face in Half Breadth

Use Table of Offset and Stem Face deatils altogether to draw Canoe Body and Stem Face. Each angle of fair canoe body and stem face is quite different and if you use draw it at once wiht one batten, it's almost impossilbe to draw and batten will break. So you have to draw fair line of Canoe Body first and then draw Stem Face using stem face detail.

As you see here, since we drew the Canoe Body in Profile, now we can draw Chine, WL-60, LWL, WL100 and WL200 in Half Breadth. That is, intersects between Canoe Body and the lines I mentioned before are the start point of each line in Half Breadth.

From now, you could draw whatever line you want to draw, since we have all the start point of all those lines.

- All water lines in Half Breadth: Start points are intersects between Canoe Body and all the water lines in Profile.
- Chine in Half Breadth: Start point is intersect between Chine and Canoe Body in Profile.
- Buttocks in Profile: Start points are intersects between Deck Line and all the Buttock Line in Half Breadth.


5. Chine in Half Breadth

As you concluded start point of Chine in Half Breadth from intersect in Profile, now you could draw Chine in H.B.

6. Buttock 50 / 200 / 400 in Profile.

For buttocks, some of buttock might have kinked points in it, so you have to check buttock details just like the way you checked the Stem Face details.


7. 4 Water Lines in Half Breadth ( LWL, WL200, WL100, WL-60)

8. Body Plan
Now we are finished with Profile and Half Breadth of plan and Body Plan is the only one left for the plan.


1. Grid Line
We also need grid line for body plan with 4 horizontal lines (LWL, WL200, WL100 and WL-60) and 7 vertical lines (Center Line, B50, B200, B400 and its symmetrical lines to Center Line)

For horizontal lines, you simply extend all those waterlines from profile. Then for vertical lines, you just set up the Center Line first then, draw B50, B200, B400 and its symmetrical lines to CL.

2. Marking with Tick Stick(Pick-Up Stick)
Tick Stick is a long piece of paper on which you could mark specific point by ticking it. The reason why we are using Tick Stick is that it is more convenient and simple than measuring all the values with a rule.

On one side of tick stick, you mark all the height of the intersecting lines at the station and on the other side of tick stick, you mark all the beam of the intersecting lines at the station.
Then you mark those points on the stick to body plan and do it all over for all the station.

And just like you do it in Half Breadth, you draw half of each station in body plan because it's symetrical.

* Marking Height

Ⅰ.Canoe Body

Ⅱ.B50

Ⅲ.Chine

For Chine, we don't have its width(distance from CL) at the moment, just remember its height. We will get its width later.

Ⅳ.B200

Ⅴ.Sheer

For Sheer too, we don't have its width(distance from CL) at the moment, just remember its height. We will get its width later.


* Marking Beam(Width, Distance from Center Line)

Ⅰ.WL-60

Ⅱ.LWL

Ⅲ.Chine

Now, we have beam of Chine and the intersect is the exact Chine.

Ⅳ.WL100

Ⅴ.WL200

Ⅵ.Sheer/Deck Line

* Drawing Line by connectig point

Now we have all the points to draw a line. But one thing you should know is that this one has a Chine, which means it has Top Side and Bottom. And for each Top Side and Bottom, you should use different batten. One for stiff and another for fair curve.

And this is the final output and it is the Station Line 0.5. And by doing all the process above for other station lines, you will get total body plan for this dinghy.