How long to design new products?
How long to design new products?
To give a little background, I am part of a small design team that designs accessories and add-ons for heavy equipment. This could be anything from designing a hydraulically actuated implement to creating a special guard to protect the machine during off-road use. We typically spend anywhere from 1-3 months creating a design(including FEA) but our real issue seems to be outside of engineering. It takes around 1-3 weeks for our purchasing department to process a prototype order,1-4 weeks for quotes, anywhere from 2-6 months to get prototypes, another 1-4 weeks to get through quality inspections, and another 1-2 weeks to get released to our testing department.
After we finally receive parts, our testing department will run testing on the piece of equipment until we reach the full design life of the parts (while also collecting strain, acceleration, and pressure data). That means if it is rated for 500 hours, we will run for the full 500 hours which can take around 16 weeks to finish.
The two main issues here is that it is taking us around 31 weeks to go from concept to prototype and another 16 weeks to finish testing. When you add in design review meetings, documenting design issues, and getting manager approvals for each step of our PLM process, we are usually running over 1 year to finish even a simple project.
Here are some of the questions I have for others mechanical engineers that design welded assemblies and mechanisms:
1. How long does it usually take you to get fabricated parts? My team is good at designing for low volume so we utilize a lot of tab and slot to reduce tooling, minimize bends, and minimize welding. In my mind it shouldn't take 6 months to get most of the parts we order since I could build them in my garage in a week.
2. Does your company have a policy that mass production parts must be produced by the same supplier that creates the prototype parts? In my opinion, this shouldn't be necessary both suppliers can meet the drawing and the design is correct.
3. Does your company require full life testing or do you do some kind of accelerated testing? We do fairly detailed FEA of all our different loading conditions and the loading conditions are based on previous testing. My feeling is that we design way too close to our target life which is the reason we need to do full testing. I also believe that increasing material and safety factors would be much cheaper than running all the tests (the managers see otherwise).
4. Does your company do 100% inspection of prototype parts or do they just check key features and release them for testing? Currently our QC department does 100% inspections including all of the child parts. When you have a fabrication that is welded of several parts, this can be extremely time consuming even with a Faro arm.
5. Does your company increase complexity of a part just to reduce material? My company has the mentality that reducing material reduces cost but I know this isn't true. I would rather increase material or use a higher strength steel than add lots of gussets or extra bending steps.
6. Does your company avoid the use of loctite? One of the biggest design issues we have is loosening bolts due to painted surfaces. Over time the paint wears away and the clamp forces will reduce slightly. When this is coupled with the fact that we insist on using spring lock washers, everything gets looser faster and we require more bolts or more testing. At my previous job we used loctite on pretty much all the fasteners and never had issue of loosening bolts even after thousands of hours.
Thanks for any feedback you can provide!