Designed to Fail

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In this age of high tech, computer based design. A growing problem is becoming obvious to us here at Clevedon. As you know, whilst we do some very clever cold forgings and self-piercing products, our main business is based on the humble rivet. Solid Semi-Tubular and Fully tubular rivets. Some of you reading this blog may not even know what these products are or will confuse them with “pop” or other blind rivets

Therein lies one of the problems with modern design techniques. A confluence of two factors, demise of “old style” apprenticeship’s where some of our best engineering talent learned their trade and the rise of the computer savvy, Ipad literate younger generation, many young designers have not been taught some of the most basic, fundamental engineering techniques.

This is not their fault, most CAD systems are great at producing designs drawings. Unfortunately, only certain techniques are included in the various wizards and “look ups” which mean that only certain outcomes will be produced.

Quite often these unintentionally, pre-defined outcomes are very difficult to productionise and more importantly very costly to manufacture.

We have had experience of being told by very well meaning designers that our suggested fixing proposal will not work because their Finite Element Analysis (FEA)testing show that the rivet will fail at a particular load. This despite that fact that in our long history (we began business in 1939), we have never encountered a failure mode of the type the FEA predicted would happen. To prove the point, we undertook practical testing to discover what happens in actual practice. The rivet did not fail.

Drawings  are sent to us where in order to realise the designers dream, the product needs to be turned, milled, drilled, ground etc.  Each operation results in expensive individual set up and run times and thereby the final product is very costly to manufacture, at which point some very innovative designs are dropped because they do not make economic sense to peruse.

Powder printed samples are very good straight off the CAD system, but are incapable of predicting that the whole project will fail due to the lack of basic engineering input at the beginning. The old adage rubbish in, rubbish out, still holds true. All of these very sophisticated, technologically advanced  CAD and FEA systems all have the same fundamental, inherent weaknesses and results in the waste of large amounts of time, money and company resources, to say nothing of the potentially game changing design concepts that never come to fruition.

Here at Clevedon we do not claim to have all the answers but we are very good basic engineers. Having had to fight against overseas competition that has destroyed many good UK engineering companies we do have a very good track record in providing low cost, practical, innovative solutions to seemingly intractable design issues.

For the above reasons we have introduced a “Design Support Agreement” to work with designers to put some of the practical elements back into the design process that don’t come straight out of the can. We have found this has the most beneficial effect when we are involved early on in the design cycle but have also been able to re-engineer designs that have got into difficulty (usually cost difficulties)

Please contact us and ask for Steve Hardeman and we will very soon be able to let you know if we are able to help.