Plan of Manufacture 

A ‘Plan of Manufacture’ means choosing the best, safest and most cost-effective method of producing your prototype product; the best / correct materials; and the best way to control the product quality i.e. making sure that parts fit together. A Production Plan or Flow chart is a key part of your / a company’s Quality Assurance and Quality Control (QA / QC) systems, because it documents each stage of manufacture. This enables checks to be made for quality, so each component of the product is made to the same standard. A Production Plan also enables faults to be identified at certain times and provides feedback, so that changes can be made, if necessary. You are making a one-off product (a test prototype) so it is appropriate to try and plan the process of how you will make it. You should also record the evidence of what you have done (through photographs and screenshots) to manufacture your prototype. and then use those photographs and screenshots alongside your Production Plan as a Record of Planning / Record of Manufacture / Diary of Planning / Diary of Manufacture. This could then be used to inform if you were making another.

You need to produce a clear plan that explains how to manufacture your product, within the realistic deadlines you have been set. This involves providing details of how to make the product, taking into account quality and safety requirements. Realistic deadlines are those that are achievable. They should match the making of the product to the time available.

The work that you have already done on development, modelling, prototyping and your final test model should help you to plan. 

Your plan should provide instructions for the stages of designing and making your prototype product. It should be worded ‘what you are going to do next...’. You should identify:

·       The order of assembly of the different components

·       Tools, machines and equipment to be used including hand tools, 3D printers, laser cutters, machines, finishes

·       Construction, component fitting and Assembly processes

·       An approximate time each stage of manufacture / process should take

·       Key stages of manufacture where quality is checked (QA / QC) - FEEDBACK

·       Safety requirements and / or procedures that you will need to take

A typical order of production that you could follow might look like:

Start: Final Design & accurate test foam model > Predefined Process: Model 'parts' and components accurately to size in 3D CAD > Process: research dimensions of external (bought in) components > Process: QA / QC check - have you left tolerances between 'parts' so that they will fit together > Process: Assemble 'parts' in 3D CAD > Decision (Y/N): Virtual Test. Do all 'parts' fit together? > Process: Order 'parts', components and electronics > Predefined Process: Create Working Drawings to be A3 printed for manufacture > Process: Export 'parts' as .stl files for 3D printing / CNC machining > Process: Export 'parts' as .dxf file for laser cutting > Decision (Y/N): QA / QC check - are 'parts' the correct sizes on 3D printing / laser cutting software > Process: print 3D 'parts' on 3D printers > Process: print 3D 'parts' on CNC router > Process: print 2D 'parts' on laser cutter > Preparation: prepare materials for machining / manufacture (Cutting list) > Process: Use A3 working drawing and materials to manufacture 'parts' > Decision (Y/N): Check all 'parts' for imperfections and correct manufacture. Do any need to be remade? > Process or Preparation: Clean up all 'parts' / remove unwanted material / smooth surfaces using files and abrasive papers > Decision (Y/N): Do all 'parts' have a good surface finish? > Predefined Process: 'dry' assemble all 'parts' to check fit. Add purchased / external components and check fit > Decision (Y/N): Do all 'parts' and components fit? > Process or Preparation: Solder electronic components and make circuit. Test circuit works > Preparation: Fine finish all 'parts' using abrasive papers > Process: Finish coat to all 'parts' to highest standard (Spray paint x 3 coats, Oil, Wax, Varnish) > Process: Protective layer to 'parts' (lacquer, varnish) > Decision (Y/N): Do all 'parts' still fit? > Process: Fit all electronic components & inserts to join 'parts' > Predefined Process: Assemble all 'parts' securely > Predefined Process: Test final prototype / product against testing strategy and record results > Decision (Y/N): Does everything work as expected? Analyse & Evaluate > Process: Final Photos > Terminator: Stop.

You will need to name the 'parts' i.e. Side panel, Top, Lid, Speaker etc.

A ‘Record of Manufacture’ can be produced using screenshots & photos (Onshape to 'parts' to finished 'parts' to sprayed (primer) 'parts' to sprayed (final colour) 'parts' to assembled final model).

Methods of Manufacture

You are expected to demonstrate an understanding of the working characteristics of a range of materials and components that are appropriate to the manufacture of your product. Your chosen materials should achieve the performance requirements specified in your production plan (they should do what you want them to do / why you picked that material – it’s properties).

To a certain extent you have already demonstrated understanding of the materials, components and processes needed to manufacture your product. You modelled, prototyped and tested materials, components and processes. You annotated your design ideas and developments. In your planning you should have specified the materials, components and processes required to make your product. 

Although most of your practical work will involve making a ‘one-off’ product, there may be times when two or more identical components will have to be made. Your product will either be a one-off for a client, or a prototype product that could then be manufactured in higher volume i.e. injection moulded. This prototype product will still be a one-off, but it will require a different approach, shown in your Development, since its target market is wider and its manufacture may require different materials or processes to those of a one-off product for a single client.

While making your prototype you will encounter complications such as constraints related to the materials (what you can do with that type of material, the size of the bed of the machine, cost of materials), tools and equipment available to you i.e. only 2 Centre Lathes in Department – limited access. If problems occur with the availability of resources, for example, you may have to change your original choice of materials or adapt the processes you use. If this happens, do not forget to record any changes in your diary / production plan and justify any new choices of materials, components or processes. You should investigate Vacuum Casting for batch production of your prototype as this is the method used by industry to produce a small batch (about 50 – 100) for product testing / consumer testing / consumer reaction. This is done before injection moulding the final product to fully test the design before committing to the cost of tooling for injection moulding (potentially hundreds of thousands of pounds).

Other planning decisions may involve:

·       Reflecting on how easy the product was to manufacture in the time available, if it is necessary to simplify anything or if any special materials or tools are required

·       How were the components manufactured – CADCAM, Hand tools / workshop 

·       Estimating costs of materials, production costs and a possible selling price