Design & Technology

The Design Process

RainWalker

Client Profile

Answer Questions:

Who?What?When?Where?How?

The client for this design situation is a young man in his early forties who is small in stature and of light build. He dreams about climbing mountains, bush walking and other vigourous outdoor activities but due to health constraints he instead enjoys regular walks to exercise, aid digestion and pray. He is practical person who is prepared to buy quality products that work well and last but he would purchase them when they are on special as he likes to get value for money. He dresses neatly yet conservatively with much of his clothing purchased from the opportunity shop. He often has difficulty buying clothing because of his body shape and would prefer to dress in natural fabrics rather than synthetics.

Client Profile

Design Brief

Outline:

SituationSpecifications

ContraintsConsiderations

Quality

Situation For anyone who walks in the rain it is easy to throw on a coat over what you are wearing and venture out. The problem arises when the water accumulates on the front of the coat and runs down and saturates the front of your legs. What is required are some waterproof pants/leggings/gaiters that are compact, light, quick, easy and safe to put on.

There are a wide variety of people who could use this product for recreational purposes but I am concentrating on the leisure/fitness/pet walkers who want to exercise even if it is raining. The product would be used seasonally when it rains and would market between 50 and 150 dollars.

Specification Constraints- It needs to be waterproof- Durable and hard wearing- It is the correct size- Keeps legs dry- Can be easily and quickly put on and taken off- Cost under $150

Design Brief

SpecificationConsiderations- The types of material that area available. Taking into account weight, flexibility, waterproofness, durability, cost and colours.- How to hold the product up using elastic, a belt, clips or draw string.- How to make them quick, easy and safe to put on and take off using zips or clips.- The products style, shape and colour. - The product does not restrict movement and is comfortable to wear.- That the design keep as much water off the feet as possible.

Quality StatementThe quality of the product will be evident by;- Seams that will be sown neatly, straight and uniformly. - No extra puncture marks in the fabric. - Waterproof tape that is consistently and evenly attached over the seams. - The use of quality zips, buckles, straps and snap buttons.

Design Brief

Evaluation Criteria

Itemize:

CriteriaRating

JustificationProduction

Testing

Evaluation Criteria

Image Board

Sets:

MoodConcepts

Arena

Image Board

Wet, cold, refreshing, dark, restrictive, invigorating, essential, hibernating, life giving, cyclic, seasonal, depressing.

Research

Investigate Different Aspects:

MaterialsStyles and design

Tools and processesTesting materials

FabricsTo maintain the fabrics waterproofness and breathability the garment needs to be properly maintained. As over time the fabrics ability to enable water to bead up and roll off is diminished. When the ultra thin treatment that changes the fabrics surface tension the Durable Water Repellency (DWR) is gone it allows water to be absorbed through the fabric. And although there is a layer of material protecting the breathable membrane its breathability can be reduced by the accumulation of dirt or body oils. Therefore regular maintenance is required to maintain its performance.

The maintenance involves washing the garment in warm water using a pure soap or a specific soap made for breathable waterproof fabrics that will also help restore the garments DWR. Or another way to restore the garments DWR is by applying heat. This can be done by placing the garment in the dryer on a warm setting or by ironing on the lowest steam setting. If due to the age of the garment the DWR is not restored then a spray on DWR treatment can be used.

These waterproof breathable fabrics are very specialised and only used in only a small range of garments for outdoor recreation. None of the garments is manufactured in Australia making it difficult to source the fabric. A company who repairs outdoor recreation garments, ‘Remote Equipment Repairs’ has a few sources to purchase fabric but was only willing to give me one suppliers contact details. It appears form the samples that ‘Recreational Fabrics’ supplied that they have a limited range that may be several years old as it does not include the more recent fabrics now available on the market.

Research

Design and Styles

The pants vary in;● Cut - Tapered or straight legs. ● Construction - One piece elastic waste, draw cord, buckle or zip and button, waterproof zip or

storm flap.● Features - Pockets, half, three quarter or full side leg zips, reflective tape, adjustable ankle tabs,

snow gaiters, thigh venting, stretch knee panels, reinforced ankle and seat areas, articulated knee, zipped fly.

● Colour - Mainly grey or black, some navy blue and brown.● Style - Depends on application. Generally a looser cut for bush walking and a tighter cut for

climbing or skiing.

Research

Pants - MontHydronaut Pro

GaitersGore-Tex

ChapsOil Cloth

Pants-SwiftGore-Tex

Tools and ProcessesThe most important process other than ensuring the quality and fit of the of the garment is to make sure that it is waterproof to keep the wearer dry. Care must be taken in the manufacturing process not to make any unnecessarily holes in the fabric that would allow water through. All stitching seams need to be waterproofed after manufacturing. There are two methods to achieve this. The first is by using a polyurethane sealer that is applied over the seam and cures over several days. This sealer can also be thinned down using a solvent and then pressured into the thread and holes. Or alcohol can be applied to the seam and then the sealer which also makes it more workable. The second method is using a seam sealing tape. It is placed over the seam and then heat and pressure is used to melt the glue to adhere to the fabric . This can be done using a machine to ensure even temperature and pressure or done using a household iron and a little practice.

