Anybody do plastic welding ?

[BillK]

Hey guys,

The coolant reservoir on my Wife's 84 Riviera has a small crack and has been dripping. New one simply not available. I could probably rough it up and try some type of "glue" but my experience has been that there really is nothing that sticks real good to the white plastic material these tanks are made out of. So I was thinking of trying one of the hot air type of plastic welders ?

Anyone have any experience with these ? Harbor Fright has one but it has quite a few lousy reviews as far as not lasting very long. Seems like when it works it works good.

Any thoughts on the entire subject would be appreciated. There have been a few times in the past that it would have come in handy on other projects too.

Thanks,

 

[Firebrick43]

I have a steibel digital heat gun with the welding tips that works pretty well, much better than the horror freight unit I started with.

Need to get my 400 gallon indirect water heater tank welded up

 

[Qualitytools]

I have had good luck with using a combination of backing soda and super glue, there are videos of it being used and it is amazing how well it holds. Try it out or check it out and give us your feedback.

 

[subarub4]

Funny I just brought one of these last week from Amazon... I used it on something small but I need to fix the fairing on my bike

https://www.amazon.com/dp/B0BB9DTN78/?tag=atomicindus08-20

 

[Nvrplzd]

While a plastic welding technique would be the best long term solution, there exist many universal coolant reservoirs.. so that could be an option for you as well unless you are trying to maintain 100% OEM parts

 

[BillK]

Funny I just brought one of these last week from Amazon... I used it on something small but I need to fix the fairing on my bike

https://www.amazon.com/dp/B0BB9DTN78/?tag=atomicindus08-20

Thats the type that just melts the plastic together. You can do that with a soldering iron or gun. Really does not work that great, I have done it in the past.

 

[Buckaroo5]

This is a good resource on fixing plastic components. Indicates how to identify different types of plastic and methods for welding, etc.....

 

[dnschmidt]

Might want to consult a bodyshop that has the Polyvance system. They weld up bumper covers all day. You might want to check out the Polyvance website as they are the kings of plastic welding.

 

[WWheeler]

I have two cheap plastic welding kits bought off ebay straight from the PRC, that I've only used once so far to fix a mangled ABS under engine splash tray or whatever it's called (a plastic excuse for a skid plate) for a late 90s Ranger that after what my boy says was a possum strike was dragging all the way home. Using both kits together they worked rather well for that repair. We got it back up in place and seemed to be very strong which is all I was hoping for.

One is the kind that heats up little staples that you melt/bury into the plastic and snip off after it cools (best used on the backside or side most out of view) and the other is an iron for melting additional plastic and screen/mesh if you want and spreading/smearing it around and smoothing it out. I think together I paid about $45-$50 in all. The only salvage yard around that said they had one wanted about that much for it and when we got all the way there it wasn't even close to the right one, so fixing the mangled one became plan B. In hindsight I'm glad because now I've got these for if/when I need them and a little experience with them goes a long way. I'm glad my trial run was for something out of sight.


most

 

[bonneyman]

I know how frustrating those things can be. The wife's 2002 Century had an old tank so stained that you couldn't read the level accurately. I tried cleaning it several ways but it really didn't improve, so I had to find a replacement. Found a surprising number of places selling those white plastic reservoirs. I know you need one 20 years older but might be possible - or maybe you could retrofit something close? I did a 5 minute search and found these guys.

https://www.opgi.com/cooling-heating/overflow-tanks-catch-cans/coolant-overflow-tank/tank-coolant-overflow-78-88-el-caminomalibumonte-carlo-l240901.html

 

[BillK]

I have two cheap plastic welding kits bought off ebay straight from the PRC, that I've only used once so far to fix a mangled ABS under engine splash tray or whatever it's called (a plastic excuse for a skid plate) for a late 90s Ranger that after what my boy says was a possum strike was dragging all the way home. Using both kits together they worked rather well for that repair. We got it back up in place and seemed to be very strong which is all I was hoping for.

One is the kind that heats up little staples that you melt/bury into the plastic and snip off after it cools

I saw that but I dont think it will work on something that needs to hold liquid.

 

[BillK]

I know how frustrating those things can be. The wife's 2002 Century had an old tank so stained that you couldn't read the level accurately. I tried cleaning it several ways but it really didn't improve, so I had to find a replacement. Found a surprising number of places selling those white plastic reservoirs. I know you need one 20 years older but might be possible - or maybe you could retrofit something close? I did a 5 minute search and found these guys.

https://www.opgi.com/cooling-heating/overflow-tanks-catch-cans/coolant-overflow-tank/tank-coolant-overflow-78-88-el-caminomalibumonte-carlo-l240901.html

Doesnt look like they have one for my car

 

[Odd-job]

+1 for the Polyvance stuff. Its like 3M in that its more expensive, but it just plain works which is why the professionals seem to pay up for it.

 

[larry4406]

I used a soldering iron to fix a rodent chewed hole in a lawn mower gas tank.

The tank had a reinforcement rib in a benign location that I trimmed to make "welding rods" from. I then used the soldering iron and donor plastic welding rods to melt and fuse the hole closed. Going on probably 3-4 years now minimum. I had posted this repair somewhere on GJ but damned if I can find it now.

 

[seber]

Plastic welding rigs that I have seen have all been for heavy wall. I suspect they would not do well on the very thin wall of a water reservoir. Have you tried warming it with a heat gun and then hot melt glue?

