Hi guys seeking advice from the brains trust once again.
Finally got this bastard out today after breaking a timber that the the builders decided to screw in and then glass over all the heads. Anyone know a reliable stainless steel fabricator in Sydney capable of duplicating this or better still anyone who could make it out of rigid plastic?

I use knead it from Bunings

I would just fix that one. If it's a porous weld you could grind it out and reweld with arc but the easy way is JB Weld. Abraid the area and clean with acetone. Smear JB Weld over the leak area and apply a little heat with a hot air gun. Leave for a day or so and then test. Use plenty of JB Weld and when reinstalled ensure the glue is not going to rub anywhere.

www.hellfabengineering.com.au/about-us

Thanks once again guys. Like the sound (cost) of repairing it. There was a lot of rusty gunk that came out once I drained it so the rust inside might be extensive. I will try and clean it out a bit today and have borrowed one of those cameras on a wand which will hopefully allow me to have a look at the inside condition particularly the welds. Don't want to repair one pinhole only to find others appearing with increased frequency in the future as getting it out is a mission.

I would find a ss fabricator that is happy to do small jobs. I recently had a ss liferaft holder altered that would of taken a couple of hours to carry out, cost $330. Repairing a couple of welds would be similar.

Might be better to get a new plastic one from a RWB agent;

rwbmarine.com.au/flexible-drinking-water-tanks-heavy-duty.html

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r13 said..
Might be better to get a new plastic one from a RWB agent;

rwbmarine.com.au/flexible-drinking-water-tanks-heavy-duty.html

Yes thanks I looked at flexible ones but the fillers are all on the top rather than in the end due to the fact that there is a seam in the end and I don't have the height. Not sure Id fully trust a flexible one long term either although they would be pretty easy to replace once they gave up plus the price is right.

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Ilenart said..
I would find a ss fabricator that is happy to do small jobs. I recently had a ss liferaft holder altered that would of taken a couple of hours to carry out, cost $330. Repairing a couple of welds would be similar.

Yes thanks for that. I was on the way down to get some 0.55mm thin stainless steel that I could bend into right angle strips around the welded seams with JB weld in between the tank and the steel when I remembered I had the phone number of the guy who made my solar bimini hoop and he was interested and price sounded pretty reasonable so I might show the tank to him and see if he can repair it. Nice little fine geysers when I tested today to see where leaks were.

Your obviously handy, so how about epoxy glass a ply tank up or just epoxy glass tape up the suspect seams of tank you have. Many old triumph ( and others ) motor bike fuel tanks have been resealed by pouring neat epoxy in and rolling the tank around to create a lining.

My boat has had epoxy ply water and holding tanks for 21 years. Make the tank like the one you have yourself out of 9mm ply and coat generously with 4 coats of rolled epoxy.
Put an inspection hatch on it and you can always fix it with a bit of glass and epoxy. Not that I have needed to.

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woko said..
Your obviously handy, so how about epoxy glass a ply tank up or just epoxy glass tape up the suspect seams of tank you have. Many old triumph ( and others ) motor bike fuel tanks have been resealed by pouring neat epoxy in and rolling the tank around to create a lining.

Rolling sealant around the inside sounds interesting and in fact there is a specific product for this purpose see here.www.ebay.com.au/itm/Motorcycle-Fuel-Tank-Sealer-Repair-Kit-KBS-Stop-Rust-and-Corrosion-Motorbike-/273480652172?mkcid=16&mkevt=1&_trksid=p2349624.m46890.l6249&mkrid=705-154756-20017-0

This is the small kit but for $130 there is another kit for 100 litre tanks. Bit of mucking around with nasty chemicals but I like the idea of fixing the rust on the inside before it reoccurs rather than patching the outside. I could of course do both. I guess I will decide tomorrow after speaking to my metal fabricator who tells me he can do the job for $200 Max. Hard to go past that price especially considering it requires little or no effort on my part. Thank you everyone else for your great ideas.

Can you get a bladder inside the existing tank? otherwise just put a bladder in the space they are fine

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troubadour said..
Can you get a bladder inside the existing tank? otherwise just put a bladder in the space they are fine

No unfortunately a bladder won't fit as there is only 360 maximum height tapering to nothing on the outboard side and bladders require 50mm or more for the inlet elbow to stand up on the top not to mention that they have inlet in the wrong place for my boat

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julesmoto said..

woko said..
Your obviously handy, so how about epoxy glass a ply tank up or just epoxy glass tape up the suspect seams of tank you have. Many old triumph ( and others ) motor bike fuel tanks have been resealed by pouring neat epoxy in and rolling the tank around to create a lining.

