Project

Mechanical Surfboard Rack

4/30/2014

Matt Wilson

ContentsIntroduction...........................................................................................................................................1

Chosen Idea.......................................................................................................................................2

General Research...................................................................................................................................3

Specification..........................................................................................................................................5

Solutions to Make the Rack into a Mechanical Rack.........................................................................7

Spring release................................................................................................................................7

Electronic retractable arms (Electric scissor lift)...........................................................................8

Pneumatic Arm..............................................................................................................................8

Conclusion of the 3 Solutions............................................................................................................9

Pneumatics......................................................................................................................................10

Air Cylinder - Pressure/Force Diagram.......................................................................................10

Planning...............................................................................................................................................12

Planning Order.............................................................................................................................12

Materials..........................................................................................................................................13

Material Properties Tables...........................................................................................................14

Planning Conclusion........................................................................................................................17

Construction Notes..............................................................................................................................20

Presentation........................................................................................................................................23

Evaluation............................................................................................................................................25

Final Conclusion...............................................................................................................................28

Surfboard Rack

Project

Introduction

Throughout this final year I am going to make a working mechanical project, which I can show at the end of the year with a presentation and demonstrate what my project can do. During my project I am going to show how and why I have chosen the idea I’m going to make; come up with 3 different mechanical instruments I could use for my project and why; produce a design of the project with 3D modelling; show my planning and also how I am going to make my project with a step by step progress until the final product.

For my project I have to choose out of 3 ideas I have come up with and write about them. Then once I have gone through the 3 ideas, I then have to decide which one I am going to make. Here are my 3 ideas which I am going to choose from:

My first idea is a surfboard rack- the rough idea that I have so far is that it has 2 supports coming from the ceiling which are secured by 4 bolts, which are joined by arms that join to the supporting pole. Coming off these poles are the rack poles that come out each side with foam protection on the bars; this is to hold the surfboards. The 2 arms have 1 pole joining them up but on the front arm it will have a mechanical mechanism, so it is able to lower the rack and retract it, in a slow and safe manner.

My second idea is a vacuum chuck- this idea came about from a copper component at my place of work, that needs grinding but it always seems to lift when it’s being cut. Having a vacuum chuck will keep the copper component down on the table by having grooves cut out which allows the air to be sucked out.

My third idea is an adjustable TV stand – the TV stand will move up and down as well as left and right, using a remote that has a jog-stick you’ll be able to adjust your TV to whatever direction you want.

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Chosen Idea

For my project I am going to make a surfboard rack, the reason why I choose to make a surfboard rack was mainly for the sole reason to store my surfboards but if the rack is successful enough I could plan to take it further. My ideas though for this rack will have to be something different to any conventional surfboard rack and which will also be easy to install or construct, that will benefit the customer compared to all the quick grab and go wall racks. There is a high demand for surfboards, seeing that it is the quickest sport being picked up by youngsters since short-boards started to hit the professional scene. This means that if I can make a rack that is of a high quality and meets my highest specification without any problems there is a demand for it. Also people in England have many surfboards because of the unpredictable swells (size of waves) so they will have a variety of boards that could start from 4ft to 9ft long. I have also decided to choose this idea because it is also easy to make and the quickest, with just a few things that may take longer, while still being a great product in which people will buy.

During this project I am going to show that I am:

Capable of coming up with my own ideas Producing a specification of my rack Coming up with a design, with sketches and CAD drawings Evidence of progress and that I am actually making the rack myself and not buying

parts Turn my designs into reality Overcome any obstacles and recording any that have occurred Come up with a presentation of my product by showing how I came about the idea to

the end product

I am planning on finishing this project before the deadline so I am able to show my finished product during the presentation.

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General Research

For some research I went online and had a look at some surfboard racks to see what has been made before, while also getting some ideas that I could emerge into my design. I used Google to research and get ideas. The pictures I got from Google images.

Here are some of the surfboard racks that I liked and to help me to get some ideas I could emerge to improve my own:

Here are some surfboard racks I have found on Google images. As you can see they are all built for use inside of a house. Most of them have stands coming from the floor which are adjustable. The other 2 are ceiling shelves, which have been bolted to the ceiling with the arms that are wrapped in piping foam where the surfboards will lie. The picture with the 2 surfboards, with arms coming off both sides of the support stand is quite similar to my idea and picture of what I will build, that picture has given me great insight of where my project will go and look like.

