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Monday, 22 April 2013

Designers can't just think about themselves!


   When I produce a design at work I have many people to think about. Firstly the client, will they understand the design and recognise any benefits within it. Drawings for a client proposal may differ greatly from the drawings I produce for manufacture. A design for a client may have rendered images showing a more realistic view of the finished product. I may only include overall dimensions of the design. Descriptive comment within the drawing maybe more explanatory of the design. A client proposal must be clear and will be visually much different from the more technical drawings produced for manufacture. 

   Once a design has been signed off by a client another set of drawings is needed for manufacture. While rendered images look great they do not hold the correct information for our factory to make a component. There are several different people along the line of production and I must think about their individual processes and make sure the relevant information they will need is clear.

   Often the first process is the laser cutting of the flat part profiles from a sheet of material. For our laser operators I need to mark the material on stock to be used in manufacture. If there is any etching I must point this out. If the material is sensitive to poor handling I must make sure they are aware of this. They will also require the material specification. We work with various grades of steel and alloys; 403,304 and 316 stainless steel.  6082 and 1050 aluminium. CR4, S275 and S355 steel. This information must be clearly described on production drawings or the incorrect material may be used making for a costly mistake. De-burring requirements must be clearly stated and on the actual Laser nest we make sure the operators are aware of any changes to what we recognise as a standard nest. For instance we normally work with a 10mm minimum border around the edge of sheet steel. This can be reduced to 1mm but the laser must be switched to accurate sheet edge detection. The laser will take longer to initiate but as you might have guessed is more accurate on initial sheet recognition and we can squeeze an extra part on. If this is not pointed out it could lead to loss of parts.

    The second group of people I may have to consider when producing drawings are the press brake operators. Do my drawings have all the dimensions they need? Fold line dimensions and bend extents. Overall dimensions and information on the bend radius used so they can match this with tooling in order to produce the piece correctly. Which side is the good side and any relevant tolerances they are required to work to.

   The third set is the fabricators. Here I must detail any welding criteria. If it’s a stitch weld how long are the stitches and at what interval. Maybe the unit needs to be gas tight, maybe no welds are to be visible from one side. Should the fabricator use TIG welding or will a faster MIG weld be sufficient. Again what tolerances are they to work too? Can we laser etch any components to make construction easier?  Will the fabricator require a separate JIG to be made for a job? Are there any holes to be tapped out? If so what thread and to what depth?  Countersinking all these details must be clear or the fabricators will come knocking on the design office door. If in doubt as a designer ask the fabricator. It is easy to draw on 3D programs but it can be much more difficult or even impossible to actually make the component the way it has been designed.
  
  The fourth group are the powder coating people. Colour requirements need to be included, if a specific RAL colour is to be used this needs to be clear along with the finish, satin or gloss. Smooth or textured. Are there any holes or threads that need to be masked up prior to coating? Once coated, should the product be wrapped or palletised for delivery?

   In my design role I feel it is necessary to understand manufacturing processes. If a design is created in a way that streamlines these processes it already has an edge on cost. Working in design is challenging but very rewarding. I have many people to consider whilst carrying out my daily duties, but the more I consider them the more respect I earn and the smoother a job will run. My goals with each contract completed are a satisfied customer and a happy workforce and with careful consideration of all the parties involved this can be achieved.



  
    

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