Rolling sealant around the inside sounds interesting and in fact there is a specific product for this purpose see here.www.ebay.com.au/itm/Motorcycle-Fuel-Tank-Sealer-Repair-Kit-KBS-Stop-Rust-and-Corrosion-Motorbike-/273480652172?mkcid=16&mkevt=1&_trksid=p2349624.m46890.l6249&mkrid=705-154756-20017-0

This is the small kit but for $130 there is another kit for 100 litre tanks. Bit of mucking around with nasty chemicals but I like the idea of fixing the rust on the inside before it reoccurs rather than patching the outside. I could of course do both. I guess I will decide tomorrow after speaking to my metal fabricator who tells me he can do the job for $200 Max. Hard to go past that price especially considering it requires little or no effort on my part. Thank you everyone else for your great ideas.

I think you will find that the expensive tank repair kit is good ol epoxy, price varies but bottom line more you buy the cheaper it gets, & the more you find out what it can be used for the more you use, imho 5kg ish isn't to much, I pay the few extra sheckles and get a 2;1 mainly because even a dill like me can count to two

What about Atlas tanks, they make custom in roto mould plastic.

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Stockie said..
What about Atlas tanks, they make custom in roto mould plastic.

Thanks for that. Got a quote of them today $875 plus delivery from Brisbane to Sydney so might just go with the epoxy solution inside and out. Not that that is unreasonable for a custom-made molded product. Actually it's about the same as I was quoted for a new stainless steel tank. Price would probably come down a lot if I found a few other people from the North Shore group.

Hi Jule
"might just go with the epoxy solution inside and out"
This would indicate that you have access to the internals of the tank


How about this for a plan?

Cut the ends off with a mini grinder and cutting disc,
Clean up and inspect both surfaces (the ends and the tank itself. ( 2-3 hours)
If condition is satisfactory, continue.

Get someone to bend up 4 cm by 4 cm 1.5 mm stainless angle .
I mean a long 8cm wide strip bent as angle iron but made of thin (manageable) material.
Cut the angle to length and pop rivet to the ends. (1 hour)

Place the ends on the tank and pop rivet (1 hour)
Seal inside and outside with a top quality mastic or sikaflex water proof sealer. ( 2hours)
The internal static water pressure would push the sealant into the gap between the tank ends and angle.
An alternative to chemical sealant would be good old-fashioned solder. It was good enough for rainwater tanks.

Cheap and doable with simple tools.

I hope my explanation is understandable.

gary

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garymalmgren said..
Hi Jule
"might just go with the epoxy solution inside and out"
This would indicate that you have access to the internals of the tank


How about this for a plan?

Cut the ends off with a mini grinder and cutting disc,
Clean up and inspect both surfaces (the ends and the tank itself. ( 2-3 hours)
If condition is satisfactory, continue.

Get someone to bend up 4 cm by 4 cm 1.5 mm stainless angle .
I mean a long 8cm wide strip bent as angle iron but made of thin (manageable) material.
Cut the angle to length and pop rivet to the ends. (1 hour)

Place the ends on the tank and pop rivet (1 hour)
Seal inside and outside with a top quality mastic or sikaflex water proof sealer. ( 2hours)
The internal static water pressure would push the sealant into the gap between the tank ends and angle.
An alternative to chemical sealant would be good old-fashioned solder. It was good enough for rainwater tanks.

Cheap and doable with simple tools.

I hope my explanation is understandable.

gary

Thanks for that but no the internal seal will be via a kit that pours in via the inlet or outlet and coats the inside of the tank and particularly the seams with epoxy. It does not require opening of the tank in any way. Just to make sure I will also add fibreglass tape and epoxy to the outside. I would prefer to avoid opening the tank although obviously that does have some advantages to see the full extent of any damage.

I am big fan of epoxy and use it lots. I have done a little bonding to metal. Last job was a radiused 10cm diameter alloy tube that I kerfed and then used epoxy and double bias to strengthen. It worked nicely.