The types of zips used are also a factor to consider. Again there seems to be two alternatives. The first is using a regular zip and covering it with a flap that is held in place by velcro or snap buttons to make it waterproof. Or by using a waterproof zip (that does not need a flap to cover it) but which is not as flexible as a regular zip. The snap buttons can be fastened using a specific machine or a hammer, block of wood and a little practice. A normal domestic sewing machine can be used to sew the garment together.

Research

Material TestingWaterproofness is measured through a hydrostatic head pressure test. Placing a tube over the fabric or seam then filling it with water until it leaks. The measurement before it leaks is its maximum hydrostatic head. A hydrostatic head rating of 1000mm is equivalent to rain in 56kmph winds. This is the minimum requirement in the United Kingdom for a fabric to be called waterproof.

Waterproof fabrics use different methods to make them waterproof. For example the Gore-Tex fabric uses a microporous membrane with each hole being 20 000 smaller that a drop of water, yet allows water vapour to pass through. Another fabric Sympatex use a closed hydrophilic membrane that contains no holes but stiill draws water away from the body through physiochemical process.

Research

Water vapor passing through the fabric from the inside of the garment while water droplets are repelled on the outside.

Hydrostatic head pressure test with a water filled tube placed over the seam.

Design Development

Document:

IdeasBrainstorming

ConceptsCreativity

Ribs on legs to run water away from feet

Design Development

Tapered cuff to run water off

Full length zip with cover flap

Chaps with full length zip

Knee length zip

Belt and straps to hold up leggings

Waterproof booty to cover foot

Flap held down by snap buttons

Zips covered by flap to keep water out

Rib on bottom of coat to run water away from legs

Design Options

Develop Working Drawings:

DetailedAnnotated

Full length leg zip with snap button fastened cover flap

Design Option 1

Adjustable straps

Curved cuffs to run water away from feet

No inside leg seam required

Seams sealed with waterproof seam tape

Adjustable quick release waist band

Evaluation Criteria

Assess Each Option:

CriteriaRating

Explanation

Evaluation Criteria

Design Option 1

Client Feedback

Discuss Design Options:

ConceptColourShape

FunctionCost

Appeal

Client The client had difficulty coming to a decision as he could see the advantages and disadvantages with all the options. He observed that option 1 had less material, bulk, heat and more freedom around the groin but he was not sure how the straps would work, how they would feel and ride when walking. Option 2 did not have those problems but both the designs having no seat or front could only be used in a limited and specific range of activities. He would not take them bush walking or skiing for example because you could not safely sit down or fall over without the risk of getting wet. The main difference between options 3 and 4 is the length of the zips down the legs.

OthersThe other people who looked over the different design options had some rather well formed views of what they would like in a pair of breathable water proof pants. Firstly they did not like zips and the idea of having to connect the zip together and then zip down the full length of the leg was not appealing at all. It was enough just to have a zip from the knee down. For them it was simpler to have pull on pants rather than get tangled in zips and getting frustrated in trying to do them up. They also would prefer an elastic waist band with a draw string as they thought it would be more comfortable than a buckle and adjustable straps. They were not concerned about the bulk around the groin area with and options 3 and 4 but they did have reservations about option 1 with the straps and how they would feel walking and sitting. They agreed that option 3 and 4 would be more multi purpose and versatile because they had a seat in them. You could use them in the snow for instance.

Client Feedback

Prefered Option

Write Justification:

ConceptColourShape

FunctionCost

Appeal

JustificationThe preferred design is option number 1 as it fulfils all the specifications and achieved the highest score using the Criteria Grid. The reasons for its choice are listed below:

● The design eliminated the need for an inside leg seam thus reducing the potential for leaks.● The simplicity of the design means that it is quick and easy to put on and take off. All that it

required is to click the adjustable waist buckle on, join and zip down each leg, cover the zip with the flap and fasten the snap buttons. To take it off just reverse the process. This can be done with two feet on the ground. Which eliminates the need to try and balance yourself against a wall as you try and pull off your wet pants over your shoes (option 3).

● The materials used; the fabric, buckles, snap buttons, strap, waterproof tape and zips are of the same quality of those used in the garments of the leading brands on the market. All that is required now is to ensure that the workmanship is of the same standard.

● With the design finishing at the top of the legs it eliminates the doubling up of material around the groin and therefore doesn’t restrict movement or generate excess heat. In design options 3 and 4 the wearer would add three layers of fabric over their groin; their trousers, coat and waterproof pants.

● The cuffs at the bottom ot the garment are curved over the foot to run the water coming down the leg away from the feet in an attempt to keep them as dry as possible.

● I was originally thinking of using a 2 ply breathable waterproof fabric because it is more pliable and compact, lighter and drapes better than the 3 ply fabric but I would have had to attach a backing to it to protect the breathable membrane. Instead I settled for the 3 ply breathable waterproof fabric which comes with a protective layer already attached.

Prefered Option

Production Planning

Detailed Working Drawing:

SizesCuts

ShapesMaterials

Specifications

Working Drawing

Prefered Option

Production Planning

Materials List:

ItemMaterialNumber

SizeCost per...Total cost

Materials List

Production Planning

Production Planning

Production Steps:

StepProcessMaterial

EquipmentQualitySafetyTime

Production Steps

Production Planning

Production Planning

Gant Timeline:

Production scheduleTaskTime

Gant Timeline

Production Planning

Production Planning

Risk Assessment:

Specific aspectHazards

Possible injuriesRating risk/injuryControlling risk

Risk Assessment

Production Planning

Concludes

Pre Production Design Process