Bonding metal wire to porous plastic cylinder 2

[Oseania]

I need to bond a thin metal wires into a porous plastic cylinders made from PE or PP. The metal wire should come right out of the side of the cylinder and it should be always at the same position. The cylinder has diameter of 2 mm. The metal wire has diameter of 0.1 mm.

I was thinking of drilling a hole (e.g. with laser) through the cylinder and then welding the wire from the other side to the side of the cylinder. However I don't know how ultrasonic or laser welding works with porous plastics. I can have use different wire forms (e.g. hooks) but the wire should be thightly attached to the cylinder.

Does anyone have experience in joining parts to porous plastics?

 

[MikeHalloran]

You can't weld materials with substantially different melting points, e.g. metal and plastic.

You can't easily bond _anything_ to PE or PP.

Ultrasonics won't work on porous plastic without crushing the porosity out first.

All I can think of is drill one cross hole, insert the wire, then take a turn or six of the wire around the cylinder.

Frankly it sounds like you have painted yourself into a corner. It may be time to start over.




Mike Halloran
Pembroke Pines, FL, USA

 

[Demon3]

Can you crimp a metal fixer on the wire as it emerges from the tube on each side? That would hold it in place.

Chris DeArmitt PhD FRSC CChem

http://www.phantomplastics.com

Consultant to the plastics industry

 

[btrueblood]

Heat the wire and poke it thru the cylinder? As Mike says, it likely won't bond well, if at all, to the cylinder. If, however, it stays hot enough or could be electrically (resistance? induction?) heated, you might be able to press the wire against a hard stop with enough force to cause it to buckle internally within the cylinder, providing some degree of "locking". Might mess up enough internal structure that you lose whatever flow characteristic the porosity is providing, though. Could you insert-mold the wire when the plastic part is molded?

 

[Oseania]

Thank you for all for responding this post. I think that I will try to insert-mold the wire and if that doesn't work then I try metal crimping.

 

[AdamPeszel]

Oseania,
There are two things I would recommend. First, insert molding as previously mentioned, but the wire should have a cross section that changes in the middle, to enhance your holding power.

Second, check out an adhesive. The boys at Lord are typically the first place I go.

Adam