Undoing ultrasonic welds?
Undoing ultrasonic welds?
(OP)
Is it possible to "unweld" ultrasonic welds on plastics?
I do LED brake light conversions on car tail lights as a sort of hobby, and usually will just use a dremel to cut off the rear part of the tail light to do the conversion, and use epoxy resin to seal afterwards.
I know that some people just use a knife tip on a soldering iron and basicaly cut the rear off.
I heard from a friend today that it's actually possible to unweld the ultrasonic welds that bond the tail light cover to the rear housing, so that you get a clean disassembly. He mentioned something about putting some kind of liquid on the weld and that the housing would separate after a certain amount of time.
Has anyone heard of anything like this?
I do LED brake light conversions on car tail lights as a sort of hobby, and usually will just use a dremel to cut off the rear part of the tail light to do the conversion, and use epoxy resin to seal afterwards.
I know that some people just use a knife tip on a soldering iron and basicaly cut the rear off.
I heard from a friend today that it's actually possible to unweld the ultrasonic welds that bond the tail light cover to the rear housing, so that you get a clean disassembly. He mentioned something about putting some kind of liquid on the weld and that the housing would separate after a certain amount of time.
Has anyone heard of anything like this?






RE: Undoing ultrasonic welds?
If the weld is perfect, the two halves are joined as the materials melt and fuse together as one.
Having said this, the weld will never be perfect and is normally a weak spot that might be more susceptible to being prised apart. Usually the weld is a bit inconsistent and the part mainly breaks on the weld line, but occasionally the break will move away from the weld line and pull some material from either side at random.
I would cut the parts apart with a very sharp serrated knife, then use a cement made of solvent and the same resin as the tail light to glue it together again.
The solvent used will depend on the plastic involved. Most common for the non transparent parts are ABS, PC or PMMA.
Regards
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RE: Undoing ultrasonic welds?
RE: Undoing ultrasonic welds?
Aaron A. Spearin
ASQ CSSBB
Engineering Six-S'$
www.Engineering6ss.com
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RE: Undoing ultrasonic welds?
RE: Undoing ultrasonic welds?
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