Here are some pictures of rams, this is what I feel will be the best mechanical part to move the rack up and down. This has given me some ideas of what I could use to move my surfboard rack with and how.

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After doing some research I found that there is a high market in wall racks for surfboards, this makes it easy for the customer to install the rack at a cheap price, yet this is only a good idea for a room which is in a house. If someone will need to store surfboards in the garage it’s best to have the surfboards stored on the ceiling. This is where my idea will come into play, while doing my research I found that there wasn’t much of a market for ceiling storage of surfboards, if there was, they were simple racks or shelves, this means that these racks aren’t a simple reach and grab, making it awkward for anyone (specially someone who is short) to quickly pick up their surfboard and go.

Specification

Due to this being a project for college it has to meet the specification for the pass grades of this assignment as well as the specification of what I want my surfboard rack to be like. To make it a unique design so it could be sold in this market I want the rack to meet these specifications:

Cost

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Time Board Security Foam sleeves to stop scratches or dings to the surfboard Decorative for house use Long life material and rust protection (protection from salt which the material will be

prolonged to) Able to make the surfboards easily accessible to reach for quick grab and go (have a

mechanical arm to lower rack down and up) Able to be put up in any room in the house, especially the garage Lightweight and sturdy Able to install and put together easily

Throughout this project I want to be able to tick off all of these points once I’ve finished off my product. If I can’t I want to at least keep to 80 - 90% of my specification.

Cost - is an important factor, I want to keep the price of my product under £150. I need to think about what I would need to do to make a profit, if I was to sell my product commercially.

Time - time as well is another important factor, I need to have finished and have my product up and running before March 2014. If I can’t keep to this deadline then I will have failed my assignment and won’t have anything to present when I do my presentation. When making my product time is money, especially if I was to take the product to be sold commercially. The reason is that if I take ages to make my product, then the time making it could cost more than the price of the rack. The longer it takes to make the more the price of the product is, so the quicker I can make the product the cheaper it will be and more turnover I can make from the product.

Board Security – having bars on the end will help to stop boards from sliding off if not on properly and when the rack is lowering or retracting.

Foam sleeves – foam sleeves will help to protect the surfboards from any scratches from sharp material that may be produced after a lot of use, it will also stop the material from getting rusty from the salt which will be on the surfboard and stop denting the boards.

Decorative – having my rack decorative is a great way of selling a product, no-one wants to buy or have anything in their house that will look out of place and looks tacky or not appealing. An eye catching design will grab the customer’s attention, this is the first thing people will look for when buying any product.

Life – I want my rack to have a long lasting life, no one wants a product that fails or breaks within a short time and I want my rack to last a long time.

Accessibility – I want the rack to be easily accessible for the consumer to take off or put away a surfboard. I don’t want the consumer to have to get a ladder to reach the boards or have to jump to get the board onto the rack.

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Where it will live – I want my rack to be able to be put anywhere in the house or even anywhere in the garage. I am aiming for this product to not look out of place where ever it goes.

Lightweight – having the rack lightweight will make it easier for the consumer to install and it won’t put strain on any of the supports arms or the ceiling.

Installation – my product will need to be easy to put together, the design of it should be basic so it won’t be too complicated to make but still be able to look good and work well. I want the installation to be not only easy for me to make but also easy for the consumer to install in the house or garage.

Solutions to Make the Rack into a Mechanical RackSo far I have come up with 3 solutions to make my rack so it can be retracted or lowered using a mechanical instrument.

Pneumatics arm Spring release Electronic retractable arms

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Spring releaseSpring release mechanism is a good and cheap way of making a shelf or rack lower down. It’s easy to install and construct, but using this as the mechanism for my rack isn’t going to be a good option. Even though it is cheap to make or even buy and easy to install, the springs will lose its tension over time which means you will have to push the shelf back up to its original position. Refer to IMAGE 1, to show how a spring release will work.

http://www.sparknotes.com/testprep/books/sat2/physics/chapter8section4.rhtml

Hooke’s law is described by:

F = -kx

Where F is the force exerted on the spring in Newtons (N),

k is the spring constant, in Newtons per meter (N/m),

and x is the displacement of the spring from its equilibrium position.

http://www.education.com/science-fair/article/springs-pulling-harder/

To work out what spring I will need to use, I have to know the distance extension of the spring and the constant of the spring. So far I have done some rough estimations of the weight of my project. Using Solidworks on my design I have found that using steel, the rack will weigh 15.802Kg. Using the equation F=Mg. 15.802x10³x9.81 = 155.02K.N

After using the Force Equation I can work out what constant spring I will need for a spring release mechanism.

