Rust repairs

[Bugatti]

Well done Pdiddy

Looking good. Great to see you're getting into it


Cheers, Bugatti , , , , you can come and do my Boat after

, , , , pleeeeeeease

[SteveoTheTiger]

Its worth mentioning that the Surtees Workmates have an under deck kill tank that you fill by removing a bung until you are happy with the water level then you put the bung back in.

[Pdiddy24]

Thanks Bugatti! Inspired now. If you want your boat to be a floating then sinking death trap, I'd be more than happy to help out!

I haven't got a Surtees Steveo..

[re-tyred]

Some stories there!

Ok - so after some inspiration and pep talk and dr google I've had a crack at removing the rivets and bung inserts. See photos below
There is no obvious rust through the hull if that makes sense and appears to be just on the surface areas around where the rivets were.
For the rust is it a case of grinding this back and then use the above mentioned techniques to treat it?

Also for one of the bungs there are only 3 holes drilled all the way through as the transom middle support brace obstructs this. I won't be able to get a bolt and nut through that hole - is there an easy solution for that section?

Excellent job and I bet you feel a little pride for having a go. It is very satisfying doing it yourself.
When putting new or even the old inserts back in. The one that goes into the rib and has no inside access, I would pop rivet it with the blanked off aluminium pop rivet shown earlier in the thread. Alternatively you could use a stainless steel self taping screw. This is a poor alternative as it will eventually come loose. It will not compromise hull integrity as worst case is it would fill the rib with water. ( I bet the previous one leaked into there as well) If you pop rivet you need a small stainless washer between the pop-rivet head and the plastic. I.E you place the washer on the rivet then insert it and then pop rivet. If you don't have pop-rivet kit I would go and purchase one. As the owner of an ally boat you will have the use for it. Make sure you get good quality marine rivets that are blanked off as shown in other post. So procedure would be something like this.
Get bolts washers and nuts (Nylox nuts) , pop rivet and gun. goop for the threads, sikaflexx to go under the plastic inserts.
Sika around the holes. Insert plastic inserts. Goop the threads and do up bolts. Goop the rivet and put it in. Clean up the excess sika with paper towel and turps. Spend a bit of time on that as it is easier than trying to do it after it sets. Clean up your hands as it is darn hard to get taht sika off your hands after it dries.
Last tip when buying Sika. Get the smaller tubes, as after opening, it doesn't last. I know they are 3 times the price for the amount but if you buy the big tubes to use with a gun you will find it is set solid when you go to use it next month.
If you use a silastic product, instead of Sika, on your boat, make sure you use a non acid cure product.

[Bugatti]

Exactly as re-tyred has said , , , , exactly

Only addition I would say is to "de-burr" any holes you drill (or any existing holes). Especially with Aluminium as it is a softer metal and burrs up a lot. By de-burring the hole (on both sides), you get a snugger fit with what ever you're fixing to it. Also a a bit of sanding to get the whole contact surface where the fixing (Bung Flange in this case) is nice and flat for better contact.

They do make/have de-burring bits which can be pricey. I just use a larger drill bit and hand turn it around the hole and that cuts the burr off the rim of the hole.

Sounds like a great little job for you

Cheers, Bugs

[Pdiddy24]

You're spot on Re-tyred! Only took 15 min to get them out. Pretty stoked. Will start grinding the rust spots back this weekend. Reckon I got this haha Thanks so much for the useful explanation. Really well explained. I'll get all of the above to get the ball rolling on this. The old bung inserts are in pretty good nick so will probably use those. Any thoughts on having one of the bungs face internal of the boat? I'll struggle to get one of them to face internal due to the rib location obstructing it.

And as you said a rivet has been put through the rib. I can't see any obvious signs of rust but can't be 100% sure. If there is salt water sitting at the bottom of that rib would that be a killer? Probably more concerned if there is any rust issues internal of that rib though.. I'd need to drill through to fully investigate this though.

And thanks Bugs! I'll add that to the check list as well. I'll see how I go with the drill and grinder to smooth that out. Legend!

[Brett]

I wouldn't use a grinder, just use some wet and dry sandpaper or a new fabric scourer(the green ones you use on dishes in the kitchen).
The rust you see left on the alloy, should only be surface stain, not actual rust.

[Pdiddy24]

OK awesome. Thanks Brett. I'll start off with that