Strongest plastic thread
Strongest plastic thread
(OP)
Hello!
I'm searching information on plastic threads, especially on how to optimise the thread to get the maximum tensile force.
Any pointers would be appreciated.
I'm searching information on plastic threads, especially on how to optimise the thread to get the maximum tensile force.
Any pointers would be appreciated.





RE: Strongest plastic thread
E.g. 1-3/4-4 Acme vs 1/4-28UNF.
Mike Halloran
Pembroke Pines, FL, USA
RE: Strongest plastic thread
RE: Strongest plastic thread
I'm still trying to figure out how to use it in a sewing machine; it's so stiff that it doesn't always buckle when the needle backs up to make a loop for the bobbin to jump through. Barred needles help, but not enough.
[ The job is gone, but I'm still trying to solve the problem. All engineers are lunatics that way. ]
Mike Halloran
Pembroke Pines, FL, USA
RE: Strongest plastic thread
RE: Strongest plastic thread
By really hot, I mean in direct contact with cast iron that was glowing red-orange. The stainless thread took that abuse a lot better, but the machines dropped every other stitch, so the seams had to be done twice and looked like crap.
Mike Halloran
Pembroke Pines, FL, USA
RE: Strongest plastic thread
In glass, several yarns are wound together to create balanced yarns. It is not uncommon to find yarns with over 100 miles of filaments per pound of material.
Wes C.
------------------------------
No trees were killed in the sending of this message, but a large number of electrons were terribly inconvenienced.
RE: Strongest plastic thread
RE: Strongest plastic thread
I should have been more specific. I am inquiring about bolt threads, how to make the plastic threads stronger.
RE: Strongest plastic thread
RE: Strongest plastic thread
Larger diameter & finer pitch, maybe rolling the threads instead of molding, use fiber and/or mineral reinforcement
Regards,
Cory
Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips Fora.
RE: Strongest plastic thread
RE: Strongest plastic thread
Using a suitable plastic and getting some sort of fibre reinforcement in there makes the real difference. Icotec use continuous glass and carbon, but short fibre will be quite good as well.
RE: Strongest plastic thread
The "J" in UNJF implies rolled threads. Cut threads are called out as UNF. Plastic threads can be cut though.
I worked at an injection molder when I was in high school, and we produced several types of thermoplastic screw. Some threads were molded. Others were shank only, and the threads were cut with a die.
Wes C.
------------------------------
No trees were killed in the sending of this message, but a large number of electrons were terribly inconvenienced.
RE: Strongest plastic thread
I thought UNJF just meant "controlled root radius" for the male threads, with no real restriction on how the thread is formed. Rolled threads do offer strength improvements on metal fasteners...and I don't know if one can buy UNJF series thread-cutting dies or not.