Join Date: Sep 2004
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Buy a Dremel tool and lots of metal grinding stones, diamond tipped tools, sanders, etc.
Attack the blisters with the Dremel and go to bare metal. Make it as clean as you can. You'll need to find the edges of the blister where there is good paint-metal adhesion. There will be some pitting and you won't get all the rust, but get as much as you can.
Then treat the area with Ospho or other phosphoric acid rust converter (Turns the FE Oxide to FE Phosphate or something like that). Clean that off and then paint it. Choice of systems is up to you. One is mentioned above, the system I've used for 10 years involves successive coats of Interlux and Alwgrip as follows:
On the cleaned/chemically treated metal start with
Interlux Vinylux etching primer -- one thin coat followed within 24 hrs by
Interlux Interprotect 2000 -- two coats of this 2 part epoxy, then
Fill and fair with a 2 part filler -- Interlux makes fillers for above and below the waterline, followed by:
Your choice of finish paints -- in my case -- sprayed on Alwgrip epoxy primer and then Alwcraft 2000 (which is much easier to "patch" than Alwgrip.)
I usually leave the final two stages (Alwgrip) to professionals, but I'm working up my courage to try the finish painting myself.
I've done patches/repairs this way for over 10 years. Some of my early ones are still perfect. Some I did two years ago are back for another round of repair. I think it all depends on the quality of the prep and whether you got all the rust / oxide treated before it was recoated.
Nothing beats steel for strength, but you do need to be diligent about the rust. Take as much care with the inside as you do the hulll, but inside you can skip the shiny paint finish steps.
PS -- I forgot to mention -- also buy a very good shop vac with lots of suction. Keep the suction going at the point where you're grinding off the rust. Whatever grinding dust escapes the vac hose will find it's way into your non-skid and you'll have lots of tiny rust spots all over your deck.
Last edited by billyruffn; 07-16-2011 at 06:00 PM.