design strategy for tweezers

Well, to start with do you have an image of what it looks like, say a napkin sketch or something? What mfg process will you use to make it?

snipped-for-privacy@hotmail.com wrote in news:1113661462.995971.185060 @o13g2000cwo.googlegroups.com:

The plastic tweezers will be molded and right now I believe they will look similar (though not exactly) to tweezers you'd find thru McMaster-Carr.

Thanks in advance, MT

matt wrote:

various

Do they have to be shown open and closed?

A variable cross secti> The plastic tweezers will be molded and right now I believe they will

They should be shown in an open configuration.

snipped-for-privacy@hotmail.com wrote in news:1113747195.298292.298890 @o13g2000cwo.googlegroups.com:

Are you constrained as to how complex the mold can be? If so, you will need to design the part so it can be pulled out of the mold easily with only two sides of the mold. With plastics, you can do almost anything you can afford. To be a good plastic part designer, you really have to have an understanding of how molds are built and work.

For most of the tweezers I've seen, I would probably use a sweep, with some additional features to shape the ends. It would be a shame to simply recreate a metal tweezer with plastic, since there is so much more you can do with plastics. Did your product development or marketing dept give you any sort of design criteria for the new product?

I have designed a number of plastic replacements for metal, and indeed the design must be reconsidered almost from square one to take into account the exact end need of the product.

Plastic is just so much more flexible than steel or aluminum, that extra care must be taken to design the right amount of stiffness for the job, and acknowledge the limited pinching ability of jaws in plastic and the nature of thin jaws to deform due to both contact pressures on the nibs and from finger actuation pressure.

Tweezers are simple, but I have seen plastic tweezers in both industrial and medical applications that basically suck.

Bo

Think about how you are going to mold them. Where do you want the parting line? How much draft do you need? Are there areas that can't have any draft? Where do you want the gate? How will you eject them?

The simplest approach would seem to be to extrude a profile, with or without draft, then cut the plan view. Does that work well with the answers to the questions above?

Jerry Steiger Tripod Data Systems "take the garbage out, dear"