'Welding' polycarbonate?

[pcatterall]

Watching a car repair video yesterday and a guy was repairing a plastic body panel ( is that stuff polycarbonate?) He was attaching some broken brackets. He was using what I took to be a standard soldering iron and some plastic scraps.
I guess that stuff around our boats will use similar plastics so it would be interesting/useful to know which common plastics around our boats can be repaired and to learn any techniques.

 

[Stemar]

It's a thermoplastic, so it should be possible. A bit above my skill level, though. My efforts with plastic usually end up with saggy work, chicken poop welding and burnt bits.

 

[Plum]

Watching a car repair video yesterday and a guy was repairing a plastic body panel ( is that stuff polycarbonate?) He was attaching some broken brackets. He was using what I took to be a standard soldering iron and some plastic scraps.
I guess that stuff around our boats will use similar plastics so it would be interesting/useful to know which common plastics around our boats can be repaired and to learn any techniques.

It could be a modified polycarbonate or even a high strength polypropylene but either way, as Stemar said, if its a thermoplastic then yes, in theory. I've repaired a small hole in a pvc fender using a soldering iron and some white pvc stripped from electrical cable insulation. A messy looking repair but still holding pressure after 2 years.

Www.solocoastalsailing.co.uk

 

[Graham376]

Car Plastic — 4 Varieties Used In The Automotive Industry (acplasticsinc.com)

 

[MystyBlue2]

Soldering iron and cable ties as the "Filler rod" works a treat. Takes some practice but absolutely do-able and fun too

 

[duncan99210]

You need to use the same plastic as the base material as your “welding rod” otherwise it won’t bond properly (or at all). I had a split in my water tank and tried welding but couldn‘t get the weld to bond as I didn’t have the right plastic to use. I then repaired the neck of my outboard motor fuel tank by trimming a small amount of plastic off the mounting lugs and using that as the welding material. Not pretty but still working 4 years later.
Searching for plastic welding on eBay or Amazon will find lots of kits for doing plastic welding at not overly large sums of money.
I’m not at all sure, however, if polycarbonate is up for being welded. I’ve bent Perspex by heating it gently, bending and h9lding until it cools in the new shape but never tried the same trick with polycarbonate.

 

[rotrax]

I had a back handed compliment about my Oxy Acetylene welding once. Back in the late 70's, when I was a young man.

" #### me! You have done it! I recon you could weld Shit to Perspex! "

The bracket, a flimsy thing meant to hold a racing motorcycles streamling clear of the bodywork, lasted six laps around the TT course in the IOM.

 

[Tranona]

Whilst welding may be good for some jobs such as repairing splits and cracks in thermoplastics, an adhesive is much better for attaching things like brackets. This gives a good explanation of the products available for polycarbonate
acmeplastics.com/content/which-glues-work-for-polycarbonate-plastic/#:~:text=Epoxide%20glue%2C%20also%20known%20as,polycarbonate%20to%20materials%20like%20ceramic.

 

[Dan Tribe]

I saw a guy at a boat show making Tek Tanks HDPE fuel tanks.
He made it look so easy I thought I could do it.
WRONG! I made a lovely pig's ear. Luckily I was practising with some offcuts.

 

[TLouth7]

For rigid plastics superglue is normally the way forward. You can also solvent weld most plastics (e.g polycarbonate, acrylic, ABS, polystyrene).

 

[Mister E]

A gas powered Hot Knife is a better tool than a soldering Iron (cheaper than electric).
These things are really intended for cutting ropes, so really useful as well.

 

[TonyMS]

I've welded PC successfully using a hot air gun. Not pretty, but strong enough

 

[penberth3]

You need to use the same plastic as the base material as your “welding rod” otherwise it won’t bond properly (or at all). I had a split in my water tank and tried welding but couldn‘t get the weld to bond as I didn’t have the right plastic to use.......

Also remove the dirty weathered surface - abrasive paper does the job.

 

[DanTribe]

I've welded PC successfully using a hot air gun. Not pretty, but strong enough

That used to be a put down on building sites. If a craftsman did a less than perfect job, someone was bound to say
"I bet that's strong though"

 

[billcole]

One combination technique is to use glue, but reinforce the repair by laying stainless steel paperclips across the break and then melting them into the plastic parts.