Need some advice on molded plastics and metals...
Need some advice on molded plastics and metals...
(OP)
Hello
I have a question for any engineers skilled in plastics molding or metals. I need to know if it's possible to manufacture a needle-like device that would be 12 to 18 inches in length with a diameter of no more than 3/64th of an inch. The tip would need to be blunt (as opposed to sharp) and the other end would have to have a hole that could accomodate some thread. Can something something like this be made of fexible plastic such as polyethylene and meet those dimensions? Alternatively, could something like that be made of flexible stainless steel? My crude rendering is attached. Any input would be most appreciated!
Jack
I have a question for any engineers skilled in plastics molding or metals. I need to know if it's possible to manufacture a needle-like device that would be 12 to 18 inches in length with a diameter of no more than 3/64th of an inch. The tip would need to be blunt (as opposed to sharp) and the other end would have to have a hole that could accomodate some thread. Can something something like this be made of fexible plastic such as polyethylene and meet those dimensions? Alternatively, could something like that be made of flexible stainless steel? My crude rendering is attached. Any input would be most appreciated!
Jack





RE: Need some advice on molded plastics and metals...
Either way, it's possible, so far, to meet your spec in plastic or metal.
Mike Halloran
Pembroke Pines, FL, USA
RE: Need some advice on molded plastics and metals...
This could be fabr with extruded nylon filament. Cut off tip on a bias like a surgical needle. The hole end could be upset with a simple piercing die. It will look similar to a sewing needle.
RE: Need some advice on molded plastics and metals...
Plas, I hadn't thought of nylon but I'm not an engineer. Ideally, the tip would be as blunt as possible because it's for an application that would be used by kids.
As far as plastic vs. metal is concerned, are there any advantages of one over the other? Also, assuming I was producing several thousand can you give me any sense of what I might be looking at for a per unit cost? Thanks!
Jack
RE: Need some advice on molded plastics and metals...
Plastic will be much more flexible than stainless steel.
The cost will be sensitive to details that you haven't defined yet, but in general the plastic will be cheaper.
Mike Halloran
Pembroke Pines, FL, USA
RE: Need some advice on molded plastics and metals...
Thanks again for the input! I was mistaken when I said the tip would be blunt, it actually needs to be sharp. With that in mind, it seems as though plastic would probably not be the way to go. Would you agree?
Jack
RE: Need some advice on molded plastics and metals...
Mike Halloran
Pembroke Pines, FL, USA
RE: Need some advice on molded plastics and metals...
RE: Need some advice on molded plastics and metals...
Jack
RE: Need some advice on molded plastics and metals...
Ideally I'm looking for something that might be as long as a knitting needle but is has to be MUCH thinner, more like a regular needle. They have to be less than 1/16 inch in diameter.
Jack
RE: Need some advice on molded plastics and metals...
RE: Need some advice on molded plastics and metals...
"Art without engineering is dreaming; Engineering without art is calculating."
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RE: Need some advice on molded plastics and metals...
I really can't exceed 3/64ths on the diameter and have it work.
Mad
Not sure what you're referring to when you say "kink" but the diameter requirement remains. This object which looks as though it would best made of metal, must be able to pass through an opening no wider than 1/16th. For all intents and purposes you could think of it as a VERY long sewing needle, although it would be desirable if it had a bit of flexibility to it.
Jack
RE: Need some advice on molded plastics and metals...
Most of them 'swell' quite a bit where the eye is.
Something like a mattress needle might be close to what you need. http://en.wikipedia.org/wiki/Sewing_needle
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Need some advice on molded plastics and metals...
That sounds a lot like something I just ordered called a "Doll Needle":
http://ww
I think that's probably the longest commercially available needle I'll be able to get. I won't know just how wide it is at the eye until I get my hands on one and put a pair of calipers on it. If it's not too wide I may be able to get it to work...
Jack