155.02x10³=Kx172x10ˉ³. Rearranging the formula I get K=F/x = K=155.02x10³/172x10ˉ³ = 901.28 KN/M constant.

The answer I got is very high. This means; to buy a suitable constant spring would be too expensive and even making one would be beyond my skills.

IMAGE 1

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Electronic retractable arms (Electric scissor lift)The electronic retractable arm is a design which is similar to the scissor lifts that are used to do work at high places that need multiple people, but this will be smaller so it will be able to lower and retract the shelf at a slow and safe pace without the user having to pull or push anything down or up. It’s reliable as long as there is electricity going to the motor, safe and strong. The only problem with using this is the price, work involved to make it and it’s not easy to install, plus there is a lot of electronics involved in making this mechanism which is out of my knowledge. Refer to IMAGE 2, which shows how a retractable arm works.

IMAGE 2

Pneumatic ArmA pneumatic arm is a good reliable mechanical instrument which allows you to lift or even lower heavy objects at a slow and controlled manner. Pneumatics are used widely in the engineering industry, using air to move the shaft in or out by pumping compressed air in and using a valve to let air out to lower the ram. A compressor will pump compressed air into a cylinder which slides the shaft out and releasing a valve to retract the shaft. It’s a simple and easy method of lifting items. Even-though pneumatics can be very expensive mechanical instruments, it’s very easily salvageable from scrapyards. Refer to IMAGE 3 for a picture of a ram.

IMAGE 3

Conclusion of the 3 Solutions

After going through my 3 solutions of which mechanical instrument I am going to use, I have decided to go for a pneumatic arm. I have chosen this because I reckon it’ll be the best way of lowering and retracting my surfboard rack, in the way that I have imagined. It will lower the rack slowly due to how much pressure I allow the air to be pumped round, making the user not having to struggle getting the surfboard down or up.

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The spring release for instance is only one speed, but that wasn’t just the reason why I didn’t choose it. I didn’t choose the spring release because you will also have to push the rack back up and lock the hinges in place so it won’t fall back down. Also the springs wear out quickly and rust, meaning repairs will be frequent. Using a spring release mechanism, is the cheapest, easiest to make and install but the cons have out- weighed the pros.

Using an electronic retractable arm is a great idea and great way of lowering and retracting a rack, the problem of using this mechanism is the time and material needed to make it, also the electronics behind it is a lot and I don’t have a good knowledge of electronics. If I did use this mechanism, I would have to make all the individual arms and attach them to the rack and the design would have looked tacky. The reason why I haven’t chosen this idea is because of the electronics behind it, the look it will bring (old Victorian) and the time and material to make all of the individual arms. If I was to sell this product on the market, I would use a retractable arm because it will be cost effective with materials and time.

When making my finished product, I have come up with an idea that will make my rack more efficient. By making the joint bar slide in a ball bearing or bush and have pins either side of the bearing, I can assemble that to the support arm. This will enable the rack bar to rotate with the hydraulic arm, making a steady and smooth descent and retraction. Due to the fact that I am using a bearing for this, the wear should be minimal compared to not using a bearing. Also by using pins either side, this will ensure that the rack bar won’t slide back and forth in the bearing, this will also prevent the rack bar and the rack support from fracturing, from shear forces and deformation due to elasticity and ductile fractures.

Pneumatics

For the pneumatic circuit (REFERENCE 2), I have decided that I want a two way circuit. I want the rack to retract and descend, this means that I will need a two way release valve circuit. To compress the air, I will use a compressor no bigger than one used to blow up air beds, this is because the surfboard rack will be so light weight, and I wouldn’t need anything more powerful. Once the air has been compressed, it will go to a valve button; this will determine which way the air will go into the ram. On the ram there are two places where the air can enter, from the bottom and from the top. One will force the ram back up and the other entrance will force the ram down. Having the button valve, this can be determined by the

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user. Because I am not using a powerful compressor, I won’t need to have it plugged into the mains. The compressor can have its own power supply like a 9 or 12 volt battery.

