Aluminum & and J-B weld for fixing rust ?

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caprikid61
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Aluminum & and J-B weld for fixing rust ?

Post by caprikid61 » Thu May 02, 2019 8:08 pm

Hi folks , I am trying to think of ways I can get the rust to stay away longer on my capri . I always just use p38 filler after removing all the rust but it just comes back the next year . What about using J B weld to bond and aluminum onto a lip / edge that is thinner than the panel then using filler to finish it off ? Would that keep the rust away longer ?? . Thoughts please

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Re: Aluminum & and J-B weld for fixing rust ?

Post by Not_Anumber » Thu May 02, 2019 8:57 pm

Grind it out and mig weld a small plate in there and then apply several thin coats of a decent primer . You can hire a mig welder or even better buy one 2nd hand for not a vast amount and then you will be setup for being able to do proper body repairs for years to come.

Filler is fine as a thin skim to blend in a joint over a welded repair or for shallow ripples in the bodywork. Decades ago I used to mess about with filling holes using p40 and/or fibreglass matting with a skim of p38 filler over the top. Sometimes it lasted, usually it didnt last very long. I stopped doing it.

You cant beat a metal repair and not only will it give you a known result each time it's an awful lot more satisfying knowing that the effort you are putting in is actually going to last and you wont be worrying about the filler cracking and spoiling an otherwise nice paint finish.

Aluminum and JB weld- its certainly better than just filler just be certain to clamp the plate in place well whilst the JB weld is hardening so that it cant loosen later due to vibration when the car is in use.

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Re: Aluminum & and J-B weld for fixing rust ?

Post by Peter-S » Thu May 02, 2019 9:31 pm

Cutting out is always going to be the best bet but if grinding back treat the metal with a rust converter (Jenolite or something similar) even if the metal looks clean. Also bear in mind that most rust comes from behind a panel where there is little paint protection so make sure you seal and protect the back of your repair.
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Re: Aluminum & and J-B weld for fixing rust ?

Post by Taff50ish » Fri May 03, 2019 6:30 pm

Hi there,

I had the same issue recently, I did not want a full back to metal re-spray etc, but for a year I would knock out a bit of rust and fill and cover over, a few months down the line and the rust is showing again. I had already decided I was going to have the rust cut out, welded in new metal and paint the local area. But it took a year to have the balls to have a cutter / grinder taken to my baby, but I’m so glad I did.... the repair now is solid and will not rust again, nor will it spread and just keep getting worse, it has been stopped in it’s tracks!!! Definitely the only way before you lose the war!!! Best of luck,

John...

P.S. I had this done at a garage for me, for a lot less than you might expect!!! And the guy knows Capris.... bonus.....

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Re: Aluminum & and J-B weld for fixing rust ?

Post by caprikid61 » Sat May 04, 2019 11:00 pm

Not_Anumber wrote:
Thu May 02, 2019 8:57 pm
Grind it out and mig weld a small plate in there and then apply several thin coats of a decent primer . You can hire a mig welder or even better buy one 2nd hand for not a vast amount and then you will be setup for being able to do proper body repairs for years to come.

Filler is fine as a thin skim to blend in a joint over a welded repair or for shallow ripples in the bodywork. Decades ago I used to mess about with filling holes using p40 and/or fibreglass matting with a skim of p38 filler over the top. Sometimes it lasted, usually it didnt last very long. I stopped doing it.

You cant beat a metal repair and not only will it give you a known result each time it's an awful lot more satisfying knowing that the effort you are putting in is actually going to last and you wont be worrying about the filler cracking and spoiling an otherwise nice paint finish.

Aluminum and JB weld- its certainly better than just filler just be certain to clamp the plate in place well whilst the JB weld is hardening so that it cant loosen later due to vibration when the car is in use.
I aggree that welding would be the best option but I dont have a power supply at the lock up where I will be doing the work. Never used a welder so I guess the J B weld is my best bet , I will give it a try in a few weeks if the weather improves as I need a bit heat to help dry the paint. Thanks for the info .

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Re: Aluminum & and J-B weld for fixing rust ?

Post by caprikid61 » Sat May 04, 2019 11:06 pm

Peter-S wrote:
Thu May 02, 2019 9:31 pm
Cutting out is always going to be the best bet but if grinding back treat the metal with a rust converter (Jenolite or something similar) even if the metal looks clean. Also bear in mind that most rust comes from behind a panel where there is little paint protection so make sure you seal and protect the back of your repair.
Thanks Peter , I will make sure the back of the panel is well protected , there is not a lot of rust showing at the moment but as soon as I start removing the old filler there will be plenty of holes for me to fill :banghead: will keep you posted.

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Re: Aluminum & and J-B weld for fixing rust ?

Post by caprikid61 » Sat May 04, 2019 11:16 pm

Taff50ish wrote:
Fri May 03, 2019 6:30 pm
Hi there,

I had the same issue recently, I did not want a full back to metal re-spray etc, but for a year I would knock out a bit of rust and fill and cover over, a few months down the line and the rust is showing again. I had already decided I was going to have the rust cut out, welded in new metal and paint the local area. But it took a year to have the balls to have a cutter / grinder taken to my baby, but I’m so glad I did.... the repair now is solid and will not rust again, nor will it spread and just keep getting worse, it has been stopped in it’s tracks!!! Definitely the only way before you lose the war!!! Best of luck,

John...

P.S. I had this done at a garage for me, for a lot less than you might expect!!! And the guy knows Capris.... bonus.....
Hi John , sounds like your garage did a good job for and as you its a more permenent fix . I will give the J B weld a try this year and if I still get rust coming through I will just have to bite the bullet and get a garage to do the job for me . I will keep you posted on how it goes but I think the hardest part is going to be how to clamp a patch of alloy on to the side of wing ?? Might not be easy . Cheers Alex

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Re: Aluminum & and J-B weld for fixing rust ?

Post by pbar » Wed May 08, 2019 6:10 am

caprikid61 wrote:
Sat May 04, 2019 11:00 pm


I aggree that welding would be the best option but I dont have a power supply at the lock up where I will be doing the work. Never used a welder
You may wish to consider a generator. Make sure you get one which can cope with a welder though as it takes a lot of juice, a standard 3KW one will struggle with a welder on anything but the lowest setting. And welding isn't so bad to learn. The initial cost of a generator and welder would soon be paid back with being able to do your own repairs. It's worth thinking about.

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Re: Aluminum & and J-B weld for fixing rust ?

Post by Not_Anumber » Thu May 09, 2019 3:27 pm

and indeed you can recoup the cost even quicker if you help a few people out by welding the odd patch on a sill following an MOT failure.

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