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Process Notes
Links for further reading:
Process Overview
Step 2 - Requirements.
Step 3 - Information.
Step 4 - Design.
Step 5 - Prototypes.
Step 6 - Production.
Process Notes
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Process Notes - Time, Cost and other Considerations:
Below is a collection of thoughts and notes pertaining to the Product Development Process -- and
particularly the Manufacturing Phases. These notes are in no way definitive and are intended as a
generalization. They come as answers to questions we see often and are given in no particular order.
Please let us know if you have additional questions or comments.
One of the hardest, yet most useful parts of the process is the definition of requirements. If you understand
what is required (including the governmental and customer needs) it is much easier (and cheaper) to design the product
and meet the specifications.
Additionally, if you can somehow get a feel for the quantity that will sell, it is much easier to make decisions
about the way the product is to be designed, and therefor the manufacturing process to use. For instance, if a
product is designed to be molded, and the expected volumes are small (100's), the tooling will be made will be much
different than if the expected volume is high (100,000's).
Factors in the Process that effect Cost:
- Time plays a huge part in the overall cost of a project. If you are on a very tight time table, you will
pay a premium for the "instant attention" from most every vendor you deal with. If the timetable can be extended
a bit, the costs of engineering, tooling, and other things go down. Really, the difference for delivery between
"go as fast as humanly possible" and a "let's just keep things moving" might be only 10% or 20% - but the cost can
easily double. Weigh the factors involved in timing carefully.
- When time is really important, perhaps Time Compression Technologies should be considered. Time
Compression is becoming a buzz word in the prototyping and low(er) volume manufacturing areas. This is really
applying technology toward moving very quickly from design to parts. As an example, a typical injection mold
takes ~12 weeks to make. In time compression arenas (like those provided by Synthesis) that can be drastically
reduced. An example is shown in Slide 7 of our slide show.
We have done several parts for customers where the design through component manufacturing has taken just 2 or 3 weeks
-- from start to finished injection molded parts. There are trade-offs, however, and most have to do with cost.
Basically, you pay much less for the tooling, but more per part, and we can't produce hundreds of thousands of parts
very efficiently. This be what it may, it is the perfect solution in some situations.
- Complexity is another factor in cost. Generally, the more complex a product or the more complex a part,
the more it will cost. Careful design and design optimization can help in reducing the cost of a product.
That is an area where Synthesis can really help.
- Going to the right source for the right information is key in finding the eloquent solution, and thereby reducing
complexity, cost and timing. At Synthesis we completely espouse the concept of working with vendors early in
the process so their input can be fully considered and incorporated into a design. We do not claim to be experts
at everything, but we know how to find the experts and we know how to bring the best input from all the different sources
together. Some people call this Concurrent Engineering, We call it "SYNTHESIS".
Factors in the Process that effect Timing:
- As mentioned above, a good understanding of the product requirements can be the best way to save time.
Just knowing what target to shoot at keeps the team from wandering around and having to "redo" the work. It
also does a lot to keep the team interested and excited.
- Available resources (like money and expertise) play a huge part in overall timing. In many cases, more
money can reduce the time to completion, but it has a diminishing return. All the money and all the experts
in the world can't reduce the time to zero.
- Time compression technologies were discussed above and are a great way to reduce the time required for products
to move into production. This is a great way to shorten time, but usually comes with a price.
- In some cases where timing is the driving force in a project, quality is sacrificed because the issues are not
thought through carefully. I always approach things with an eye of some skepticism when timing is the overall
driving force -- "I need it done right now at any price or not at all!"
- Concurrent engineering is a great way to reduce the time of a project. It also brings together more good
brains which usually make for a better overall project. This approach does not usually carry to the extreme
very well as the management issues can over cloud the benefits when the team gets too big.
Costs involved in certain manufacturing processes: (Highly Generalized!)
There is a huge spectrum in trade-offs for price depending on expected volumes and the up-front tooling costs.
If volumes are low, simple tooling can be used – (which usually means higher piece/part costs). If volumes are
really high, complex and usually very expensive tooling (such as multi-cavity molds or progressive dies) can be made
that will bang out millions of parts at the lowest possible price – and there is a whole spectrum of area in between.
- Plastics:
- Injection Molding: One of the most common processes -- The up-front tooling costs can be high ($10,000
- $100,000 or more) with relatively long lead times (12 weeks typical), while part costs are quite low (from pennies
to a few dollars). This process is especially good for High Volume parts.
Time compression injection molding (discussed above) can significantly reduce the tooling costs and lead time,
but trade for higher part costs.
- Blow Molding and Thermal Forming: These processes are typically very good for lower quantity and larger
(size) parts. They have their place and their trade-offs; and like injection molding, they also have a spectrum
of price trades. One of the biggest trade-offs is the availability of materials – though that is getting better
as time goes on.
One of the key benefits of these processes is the ability to have "closed" parts -- something that can't be done
in injection molding without post processing.
- Rotational Molding: This process is typically for very low quantity parts because of the processing time
involved. Also, the parts have to really meet some specific requirements, but this is a great process for
accomplishing some types of geometry that are not possible with other processes.
- Many Others: There many other processes for plastics. These are just a few of the most common.
- Metals:
- Fabrication: This process can best be described as the "cut and weld" process -- though it is not limited
to that. This is generally an expensive method of getting complex parts made, but with the right tooling
(things like stamping dies) can be one of the least expensive methods of producing metal parts.
- Machining: Usually low (or no) tooling costs, with higher piece prices. Can be used to prototype
things that will eventually be made some other way like casting.
- Casting: Much like injection molding for metal, this process can be used to make very complex parts
fairly cheaply. Variations in this process from sand casting to die casting will vary the cost of tooling,
affect lead times and change part prices. This process is typically used for parts of greater complexity.
- Lots more: There are literally thousands of ways to bend, form, cast, machine or otherwise shape metal,
and the choice of processes is entirely dependent on the individual situation.
- Others:
We have listed above some of the most common processes with respect to metal and plastic. These
cover some of the areas where we get the most questions. There are, of course, hundreds of processes for these
and other media like wood, glass, foam, etc.. It is not our intent to document or even start to pretend we are
experts in all those fields. However, we know experts that can get us to the right point.
For more information about the production process and how it may apply to your particular product, please
give us a call.
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