Alli crack/leak
Submitted by hekser on Sun, 2012-08-12 13:13
Hey all, just wondering if anyone can suggest something here- had a crack in the hull- got it patched up but after taking it out yesterday- seems its still leaking. is it possible to do a weld over a weld? ill take it to a shop to get it done doesnt matter the cost- cant put a price on my life.
can they cut out the shitty weld and put a patch over it? its an older hull- rego papers say trimcraft ; im guessing 80s.. so it will be pretty average..
failing that should i just sikaflex and hope for the best?
cheers,
Hekser
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thesupervisor
Posts: 1137
Date Joined: 10/06/09
biggest drama with ali is
biggest drama with ali is getting it clean enough to weld
it is possible to cut out and re weld new section in this takes time and money
depending n the value of boat and how long you think you will keep it before upgrading
sikaflex may be a viable option
it looks like that has been has that been hit from the other side then repaired
getting the bottom line final answer from a bunch of blokes that use false names and put smiley faces at the end of paragraphs is not the best place in the world to get the information you seek.
Wes F
Posts: 1060
Date Joined: 07/01/12
Old Ali
can be brittle and porous making it difficult to repair. Often when it's welded cracks appear around repaired area due to heat thats applied. Sikaflex is one option, I'm not sure what the product is called but it's like a knead it (two part mix) product like whats used for fixing radiators.
Old fishermen never die they just smell that way.
hekser
Posts: 572
Date Joined: 31/03/10
just bought the boat
had it in the water once (yesterday) and only caught snapper and cod. im thinking its good luck... i might stick with the sikaflex/ ali resin... probably not the best idea to weld again :P thanks guys
sea-kem
Posts: 14851
Date Joined: 30/11/09
Like older aircraft they can
Like older aircraft they can be retempered in an oven. But that's the expensive option. Maybe as above options. Hoiw did the floor beams hold up?
Love the West!
fishfish
Posts: 303
Date Joined: 01/09/09
patching ali
Lookin at that photo I would leave the repairs there, linish them flat and weld an ali patch say 3mm etc over the top of at least 50mm all the way around .
Putting a large piece over the area enables you to sand a better area back to clean ali and thats also probably thicker to enable a better weld rather than trying to weld up a crack or patching pin holes, corrosion etc which is a pain the arse !!!
Ive never had much luck welding up cracks in parts that are susceptible to alot of movement/flex,once they are cracked they tend to crack again due to metal fatigue and the heat required to repair them so you generally have to brace the area around it to help...
{note last sentence is in regard to where proper welding procedures cant be done ie pre heat/cool down etc }
cheers fishfish
hekser
Posts: 572
Date Joined: 31/03/10
the weld is inside the strake
so welding a patch over the top will still leave it exposed in the hollow of the strake - pack this with weld as well? (im not a welder...)
--- ---
\ /
--x--
x being the crack , i can put a sheet of alli over it and rivet it in and seal, but what about the opening on both ends?
hekser
Posts: 572
Date Joined: 31/03/10
yer they still holding :D cheers
im reading on google about a product called lab-metal : http://www.alvinproducts.com/products/products.asp?id=1 will try and get some of that in, or equivalent. would i be grinding away the existing weld first or just wirebrushing the whole area and packing it on top?
cheers
grantarctic1
Posts: 2546
Date Joined: 03/03/11
Stainless Steel Brush
Make sure you only use a Stainless Steel brush mate. Mild steel wire brushes will contaminate the Aluminium even more , causing more galvianic corrosion and a bigger problem later on .
Cheers Grant .
sea-kem
Posts: 14851
Date Joined: 30/11/09
Hey Grant I've just bought a
Hey Grant I've just bought a new acid passivator machine from Ensitech. Have you seen them. It will clean the welds stainless (gets rid of the burn stains) and ali and instantly repassivate. Have used it a few times and love it. No more corrosive gel etc. It wasn't cheap but for job finish it brilliant.
Love the West!
grantarctic1
Posts: 2546
Date Joined: 03/03/11
Yeah
Yeah have been looking at them but was waiting for some feedback on how they went. I didn't realize it worked on aluminium too. Sounds like a great machine if it gets rid of using those pickling gell's .
sea-kem
Posts: 14851
Date Joined: 30/11/09
Yeah it uses an organic acid
Yeah it uses an organic acid two differant types for ali and stainless. There's also a nuetraliser if you use too much acid. You're basically paying for the technology not the machine but definately worth it.
