Ultrasonic Welding Question 3

[MikeRCS]

I am very unfamiliar with Ultrasonic Welding of plastics and I was wondering if it is suitable for an application I have. I want to run wire through a flat piece of plastic. I am curious to find out if it is possible to sandwich the wire between two pieces of plastic and ultrasonically weld them together with the wire running through the weld. If so, would this weld make a hermetic seal around the wire? Can it be done with insulated wire? Again, I have no experience with ultrasonic welding and any advice would be helpful.

 

[Demon3]

I have limited experience with ultrasonic and vibration welding. They are the same thing only using different frequency and amplitude of motion.

I think your concept is possible using those technologies.

Chris DeArmitt PhD FRSC CChem

http://www.phantomplastics.com

Consultant to the plastics industry

 

[MikeHalloran]

It depends greatly on the design of the two pieces of plastic; there's a limit to the depth of plastic through which ultrasonics will work.

Given reasonable part design, you may get a decent bond over solid wire insulated with varnish.

I would not expect success with stranded wire or thick insulation.


Mike Halloran
Pembroke Pines, FL, USA

 

[Demon3]

Listen to Mike over me. Sounds like he has more hands-on experience in this area.

Chris DeArmitt PhD FRSC CChem

http://www.phantomplastics.com

Consultant to the plastics industry

 

[MikeHalloran]

I don't know first-hand how ultrasonic assembly works in production; I've never gotten it that far, despite expenditure of considerable money and time, on more than one occasion. I learn slowly, but I do learn.

Beware the sales people.



Mike Halloran
Pembroke Pines, FL, USA

 

[MikeRCS]

I am planning on using 2 sheets of plastic (material undetermined) about 1 wide by 2" long. Run insulated solid 10 mil wire sandwiched in between the plastic sheets. The insulation will be removed from the wire and exposed as it comes out of the bottom of the sheets, Loop around and back in between the two sheets where it will be insulated again then run out the top of the two sheets. The two sheets will need to be fused together so that the wire is sealed inside the plastic. Air and liquid tight.

And I know salesmen well... A salesman can do anything. So he says.

And thanks for your help guys.

 

[patprimmer]

Ultrasonic welding is a bit of a black art.

Some plastics respond better than others.

The design of the joint matters a lot.

If you intend just laying the wire between two flat sheets I doubt you will have real success.

A grove for the wire to run would help.

Small ridges running alongside the grove would help as it concentrates the energy to the area you want it and provides extra melted material at the joint.

Using the same material as the insulation has obvious advantages, or at least a compatible material.

I don't have lists of such.

Regards
Pat
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[Pud]

As Pat says - black art - very black - your best bet is to talk to your local ultrasonic welding kit suppliers. From the brief description, it may be ok (Although if your 10 mil is equal to my 10mm, you will need some serious power!)

Cheers
H

http://www.tynevalleyplastics.co.uk

 

[patprimmer]

Harry

I think 10mil is American code for 0.010" maybe. ;-)

Regards
Pat
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[MacGyverS2000]

When I learned they could fuse two pieces of wood together with nothing but friction, I figured anything is possible with plastic ;-)

Dan - Owner

http://www.Hi-TecDesigns.com

 

[ornerynorsk]

You didn't mention what kind of plastic. It is my understanding that not all plastics can be UW'd. At all, let alone with marginal results. I've heard that nylons, polycarbonates, and the olefins inparticular are difficult, if not impossible.

 

[patprimmer]

I have welded both Nylon and PC with good results

Regards
Pat
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[ornerynorsk]

Thanks for that, Pat. Our vendor is obviously not up snuff, then. We work with mostly unfilled toughened 6/6 and 33% glass 6/6. How does the glass fill affect UW?

Thanks again.

 

[patprimmer]

It makes it more difficult but it can be done.

Also I have only done it with type 6. type 6.6 will be slightly more difficult.

Sunbeam vibration welded their 35% gf66 water tanks for their steam and dry irons back in the late 70s early 80s.

The example I have done is a yacht floating winch handle. It has quite a few designs and brand names. Titan and Lewmar are two names it's sold as. You should be able to see them at any ships chandeliers anywhere in the world.

It is best welded within a few hours of moulding.

If moulded days later the parts need to be dried first.

The PC I have welded was 10% GF for the top of a surf board finbox

Regards
Pat
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