But I would not like your chances of getting glass and epoxy to be waterproof on the outside of a stainless water tank, especially when you can't wrap around it.

To get a really nice bond to to metal (well you don't really) but to get the best bond the usual technique is to apply clear epoxy and then sand the metal with about 120 grit paper. This is really stressed with passivating metals, like aluminium and stainless.

Even if you could get the epoxy to stick to the outside of the tank, you will not get any glass to do a right angle on the outside of the tank. I have spent many, many hours doing this sort of thing and I have lots of tricks but I need a radius of about 4mm minimum with a really nicely rounded and faired edge and some tricks with light fabric. You won't get that on the outer edges of the stainless tank and it will almost certainly leak.

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julesmoto said..

Stockie said..
What about Atlas tanks, they make custom in roto mould plastic.

Thanks for that. Got a quote of them today $875 plus delivery from Brisbane to Sydney so might just go with the epoxy solution inside and out. Not that that is unreasonable for a custom-made molded product. Actually it's about the same as I was quoted for a new stainless steel tank. Price would probably come down a lot if I found a few other people from the North Shore group.

You will be chasing leaks forever, shell out and get a new custom plastic one

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Kankama said..
I am big fan of epoxy and use it lots. I have done a little bonding to metal. Last job was a radiused 10cm diameter alloy tube that I kerfed and then used epoxy and double bias to strengthen. It worked nicely.

But I would not like your chances of getting glass and epoxy to be waterproof on the outside of a stainless water tank, especially when you can't wrap around it.

To get a really nice bond to to metal (well you don't really) but to get the best bond the usual technique is to apply clear epoxy and then sand the metal with about 120 grit paper. This is really stressed with passivating metals, like aluminium and stainless.

Even if you could get the epoxy to stick to the outside of the tank, you will not get any glass to do a right angle on the outside of the tank. I have spent many, many hours doing this sort of thing and I have lots of tricks but I need a radius of about 4mm minimum with a really nicely rounded and faired edge and some tricks with light fabric. You won't get that on the outer edges of the stainless tank and it will almost certainly leak.

Thank you for that heads up. Might have to rethink glassing the outside.

JB Weld sticks fine to stainless. I use it on my race car on alloy welds to cure leaking problems with crook welds [porous]. Another option is to lay another weld with arc along the pin holes. Or you could wash some silver solder or braze along the edge with the pin holes. That side area would need oxy acetalene to get the SS to get hot enough. Gas blowtorch would do the job but would take a lot longer.

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Ramona said..
JB Weld sticks fine to stainless. I use it on my race car on alloy welds to cure leaking problems with crook welds [porous]. Another option is to lay another weld with arc along the pin holes. Or you could wash some silver solder or braze along the edge with the pin holes. That side area would need oxy acetalene to get the SS to get hot enough. Gas blowtorch would do the job but would take a lot longer.

Thanks for that. I was just a bit worried about chipping it off as I juggle the tank into position and as the tank bears on the hull. It's decision time tomorrow as I'm showing the tank to my welding guy in the morning. I've already resolved to use the internal kit that I have already bought so the issue is only what I do with the outside now

Running a tig torch over the leaking welds and adding s/steel filler where necessary
is the best way to do the repair.

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Jolene said..
Running a tig torch over the leaking welds and adding s/steel filler where necessary
is the best way to do the repair.

As long as the welder adds enough filler. Tig welders tend to make pretty welds.

Thank you all for your very valuable advice. In the end my welder pressure tested the tanks said I had hundreds of tiny little holes not on the weld lines but just back from the weld lines as depicted in this picture.
I had already ordered the kit depicted in the 2nd picture attached which comprises some Cleanser, some rust converting/etching product and then an epoxy paint/sealer.
It is intended to be applied inside the tank. I also ordered JB weld in a professional size for the outside but in the end I don't think I need it.
The product seems to be fantastic in so far as after inserting the paint and turning the tank every which way and draining much of it back into its can I put a rusty old baking tray under the outlet just to catch the last few drips.
There proved to be a bit more than a few drips and although I can't play with the inside of my tanks if the epoxy paint sticks inside the tanks anything like it has stuck to the baking tray I am ecstatic.

Effectively I think I have a plastic tank with the old steel tank just acting as a female mould. I guess time will tell but the product gets my vote.