Looking for ways of joining metal and plastic

In summary: For do-it-yourself, I have not been able to to get a reliable connection by thermoplastic welding the plastic onto the metal.Please let us know what you come up with.
  • #1
Chandrasekar
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TL;DR Summary
How to join a plastic part with a metal part?
i have a plastic handle and want to join it with a metal body. i can join it with heat stacking method i have find a product who done done that.
is there any other way to join permenently?

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  • #2
I have usually seen either weld-nuts on the metal part with machine screws going thru and holding the handle, or making the plastic part slightly deformable with 'hooks' or 'latches' that fit in cutouts in the metal.

There are also instances of having sheet metal barbs that insert into the plastic. Depending on the ultimate use, the barb may be either molded into the plastic of merely inserted into a preformed slot in the plastic.

For do-it-yourself, I have not been able to to get a reliable connection by thermoplastic welding the plastic onto the metal.

Please let us know what you come up with.

Cheers,
Tom
 
  • #3
Chandrasekar said:
i have a plastic handle and want to join it with a metal body.
What sort of metal is it, stainless steel or maybe aluminium ?
 
  • #4
Chandrasekar said:
i have a plastic handle and want to join it with a metal body.
Are we talking about that mug (?) on the picture?

Based on the picture there should be some metal pieces in the handle and originally it was a metal-metal connection, maybe done with spot welding.

I don't think this can be repaired easily (and, what's more omportant: it won't be any sturdier than before).
What I would do ... well, honestly, I would just buy a clay mug, but to use that one on the picture I see two ways:
- to make two rings of metal strap attached to the old handle and make the mug sit in the rings
- make a complete new handle&rings entirely from some steel wire

Something like these, but more 'engineer way':
shopping
 
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  • #5
Rive said:
I don't think this can be repaired easily (and, what's more important: it won't be any sturdier than before).
Very true.
Do not waste time reattaching an old plastic handle to a metal container.
Plastic becomes brittle with time, it then fails at a progressively lower stress.
Replace the handle with new, or with an improved material.
 
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  • #6
sorry guys, i think i have not given proper question.
it is just a example to understand what i want. what i really want is a way to join a plastic part with a metal part (a hybrid assembly - i think).

Thank you for your concerns.
 
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  • #7
Chandrasekar said:
TL;DR Summary: How to join a plastic part with a metal part?

i have a plastic handle and want to join it with a metal body. i can join it with heat stacking method i have find a product who done done that.
is there any other way to join permanently?

View attachment 323028
this picture is given as an example explain to what i really want.

'I just want a any other method to join a plastic part with a metal part.'
i got two way to join
1. Heat Stacking
2. fasteners
is there any other way?
 
  • #8
Tom.G said:
For do-it-yourself, I have not been able to to get a reliable connection by thermoplastic welding the plastic onto the metal.
Thermoplastic welding and heat stacking are same?
 
  • #9
Spot weld a short, flat headed countersunk screw to the metal.
Mould or drill a hole in the plastic to slide over the screw.
Place some glue in the hole, then press them together.
 
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  • #10
Chandrasekar said:
is there any other way?
Are you looking for something what can be industrialized (like that handle from the picture), or just DIY level will do?

For the letter, as I recall there are some glues which can bond on plastic and metal too. But I would keep those only for places without much stress of any kind.
Synthetic resins (even with some fibers added) may be also do the trick (not just used like a glue but as means of extra mechanical support).
 
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  • #11
Rive said:
Are you looking for something what can be industrialized (like that handle from the picture), or just DIY level will do?
for industrialized level
 
  • #12
Chandrasekar said:
for industrialized level
Yeah, go with a mechanical fastener. Personally, I'd say threaded rod welded to the body, and nuts to hold the handle on.
 
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  • #13
I just did a post on bonding metals with epoxy. Search "Methyl Methacrylate adhesives" There are formulas that are mix compatible with metals and plastic. And their bond is outstanding.
 
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FAQ: Looking for ways of joining metal and plastic

Can metal and plastic be directly bonded together?

Yes, metal and plastic can be directly bonded together using various methods, such as adhesives, mechanical fastening, and thermal bonding. The choice of method depends on the specific materials and application requirements.

What types of adhesives are suitable for bonding metal to plastic?

Epoxy, polyurethane, cyanoacrylate, and acrylic adhesives are commonly used for bonding metal to plastic. These adhesives provide strong bonds and can accommodate the different thermal expansion rates of the two materials.

Is it possible to weld metal to plastic?

No, traditional welding methods are generally not suitable for joining metal to plastic due to their different melting points and material properties. However, techniques like ultrasonic welding and laser welding can be used to join plastic components to metal substrates in specific applications.

What mechanical fastening methods can be used to join metal and plastic?

Mechanical fastening methods such as screws, rivets, and bolts are commonly used to join metal and plastic. Inserts, such as threaded or press-fit inserts, can also be used to provide a secure connection.

How can surface preparation affect the bonding of metal to plastic?

Proper surface preparation is crucial for achieving a strong bond between metal and plastic. This may involve cleaning, roughening, or applying primers to the surfaces to improve adhesion. Ensuring that surfaces are free of contaminants like oils, dust, and oxides is essential for optimal bonding.

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