 

[AmericanMechanic]

https://www.amazon.com/dp/B00IEX6NME/?tag=atomicindus08-20

Polyvance Model 7.

Purchased one and fixed a crack over 6" long in a radiator.

What's more, I had a question, emailed the company, and the product manager for the kit replied back promptly, a couple of times. It's Made in USA and appears to all be US except for the Iron - I believe they said they haven't found a quality US made iron. But the rest including the control unit are US made.

Comes with a really detailed instruction book about how to identify various plastics, what each car body part, tank, etc most likely is, and how to weld.

Note: the company said there's a black unit (vs red linked above) that is a counterfeit. They actually suggested to purchase the one linked above.

 

[albundy]

Hey guys,

The coolant reservoir on my Wife's 84 Riviera has a small crack and has been dripping. New one simply not available. I could probably rough it up and try some type of "glue" but my experience has been that there really is nothing that sticks real good to the white plastic material these tanks are made out of. So I was thinking of trying one of the hot air type of plastic welders ?

Anyone have any experience with these ? Harbor Fright has one but it has quite a few lousy reviews as far as not lasting very long. Seems like when it works it works good.

Any thoughts on the entire subject would be appreciated. There have been a few times in the past that it would have come in handy on other projects too.

Thanks,

this dealer says they still have it, likely old stock collecting dust, but is the correct gm parts number. GM 22505434

Cadillac Seville Recovery tank. Reservoir. RADIATOR, Motors - 22505434 | Stingray Chevrolet, Plant City FL

Recovery tank. Reservoir. RADIATOR, Motors, General, FAN, Cooling. Cadillac Seville. Genuine Cadillac Part - 22505434. Ships from Stingray Chevrolet, Plant City FL

www.oemgmpartscenter.com

also the tank for the regal is still available, based on google images they appear built on the same platform and the tank is of similar design to the oem sketch. or you can find plentiful universal tanks in various configurations of plastic or aluminum on sites like summit, classic industries, etc.

as for plastic welding, i'm just getting my feet wet, but most youtube videos are hack at best. i'm sure the repairs hold, but ugly as sin. i spent some time researching "plastic welders" seems like there are high end hot nitrogen welders available. i would guess some plastics don't react well to oxygen or some other atmospheric gas like metal would.

the tank is likely polyethylene or propylene. most plastics need to be repaired with plastic. glues would not be favorable in this use case with hot coolant exposure. hot liquids in general have resulted in many failures for me regardless of adhesive type.

hopefully this helps.

 

[gregs]

I have two cheap plastic welding kits bought off ebay straight from the PRC, that I've only used once so far to fix a mangled ABS under engine splash tray or whatever it's called (a plastic excuse for a skid plate) for a late 90s Ranger that after what my boy says was a possum strike was dragging all the way home. Using both kits together they worked rather well for that repair. We got it back up in place and seemed to be very strong which is all I was hoping for.

One is the kind that heats up little staples that you melt/bury into the plastic and snip off after it cools (best used on the backside or side most out of view) and the other is an iron for melting additional plastic and screen/mesh if you want and spreading/smearing it around and smoothing it out. I think together I paid about $45-$50 in all. The only salvage yard around that said they had one wanted about that much for it and when we got all the way there it wasn't even close to the right one, so fixing the mangled one became plan B. In hindsight I'm glad because now I've got these for if/when I need them and a little experience with them goes a long way. I'm glad my trial run was for something out of sight.


most

I bought one of the hot melt staplers and use it fairly often to repair things. Its nice because its quick and adds some stability to the part. I bought it to repair the dash on my 2010 Suburban that all crack and fall apart. The backside looked like Frankenstein with all the staples, but its been holding up well.

 

[StillTooManyHobbies]

I used a soldering iron and milk jug for "solder" to fix a cracked riding mower gas tank and been working well for at least 5 years.

 

[MoonRise]

I have used a HF hot air plastic welder (with built in air motor) successfully to repair some automotive plastic parts. It's big, and a bit awkward to handle and loud enough to require hearing protection but it worked for me.

Plastic welding is a different 'feel' than metal welding. At first, I kept trying to get an actual molten puddle in the plastic and was just scorching the plastic. All you have to do is heat soften the plastic enough to get 'gummy' as you add the heat softened 'gummy' filler rod and press the parts together.

Practice, practice, practice before hand on some similar plastic type (different plastics 'feel' different when you soften them).

Identify the plastic type that you are dealing with and get matching (or compatible) filler rods. +99 on the Polyvance "Plastics Bible". Download it and read it.

CLEAN - CLEAN -CLEAN the plastic. Solvent clean, and scrape/abrasive clean it. Usually make a V on the crack/joint to add more surface area for the filler to fuse to instead of just glopping the filler on the surface of the parts.

Apply heat to soften the plastic part and then add the filler rod and push it into the soften plastic while still adding heat and let the filler also soften then and things all some together. Let cool.

Did I mention to practice first?

 

[humpty]

I have an air and airless rig for plastic welding. They both have their strengths and weaknesses, not to say you won't be able to but a thin and dirty coolant reservoir will take some experience to do with the air style. Personally I'd start with the airless. If it is cracked in a nice flat spot you might be able to bond a patch over it.

Plastic welding is a cool way to fix things but I still always try to replace if possible, way easier.

 

[Zeus36]

Love this guy's video's: