Insert vs Overmolded Grommets on an Automotive Sensor Cable??

[Porsche356supersport]

During some recent competitor sample evaluation we've noticed our competitors are overmoulding grommets and fastners onto the wire harness of a sensor. We did some investigation inhouse regarding the cost benefit of inserting the grommet (using a waffle machine) vs overmolding the grommet/fasteners. Our determination was that inserting the grommet was still the most cost effective. The basis we used for the calculation was three seperate overmold stations. I am just wondering if we missed a trick here? Is it possible to use a shuttle table to synchronouosly mold three to four components onto the harness at once? Typically these harnesses are up to 1.5M long....we had thought about a system where the cable could be feed off a roll, pulled into the mold press, overmolded with components and then cut to length. Is this a dream or is there equipment on the market that can handle this type of operation? In the end I am wondering if people can give some feedback on why overmolded grommets/fastners are being used. The benefits for positioning, quality of seal and retention are clear but does it justify the cost?.....and yes this is a high volume production scenario.

[RWOLFEJR]

....we had thought about a system where the cable could be feed off a roll, pulled into the mold press, overmolded with components and then cut to length. Is this a dream or is there equipment on the market that can handle this type of operation?
.....
In the end I am wondering if people can give some feedback on why overmolded grommets/fastners are being used. The benefits for positioning, quality of seal and retention are clear but does it justify the cost?.....and yes this is a high volume production scenario.

You'd need to first convince me that "positioning, quality of seal and retention" aren't important or justification in itself... Then a person would need to be shown the details of how one method saves money over the other. Then... If the process that was discussed earlier on for going with over molding wasn't as cost effective as inserts, then design equipment that will produce the assembly in a more cost effective way. As you say... "high volume production"... makes it easy to justify equipment that will improve product and reduce costs... increase profit.

That's the fun part... Figuring out how you're gonna bring the pieces together quick and slick...! While designing this you'll need to consider the possibility of needing to incorporated changes or different assembly designs into your new gadgetry.

Good Luck!
Bob

[Kelly_Bramble]

You'd need to first convince me that "positioning, quality of seal and retention" aren't important or justification in itself...

That was the first thought I had!!

[PinkertonD]

Just tossing in my two-cents worth. Over molded to me makes more sense.

It presents a better seal against moisture and dust.

It positions the grommet where it is needed.

It holds the wires for the best possible position regarding vibration, pulling taught etc.

It allows for a neater loom attachment to the host structure.

It also removes the possibility of a grommet being missed out during assembly. Or a grommet that breaks and falls off with handling and packing, unpacking et al.

It looks much more professional like it comes from a company that really knows what it is doing when making this stuff.

It presents a picture to an non technical Purchase Agent as a "finished" product.

Winning a contract is not all about margin. It is about the client's perception of value and professionally finished stuff compared to a loom tossed together by three guys in a garage using grommets from the local hardware store.

Stop looking to save pennies and lose a zillion dollars in contracts. Bloody bean counters are ruining the Engineering world.

I know where I would spend my money for a wiring loom.

Just saying, ya know!