Will epoxy stick to stainless steel?

[SpaceCygnet]

Has anyone experience of using epoxy on stainless steel? I have a leak somewhere on fuel tank - I cannot see any pin holes or tell where exactly leak is coming from. I was thinking to applying a coat of over the welded edge where Isuspect leak is coming from - would that work?

 

[TradewindSailor]

Epoxy will stick to stainless steel ...... BUT it has to be very clean and recently abraded.

1 Abrade the stainless steel with 80 grit

2 Apply the epoxy resin. Scrub it into the surface with 80 grit paper while it is still fresh.

3 Before the epoxy has started to cure ..... epoxy glass over the top.

HOWEVER ..... The bond is unlikely to be full strength, so I wouldn't rely on it, but it may hold for a while.

I'd still get it welded or replace at the next oportunity.

 

[lw395]

Epoxy can stick pretty well to stainless if you can degrease it totally and roughen the surface.
Wet and dry, coarsest you've got, used with water and fairy liquid will degrease, but if you have a pinhole that's oozing petrol or diesel, that will very probably cause a 'fisheye' hole in the epoxy.
So it may be necessary to clean inside as well.
It might be worth putting a layer of glass tape with epoxy along the seam? It will make the repair less fragile.
welding or brazing, maybe even soldering might be better in the long run.
Good luck.

 

[lw395]

Epoxy will stick to stainless steel ...... BUT it has to be very clean and recently abraded.

1 Abrade the stainless steel with 80 grit

2 Apply the epoxy resin. Scrub it into the surface with 80 grit paper while it is still fresh.

....

HOWEVER ..... The bond is unlikely to be full strength, so I wouldn't rely on it, but it may hold for a while.

QUOTE]

Agree it will not be that strong, OK for keeping the fuel in, not ok for holding the tank together!
Scrubbing in the epoxy is a good move.

I would still do a degreasing step first, either detergent or solvent, and let dry first.
If you are sure fumes are not an issue, warming the epoxy on the job to about 60degC using a hot air gun often helps. Not if it still smells of fuel though!
If the tank has been well washed out, I might heat the repair area after degrease to ensure no water or solvent is trapped in the pinholes.

If you put glass tape in the repair, if it fails it should be obvious, the tape will peel away.

 

[Anthony]

I had a leak from stainless fuel tank that I couldnt trace, removed tank, sealed outlets and put a little bity of pressure in it, as side flexed it revealed a crack in one of the worlds, basically it opened and closed as teh side panel flexed slightly.

I can not imagine epoxy would have sealed that for long, once found and welded its had of course been fine.

Personally I would try to trace the exact leak, and consider it maybe a hairline crack that it hardly visable in some circumstances.

Ants

 

[Ubergeekian]

I can not imagine epoxy would have sealed that for long, once found and welded its had of course been fine.s

I have mended two mild steel petrol tanks with specialist two part fuel tank repair putty. One lasted 20 years before the tank was lost: the other is still going strong. As far as I know it works for diesel too and I see no reason why it should not work on stainless.

 

[oldsaltoz]

It is essential that the area is properly cleaned before any sanding or other cleaning.

Any contamination will just be spread over a larger area when you start sanding.

Acetone will remove most contaminants including diesel, use only white cotton rags.

Hope this helps.

 

[CET1]

Another vote for Granville Petro Patch Putty Multi-purpose Metal Repair - 50g

Just Mix It And You've Fixed It

Cures in just 1 hour
Use on steel, lead, cast iron, alloy, brass, copper and glas fibre

Granville Petro Patch Putty is a fast acting Epoxy Putty with hundreds of uses around the car, home and industry.

we use it at work great for quick temp repair.

 

[SpaceCygnet]

Thanks for replies. I have not come across Granville Petro Patch Putty, so I might look out for that. Is it widely available? The tank was emptied in November, so risk of fumes etc should be low. The repar will not be for strength, just to try and stop leak. Leak is small, only noticed towards end of last season. As usual, accessing or removing tank not easy but long term, I may need to do that. But as leak is small, its worth trying a few repsirs before I'm forced to remove it!

 

[Bosun Higgs]

Putting a patch on the outside is the wrong way to do it since the pressure of the fuel in the tank will be trying to peel off the patch and eventually succeeding.

Classic car and bike owners have this problem fairly often and use a special tank lining fluid which effectively coats the inside of the tank with a membrane. Try asking what they use on one of their forums.

 

[lw395]

Putting a patch on the outside is the wrong way to do it since the pressure of the fuel in the tank will be trying to peel off the patch and eventually succeeding.

Classic car and bike owners have this problem fairly often and use a special tank lining fluid which effectively coats the inside of the tank with a membrane. Try asking what they use on one of their forums.

The pressure should not be that great. (although you have to allow for the tank brimming to the top of the filler or breather). If the holes are small the force is small compared to the peel strength around the edge of the hole. A real engineer would do some sums at this point

I think the liquid you mention is 'petseal'. Pet as in petrol not cat or dog!
I don't know if it's good for diesel too.
I've heard it works ok on the bottom of a tank, you may have difficulty on a top seam.
There is not much surface area in the bottom of a bike tank where the rust happens, and the rust gives a good key.
I've used araldite successfully on motorbike tanks, both steel and alloy FWIW.
There is some merit in having the repair/patch outside where you can inspect it IMHO.

There's more than one way of skinning a cat as they say, (but you only get one go per cat)

 

[Ubergeekian]

Putting a patch on the outside is the wrong way to do it since the pressure of the fuel in the tank will be trying to peel off the patch and eventually succeeding.

Classic car and bike owners have this problem fairly often and use a special tank lining fluid which effectively coats the inside of the tank with a membrane. Try asking what they use on one of their forums.

I'm a classic car owner. We use petro patch. I have had no problems with long term use.

You may be thinking of "Slosh and Seal" which I think comes from Woolies and is for dealing with tanks which have lots of surface rust inside rather than small holes.