Love the West!
pale ale
Posts: 1755
Date Joined: 02/01/10
There is a product called
There is a product called Devcon - meant to be ok for your job.
fishfish
Posts: 303
Date Joined: 01/09/09
patching
Agree with Grant stainless wire brush only and now seeing where the crack is it makes it harder to patch but still do-able depending on your skills/who does it and access to equipment ie you can press a plate to follow the strake and weld it in otherwise as you said the ends are left open ...
This repair sort of depends on whos doing it and how much you can justify on spending otherwise maybe try a two part repair product once again its all in the prep !!!
cheers fishfish
hekser
Posts: 572
Date Joined: 31/03/10
thanks guys
a FW member is gonna have a bash at it later this week for me, we will see how it goes.. if looking bad, ill just go the 2 part product and make sure its prepped superbly- maybe grind a bit of weld back and rub it down to shiny metal.. be posting next week to let you all know the results- im hoping they are positive -
once again - thanks for everyones input.
cheers,
hekser
Splashback
Posts: 82
Date Joined: 25/06/12
devcon is the shit
I would like to throw my two cents worth in about devcon. stainless wire brush as mentioned before then mix this stuf, two parts, and pack it on. use a very wet hand to smooth it over. It gets hot as the catalyst works and is very workable. If you are very SOR I have a tin you can come and have a dip from. I have eliminated all the old leaks and dribbles from my tinny with this stuff. It is sandable and paintable and I have even seen it drilled and tapped before successfully on a pump housing.
Josh
Rods: a few
Reels: a few too
Personal best: eaten and forgotten
Location: North Mandurah
hekser
Posts: 572
Date Joined: 31/03/10
nice!
i am sor, not as sor as you :D but if i cant get it sorted with a weld then i might have to take you up on that offer
rather someone who has experience with it show me what im doing thatn just have a go and fk it up myself. cheers mate
tim-o
Posts: 4657
Date Joined: 24/05/11
Haha gotas love the sika and
Haha gotas love the sika and devcon recommendations, always a bodgy way to do someting. If a welder fabricator cant fix it then theyre in the wrong trade
I am, as I've said, merely competent. But in an age of incompetence, that makes me extraordinary.
carnarvonite
Posts: 8627
Date Joined: 24/07/07
Devcon + Sikaflex
If you are going to weld it again do not put devcon or sikaflex / silicon on it because it gets in to the metal and makes it bbble when they try to tig or mig weld it. They will have cut the piece out by the look of it go get back to clean metal.
Walfootrot
Posts: 1386
Date Joined: 23/07/12
God why! spend the time an
God why! spend the time an money and do it right, drill the ends of the cracks, then weld from the drill hole to the center of the crack, back grind to clean metal, then fill.
Or bog it up and learn how to swim with sharks.
What is with bogging hulls up????/ Realy
More drum lines, kill the bloody sharks!
sea-kem
Posts: 14851
Date Joined: 30/11/09
I'm going to have at go at
I'm going to have at go at this again guys. I did the first weld repair and it was a good fused weld and I said to Hekser there's no guarantees due to old brittle ali factor. I will use my new you bewt metal cleaning machine to hopefully clean out a lot of the impurities and put a patch wide of the original repair. But as I mentioned before it would make a hell of a differance if the ali was retempered eliminating stress on the parent metal.
Love the West!
thesupervisor
Posts: 1137
Date Joined: 10/06/09
any chance you take some pics
any chance you take some pics during the job inclinding the before and after the metal cleaning machine
people bagging the sika/devcon yes its a comprimise but if you cant get a fabricator for the right price its a option
if i had to price that it would be around the $400 to do it properly with a warrenty is it worth it on a boat thats worth a few grand
getting the bottom line final answer from a bunch of blokes that use false names and put smiley faces at the end of paragraphs is not the best place in the world to get the information you seek.
sea-kem
Posts: 14851
Date Joined: 30/11/09
This is an example of a
This is an example of a stainless job I did recently.
Love the West!