Putting more emphasis on the manufacturability of a design can make the difference between staying afloat or going under for startups or new products. Any conscientious manufacturer does intensive planning before launching a new product, but planning often focuses on design and marketing, rather than the actual manufacturing process, with unanticipated consequences for the budget.
Autotether, Inc. of Chester, CT managed to trim its cost for making a part tenfold by opting for a more economical manufacturing process and consulting with the part maker. The collaboration also netted a lower per-piece cost for the part, despite revisions.
Like many engineering-driven outfits, Autotether suffered no shortage of design innovation. Company founder Anthony Viggiano invented a unique, multifunctional wireless alarm for boating safety applications that protects up to four crewmembers on any motorized watercraft. If someone falls into the water, the communication link between the host receiver (mounted to the boat ignition) and the client sensor (worn by each individual) breaks. Within 1.5 seconds the host device automatically sets off an alarm and switches off the engine.
From Design to Production
As the only active real-time monitoring device offering instant response to a “man overboard” situation, the product’s future looked promising – until the time came to build production quantities, when manufacturing costs threatened to scuttle the profit margin.
“Our device is fairly complex, and so are its components,” says Viggiano. “For the initial prototypes we employed a stock battery contact made of coil spring, but these wouldn’t hold up, so we needed something custom-made.”
After designing a new part, Viggiano set about finding a way to manufacture it, only to encounter a prohibitively high tooling cost.
“Many engineers will design something entirely functional for their product, but that is very difficult to make,” points out Jim Richards, director of sales & marketing for Fourslide Spring and Stamping, Inc. of Bristol, CT, an ISO 9001:2000-certified manufacturer of precision flat springs, metal stampings, contacts, and wire forms. “They get unhappily surprised at the non-recurring expense cost of the tooling required to make the part, as well as the ongoing cost of the part itself — which is often affected by the manufacturing process as much as by the chosen material.”
The Autotether team originally considered the traditional use of a progressive die to make their part.
“We looked at some domestic and off-shore vendors, but they wanted tens of thousands of dollars for a progressive die, way too much for our modest budget,” recalls Viggiano.
The Fourslide Process
Then a project engineer suggested the fourslide manufacturing process. Named for the four tool slides that perform stamping and forming operations, the process begins with a coil of raw material in flat strip form, which is stamped or blanked in the progressive die section of the fourslide machine. The strip then feeds into the forming section, where four tool-carrying slides approach the part from the four cardinal compass points, forming the material around a central tool or mandrel. The setup of the machine cams determines the sequence, timing, and number of tool strikes (see a demo of the process here).
Because the four forming tools are simply tool blocks carried by the slides, they can be machined in much less time, and for a fraction of the cost of complicated power press dies that require actuators within the tool itself to perform the forming functions.
“As opposed to the power press tools we were looking at that ran $40-50,000, the fourslide manufacturing tools came in at 1/10 that amount, just $4-5,000," says Viggiano. “This savings greatly reduced our up-front capital investment.”
Other Benefits of Collaboration
Additional collaboration with the vendor played an equally important part in helping Autotether trim its costs before production.
“We went through several iterations with Tony, as there were extra features that he wanted,” explains Richards. “At first we said, ‘Here’s what it is going to cost, as called out in the design.’ But then we started reviewing it and making suggestions that could save him a lot of money. We ended up compromising so that he got what he wanted from a performance standpoint, but at a greatly reduced tooling cost and with a lower piece price.” Such a consultative approach almost always pays off for any new-product development.
“Oftentimes, a manufacturer will put out an RFQ for a design that is quite doable, but there will be a particular feature on it that may be of minimal value, and the design engineer doesn’t realize that that particular feature will significantly drive up the manufacturing cost,” says Richards. “In other cases, we’ve seen engineers who will do a whole string of calculations on what the deflection of a spring should be, but give little consideration to the manufacturability of it.”
“The better approach is to talk with the part vendor during the design phase,” continues Richards. “And to reduce manufacturing costs even further, the collaboration should extend through the prototype stage, on into production. This generally results in higher quality and better functionality at a lower cost.”
“We had to make a couple of revisions, and the Fourslide guys were right on top of it,” says Viggiano. “It turns out it wasn't enough to get alarmed about; only around $1,000. If we had a progressive die, a change would be more like $10,000."