Boom looking a bit sad and sorry, any ideas? [updated]

[Troppo]

Finally got around to taking the boom off for a bit of refurbishing. Was in worse condition than I thought.

Here's some pics and possible repairs I might do. Please let me know your suggestions.

Once the gooseneck s/s bit was removed, underneath is quite corroded and something or other has made a ragged hole on both sides. Not sure what to do with this. I could use new bolts and coat all dissimilar metals with Duralac or Tef-gel. Not sure if the pitting has made it too weak.

boom 02.jpg (387.74 KiB) Viewed 5565 times

The topping lift connector has been gone a long time. How do these plug-ends come off? MIght be able to get a loop welded on.

boom04.jpg (281.65 KiB) Viewed 5565 times

One bolt was holding the clew track on. Two of the holes still have bits of bolt in them. Heap of corrosion under the right hand end where the bolt is not move-able. Any ideas for getting the old bolt off? I guess to put new bolts on I need to take out the end plug to have access inside the tube.

boom05.jpg (378.21 KiB) Viewed 5565 times

Other boom bits are held on by rivets, though in this case with six holes there are only two rivets. Another bit like this is held on by a bolt completely through the boom, possibly once had rivets but corroded through so a bigger bolt was bunged all the way through. Maybe I can move the fittings, put Duralac or Tef-gel underneath to stop the dissimilar metal corrosion then re-pop rivet.

boom06.jpg (345.02 KiB) Viewed 5565 times

So, what do you reckon?

troppo

[Phillip]

Louis,

First, to get that end fitting off you will have drill out the 3 pop rivits.
Duralux would have been used when it was put together so you will have to be violent to get it off.
Use a small cold chisel and work your way around the edges until you get some movement.
Last time I did this I then held the end fitting in a vice and worked the boom around until it came lose.
I repaired all the holes in the fitting with one of those plastic steel fullers.

At the gooseneck end you may have to consider cutting off the corroded part to start again.
There should be just enough length in the boom to allow this, but check first with your mainsail.

With the clew tack just move it back a bit and start again [drill and tap the holes, use a locking nut inside].
Remove that bolt by grinding the head off. Full the holes with plastic fuller.

The main sheet and vang hangers should have at least two SS bolt [with locking nuts] going all the way through the boom.
The other holes can be pop rivited but only use Mono pop rivits and plenty of Duralux.

Good Luck.

[bornfreee]

Troppo my boom broke in half i thought that was the end of it but a very smart engineer made a plug and sleeved it, it was a very good fix

[bearmcnally]

Yeah ! don't be a tight arse and buy a new section ?

Kindest regards Bear

[Troppo]

Update: I got the work done on the boom some time back so decided I shouldn't be slack with posting up the progress. One of the main things I did was to try and insulate the stainless steel from the aluminium as the two metals touching causes galvanic corrosion. Used some plastic tape and an expensive paste called Tefgel.

Boom end: Could not get the end fitting out. Could have simply screwed a new hanger for the topping lift onto the boom end the way it was but since the bolt holding the clew track would not come off, I decided on surgery. While some of the end cap got amputated, there was enough left to use. Plenty of boom length so the track fitted no problems. Took a bit to get the piece of boom off the end cap as it was so corroded together. With the end cap off, I could get the clew track off, restored, and back on properly. Under the stainless steel track, I insulated it from the aluminium using tape. All stainless steel bolts were coated in Tefgel to hinder the dissimilar-metal corrosion.

I always like to hack into things to repair them!

boom 6.jpg (444.6 KiB) Viewed 5310 times

Much better now.

boom 1.jpg (323.55 KiB) Viewed 5310 times

The mast-end of the boom was a bit trickier. Cut two lengths of aluminium flat stock, drilled holes, put them on the inside of the boom and put the bolts through. The aluminium pieces spread the load and are holding securely. Notice the double-sided tape? This was to insulate the stainless steel nut from the aluminium but also to hold the nut in place while I poked the aluminium piece into the tube and put the bolt through. That did not work very well with holding but managed to get the nuts on and tightened.

Reinforcing the inside of the boom at mast end.

boom 9.jpg (410.46 KiB) Viewed 5310 times

Insulated the stainless steel from the aluminium.

boom 5.jpg (404.48 KiB) Viewed 5310 times

Nicely finished.

boom 3.jpg (343.24 KiB) Viewed 5310 times

Other fittings I put the tape on contact surfaces and Tefgel on the nuts and bolts or on the pop rivets. With this piece, I measured the diameter of the holes in the boom and bought several sizes of rivets so that every hole had an appropriate sized rivet. Some of the old rivets simply pulled out because they were too small for the hole. I wanted to make sure if it had a rivet, it would be secure.

Another bit finished.

boom 2.jpg (339.15 KiB) Viewed 5310 times

Overall, I was very happy with the work done. Originally I did not think I would be able to repair the boom and it be strong but it seems to have come together well and I have not noticed the white aluminium corrosion like there was before.

troppo

[Phillip]

I use Duralac to insulate aluminium from everything else!

[SeaLady]

Get it professionally assessed then refurbished or replaced!!!!

But that requires more $$$ than elbow grease.

[Shaun]

Nice one Louis, looks like a sensible & comprehensive repair,
cheers

[Notlongjohn]

Troppo are you still answering questions?.wondering where your ronstan 423 boom cheeks and gooseneck
was sourced. I can't find anything similar on line except allmast stuff. Ronstan seems all lightweight.

[Troppo]

Sorry Notlongjohn, I am not much help to you. I did not need to replace the boom cheeks or gooseneck as the problem was corrosion of the boom itself. Once I cleaned the fittings they were good to go back on boom with suitable strengthening and fasteners.

I am not sure where you could get solid stuff from.

cheers

Troppo