To make sure that the ram isn’t damaged by constant air being pushed into it, I will have a system where there are limit switches. This means that when the ram pushes past roller limits and pushes them back, it switches the air being forced into the ram. There are two limit switches, one for when the ram retracts and one for when the ram has attracted out, both do the same thing, once they have been activated and air goes out the exhaust exits.

Air Cylinder - Pressure/Force Diagram

Figure 1

The force exerted by double acting pneumatic cylinder on outstroke can be expressed as. The force exerted on in-stroke can be expressed by the formula:

F = p π (d12 - d2

2) / 4        

Where:

d1 = full bore piston diameter (m)

d2 = piston rod diameter (m)

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This is a graph and formula to work out the force needed to move the pneumatic arm. So to work out the force needed to move the ram arm I have used the formula.

F=100 * 3.14 (0.05^2 -0.0 2^2) / 4 = 165N. So I will need about 165N – 200N of force.

http://www.engineeringtoolbox.com/pneumatic-cylinder-force-d_1273.html

After using the formula to work out the force needed, I have come up with; that the arm needs a minimum force of 165N to move it. But by retracting the arm, I have determined that with the weight of the rack and the surfboards it should need no more than 200N of force.

Planning

Using my work place I will be able to order the appropriate size material needed. I will be able to do this by using the same suppliers they use to order their material. I will also be able to make my project at work by using the mills and lathes that are available. I will be able to make most of the parts for the assembled surf rack at work but I will have to do some welding to join some of the components together, as you can see by the provisional sketches. Because I don’t know how to weld I will be getting some help from my dad, in which we will Mig weld parts of the components together in our garage. Even though my dad is a qualified welder he will only be supervising during the operation, I will take pictures of me welding to

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show evidence that I was welding, as well as taking pictures of me using the lathe and mills. These pictures will also be used to show the stages of my surfboard rack being made.

Due to the fact that I will be welding in a garage I will have to make sure that the garage is clean and tidy to health and safety regulations before carrying out the welding. I will also have to make sure that we are wearing the appropriate PPE and that the mig welder is up to standards.

For my planning I am going to have stages from designed drawings to finished product (FIGURE 2 GANT CHART). These are the stages I will be taking in order to achieve this goal and by keeping to this plan it will help make my project in sufficient time and organisation.

Planning Order1. Design Drawings (Assembly drawings and Component Drawings) 2. Order Material through work suppliers and order compressor and ram 3. Order appropriate measuring instruments and tools e.g. thread gauges, plug gauges,

cutters and turning tips 4. Planned particular Fridays to use work machines 5. Make components on mills and lathes 6. Check that certain components fit together and check that compressor works with ram 7. Weld together certain components 8. Fit Ram and compressor to product 9. Test final product with many different surfboards 10. Put together a presentation and practice

Materials

What material I use will determine the life and how easy it will be to look after. For the fact that I am only making a prototype at the moment I have decided to make it out of mild steel. If I was going to mass produce this project for commercial use I would use aluminium. I would use aluminium because of its light-weight properties and for the fact it doesn’t rust and takes years for oxidisation to eat through, due to its oxide film. So for most parts of this project, I will be making them out of any mild steel but I may need to use certain types of mild steel for welding purposes. To help prevent the steel from rusting I will need to apply some water resistant paint. Doing some research online, I have found that most paints that help to prevent rust has enamel gloss in; obviously the more I spend on the paint, the more

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the paint will prevent the material from rusting. Picking the paint with enamel gloss, will be the most logical paint to use because of its properties from preventing rust. It may be more expensive but in the long run it will be cheaper, also because of the gloss the paint won’t flake.

Using this site http://www.npl.co.uk/upload/pdf/bimetallic_20071105114556.pdf i have found a table to show corrosion when different materials are in contact with each other. I have used this to help with the materials I would use for prototype and the real product. Because I am using certain mild steel for welding, I wanted to make sure that aluminium and other mild steel wouldn’t affect and cause corrosion. From looking at the table (FIGURE 3) I can see that using mild steel with aluminium is a likely chance the additional corrosion will occur.

Material Properties Tables

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FIGURE 3

On my bracket I need a pin for the bracket to swivel and pivot on a bar of material. I need a material that has a good shear strength and hardness (FIGURE 4). The chart shows cold worked steel at 1.0°C has the highest shear strength.

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The equation for the shear stress is Τ=F/A (F=Force) (A=Area of Cross Section) so I will be having a force acting down on the pin and in two places a force acting up. The Force is Mass x Gravity.

To work out the force I times Mass by Gravity = 15.802x10³x9.81 = 155.02x10³KN.

The cross section is πr² = πx5² = 78.54mm²

Τ=155.02x10³/78.53x10ˉ³ = 1.974 MPa

I can see that most material can stand the shear force needed for my pin (FIGURE 4). For my project I have decided to use silver steel, not just because it can stand the shear force but also the stock bars and ground to size, giving it a good fit.

Attached is a Sustainability Report of my project (FIGURE 5). I have used SolidWorks to generate this; which has helped me to understand the manufacturing needs to make this project, as well as the impact it will have on the environment. It has told me to the weight of my project; it was able to give me these results by me telling the program what material I will use.

FIGURE 4

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Planning Conclusion

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The stages that I have laid out in numerical order above (see Planning Order Page 12), is the order I will be making my project in, I feel that this is the most efficient way of making my project in an organised fashion and the quickest time without losing the quality of the final product.

By making the drawings first, it will help to see what size material I will need to order and the length, it will also help to see what cutters I will need and measuring equipment, so some stages seem to roll together nicely in order, I could order the material, cutters and measuring equipment together, due to the fact that I could give my employers an organised sheet, which could be in a table to show material then different sizes and lengths and then measuring equipment and cutting tools for that components material. This will help me to see, once the material is in, that this material goes with those cutters and measuring equipment, so everything will be together so I’m not looking around for equipment and wasting unnecessary time.

Due to the fact that I don’t use all the machines at work, I will have to talk to certain areas at work, if and when I will be able to use their machines to make the components for my project. This is the part that could drag out the making of my product, if the machines are occupied then I won’t be able to use them, I will only be able to use them when there is no job in the machine, so I will have to plan with those areas when I am able to work on my product. When making my parts, I will have to determine whether or not I will have to turn the part on a lathe before any milling is needed to be done. Some parts will have to, so for good planning procedures, I should use the lathe and turn all the parts of the project, that need to be turned first and then move on to milling.

Once all the components have been made I can then check that they have been made to the drawings, within tolerances and start to assemble them. By assembling some of the components I can start to see the product taking shape. I will also then start to weld the base supports to the stands. While welding these parts I will have to make sure that the stands don’t bend or weaken in certain parts, I’m more concerned that the stands will bend due to the fact that the stands will be mild steel tubing to make the product lighter. Also while welding I will have to make sure I am keeping to the health and safety regulations like I discussed earlier.

The final part of the assembly will be fitting the Ram and compressor. The reason why I will install the ram and compressor last is just in case one of the items didn’t work when I tested it earlier and because it will be the most complicated due to the wiring of the pumps, but once they have been installed and the product has been successfully assembled I will be able to start the testing of my product.

To help me organise my construction of the project, I have made a Gantt chart (FIGURE 2). I have done this to make sure that I am within the time schedule, as well as making sure that I am keeping to the designated time frame. When making the Gantt chart I allowed myself a few weeks extra to make sure that if there are any delays such as the order of the materials and cutting tools, then I will hopefully still be within the time frame. This will only work

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though if I keep to the time schedule of this Gantt chart. As long as I keep to my planning schedule I believe that I will finish my project in sufficient time and allow plenty of testing time and allow plenty of time, for any improvements, as well as give me time to practice my presentation and improve on that.

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Figure 2 GANTT CHART

Construction NotesDate Description of

operationComplications

6/2/14 Started on some milling. Started making the brackets. This is due to the fact there is no turning operation. I just blocked up both brackets, due to time.

Second factory is closed during the nights. This is where the semi-manual lathes are. Saved program due not having enough time to finish them both.

20/2/14 Carried on making the brackets. I milled out most of the material to leave an island in the middle for reamed hole and rad. Took base thickness to size.

No complications today.

28/2/14 The bottom factory is open so I started on the turning operations. I started making the eye and bracket. Completed all turning operations for both apart from the support bracket which needs to be threaded.

Due to not having a chasing tip which is small enough to chase an internal thread for a M18 thread I have to get the CNC mills to thread-mill the thread.

14/3/14

Carried on with turning operations. Turned

Due to length had to turn component in 2 operations, which unfortunately left a witness mark in the

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support arm. middle of the diameter.

17/3/14 CNC mills scraped support bracket. Threaded M18x 1.25 not M18x 1.5 will have to remake.

4/04/14 Remake of support bracket and finished off eye and support arm

No complications

12/04/14 Materials for rack arms and rack support still not in. Have to wait until boss has returned from holiday to enquire.

25/04/14

Finished off all remaining parts. Made bush and finished brackets.

No complications

27/04/14

Welded rack support and rack bars to each other. Also assembled rest of the components.

No complications

4/05/14 No complications

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Finished assembling and heated up bars to be bent. Sprayed painted product for protection.

Presentation

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Here are a few Slides from my presentatio

n.

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Evaluation

After doing much testing, I have found that my product meets several points of my specification. Using a diverse amount of surfboards, I found that the rack will always go up and come back down without any assistance from me or someone else. Using a compressor I can regulate the speed of how the rack goes up, by changing the pressure of the air by either raising it or lowering it. I did change the pneumatics circuit to a simpler design. I used a vent valve which is turned off when the rack is up and when I want the rack to lower I open the valve and slowly let the air out; this will then slowly lower the rack down with the surfboards. I can also control the speed of how the rack lowers by how much I open the valve, the less I open the valve the slower the air is released so the slower the rack will move. Then using the compressor I raised the rack back up. I found that it didn’t matter what kind of surfboard I used, the rack always worked; even for longer surfboards the rack worked, I did find it harder to put boards longer than 9ft on the rack because of the length, but I designed the rack specifically for surfboards from 3-8ft, which it works perfectly for.

My calculations for the force needing to lift the rack were not too far off. After doing a test of different pressures I found that anything over the 1 bar/ 99 KPa was enough force to take the surfboards and rack up. Although the force below that figure did lift the rack up, it was too slow for what I needed and you could tell it was struggling. It does help a lot that surfboards weigh so little, which makes the pressure/force needed, not to change too much, by only needing the compressor to stay just over 1 Bar. This was due to me finding out with the tests I performed, realised that in this area the rack wasn’t too fast or too slow.

In my specification (see page 5), I wanted my product to be: easy to install, lightweight and sturdy, to be placed in any room, easy access for getting surfboards, long life, decorative, security for the surfboards, cost and time.

Easy to install; well most of the parts are easy to install; the only problem I have is being able to assemble the rack arms but also having the curved ends. When I put the product together I had to bend the bars after assembling the arm to the conjoining part. This made it quite difficult to bend the arms; due to the length of the arm and having the conjoining part being in the way. Though I welded the support bars to the rack arms to save cost and machining time; it wouldn’t be easy for people that don’t know how to weld, like myself. So I will have to come up with a simpler way of supporting the racks and joining them together, without changing the design too much. For future reference I have come up with an idea of how anyone could put the rack together much easier then I had to. It does mean more machining time but it would be a much better design and it will look like something people would buy. To get round the welding problem, I have thought of machining slots into the arm racks and then I can assemble the support bars into the slot in the arm rack. By using either a split pin or a bolt, I can secure together and align the parts more precisely. This idea won’t just make it easier to assemble; but will also make the product look more presentable. The other idea is the problem with assembling the bars with the curved ends. To get round this problem, I have come with the idea of having the bars in two parts. This means that one end of the bar will

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have a threaded shaft and the other end will have a threaded hole. You can then slot the end with the threaded hole into the Bush or Eye and then screw in the other end of the bar. Then keeping to the same idea as above, I use the pins for positioning to make sure the arms are equally apart.

Lightweight And Sturdy; the product is very sturdy but quite heavy. I haven’t weighed it because of how big the whole product is, but I can lift it and move it around, even though it’s quite awkward to move due to its size, I only need it to be lightweight so it doesn’t fall of the ceiling when fastened to it. The weight of it is mainly due to me making the parts out of mild steel; ideally I would have made it out of aluminium because of its lightweight factors and the shelf life it has due to its protective oxide film. Talking about shelf life, to help the mild steel from rust, I did paint the rack with Hammerite paint which protects materials from rust. Although it’s only a temporary prevention, it can last up to a few years, it does mean that the paint will peel off but it also gives it the opportunity to come in different colours. If I did use aluminium, then I would still have to use paint to protect it from the salt; even though it is still protected more than steel. To help the aluminium, I could either paint the material or anodise. Anodise is more expensive but it looks more professional and it lasts longer.

Positioning and Accessibility; after seeing the design assembled, I’ve realised that the rack is too big to be put in a room and when the ram has extended its does add half a meter, putting the rack quite close to the floor. The best place for this rack is in the garage. It may be too big to be put in a room but I feel that a rack in the garage is needed more than a rack in a room. Most people store surfboards in the garage then in the house. Also a ceiling in a house is much lower than a ceiling in a garage, giving the garage more purpose for the rack to go there.

Decorative; once painted the rack looks more presentable, without painting it, the look of the mild steel didn’t make it very appealing. Now I’ve come to the conclusion that the rack is too big to live in a house, I still feel that it needs to look presentable, so I have painted the rack and it does look more decorative.

Security; after testing the product on many different surfboards, I have found that the surfboards sit on the rack very securely. With the curved ends on the bars, it helps the surfboards from falling off the edge when lowering and rising the rack. As long as the pressure isn’t too high on the compressor, there is no way the surfboards can be damaged or fall off the rack. I feel that the surfboards are very secure on this rack.

Cost; It’s quite hard for me to tell you how much this project costs due to me managing to get everything for free or borrowed; like the compressor, which I borrowed from my friend for a few days so I can test out the different pressures that would suit my project. The material was given to me by work, I used my dad’s welder and got a pneumatic ram from the scrap which worked perfectly. Unfortunately I couldn’t get the SolidWorks to give me a quote on how much the machining cost would be; it wouldn’t allow me to choose the material but talking to my boss from work, he says that the machining cost would be less than £100 and the material would cost less than that. In my costing figure I wanted it too cost less than £150, I feel the figure I aimed for, would have been too low, especially for the material I have used.

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Although I used a much cheaper material (low carbon steel) than aluminium, I believe that it has made it more expensive in machining cost. The time to make the parts with steel has raised the price, if I had it made in a factory by someone else.

Time; has been my Achilles heel. I found it very hard to be able to use a machine in my own time when free. Due to me having to make the parts of my project at work, it means that I need to wait for the machines I needed to be free and empty from a job. This was quite hard due to me only having a few hours in the evening, after work and a Friday. I wanted the construction part of my project to last no longer than a month and a week. I ended up taking much longer than that, I ended up taking about 3 months to machine and assemble. I still feel that my planning wasn’t at fault; it was just unfortunate that my work would only allow me to machine the parts for my project in my own time. I don’t blame work, seems they allowed me to have the material for free; it is just the way a small business works. It was very hard to predict as well, when I would be able to use the machine, most of the time I would only find out the day before or even the night before. This made it much harder to plan what to do. For future reference, I feel it would have been easier and quicker just to pay for work to machine the parts; it would have been made within a few weeks.

Although I have successfully made a moving rack, there are still a lot more improvements that can be done, like an easier way off assembling the rack and a quieter and efficient way of moving the rack up and down. If I was trying to put this product on the market, making this prototype would have been a great opportunity to perfect the product for a more commercial use. At the moment my mechanical design is way too expensive to sell on the market, but it has left me with my own unique rack.

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Final Conclusion

After evaluating my project on all of the specifications, I conclude that my project as a whole was a success. I did encounter a few hic-cups on the way, which were; having the machines at work being free during my own time, scraping a job by putting the wrong internal thread, witness marks from poor planning of material, communication with boss about delivery of materials and bending the bars after the welding which made it harder. So even though I do have a few areas that need improving, the rack has come out a success. My dad has seen the rack working and I know that I need more people to have a look and get their feedback asking them what they think and how they would improve or change it. This would be a better way of being able to take the project to the next phase.

I found out that using a compressor would not be the best of designs to use for a commercial product. Is the compressor too big and too loud for a surfboard rack? Maybe it would be easier to stay with the conventional one. To be able to sell this product on the market, I would have to find a way of making a mechanical design that was cheap enough to sell.

From my introduction I talked about making a working mechanical project. To give my project a mechanical edge, I decided from three different mechanical components and chose the one I felt was best for my project, but was it the best component to use? Was using a compressor and pneumatic circuits the best way to achieve my goal in making a mechanical surfboard rack? I wouldn’t be able to answer that question fully because I have only chosen that component due to doing some research online and working out a few equations. Maybe I should have done some of my own practical research? Another question, was this the best idea I could have come up with? Well it definitely fitted the specifications for the project by having a mechanical component but was it the best one for me? Did I chose it out of a reason for myself or because it best met the criteria? It does tick a lot of the boxes but was it a too big a task to do in the short period of time?

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