Topic: Rub Rail Attachment Repair

Hi Everyone,

I just discovered a new problem as I finish up the re-fit of my boat......the aluminum rub rail that covers up the hull-to-deck joint is loose and will obviously leak through the holes where it was fastened to the boat.  I'm trying to figure out the best way to re-attach and seal it.  the old fastenings were aluminum rivets......but it doesn't seem like they had adequate holding power.  I'm wondering if screws might be the best option.......however, the holes for a number of the 3/8" rivets seem like they've been expanded some and I'm concerned that I'd have to increase the size of the screw to something that would be sort of ridiculous.  Now, I'm thinking maybe I could use 3/8" through bolts, as a lot (if not most) of the back sides are accessible. 

If anyone else has come up with a great way to fix this problem, I'd love to hear about it.  Thanks.


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Re: Rub Rail Attachment Repair

The aluminium rub rail is only for cosmetic purpose. In my case the rub-rail was fix with stainless steel screws.

For the leaks: I suggest that you remove the aluminium rub rail, clean the hull to deck joint and fill with 3M 4200 and re-install the aluminium rub rail with screws, clean the excess 4200.

Co # 158

Contessa 26 #158
Sun Wave
Montreal QC

Re: Rub Rail Attachment Repair

There is no quick fix, no easy fix - the job needs doing right.

You wont be able to get screws to hold reliably in sealant so will have to glass up all the holes and redrill them if you go down that road. 

Through bolting will work but unless the hole is in good tight condition, even a light bump on the rubbing strip will be likely to break the bond between the sealant and the bolt thread and start a leak.  If the strip gets a severe ding or catches on something, you are likely to get a lot of damage round the bolt holes

Personally, I'd get aluminium closed end pop rivets with an aluminium mandrel (don't mix metals due to corrosion) and install each with a dab of sealant.  If the hole is slightly enlarged and there is inside access, a close fitting stainless washer can be used on the inside, but badly wallowed out holes will need glassing up and redrilling.  The mandrel holes in all rivet heads must be plugged or carefully filled with sealant to minimise corrosion which would weaken the body of the rivet. Make sure you use countersunk head rivets and that the head ends up slightly below the rubbing strip surface so a ding that compresses the sealant slightly doesn't force the rivet in, breaking the bond between it and the hole sides and starting a leak.

Aluminium is not an easy metal to adhesively bond due to the oxide layer that rapidly forms on freshly cut surfaces. If you rebed the whole rubbing strip, you will need to sand the back of it to clean metal, then after cleaning and degreasing, lightly sand the surface and IMMEDIATELY smear with a very thin coat of sealant to get a good bond.  Once that's done, you have as long as that coat remains even slightly tacky to get it bedded in place with additional sealant.  Another approach is to sand through a puddle of G4 pond sealer  (to exclude atmospheric oxygen) then wipe off leaving a trace behind as a primer.  Its polyurethane based so polyurethane sealants bond well to it while its still tacky. If you let it dry past that you will need to sand it off and start over.

Re: Rub Rail Attachment Repair

This is a fun project.  And thus far I have been fortunate to have other projects with higher priority. 

Ian is right -- reattaching the rub rail may prove to be a bit of an adventure and he has given some great information about how to achieve success as you do the work.

For interest, the rub rail on my boat was installed using small slotted oval-head screws -- no rivets.  Sealing this area is the challenge.  On my boat there is a foam gasket between the aluminum and the fibreglass boat.  Were I concerned about leaks from the rail I would begin with a low-effort fix;  specifically I would pull each screw (one at a time) and re-install them along with a daub of 4200.  I would avoid shifting the aluminum piece relative to the boat to preserve whatever seal remains between he aluminum and the underlying glass.  This strategy would stop all (or most) leaks through the screw holes so that I could rule out these holes as the source of the leak.

I have a question:  was the rub rail leaking?  My experience with leaks in this area has directed me to the bolts along the traveller.  Given how much of a PITA it is to remove the nuts from the bolts which secure the traveller I opted to drip a little of Captain Tolley's Creeping Crack Cure around the heads of each of the traveller bolts.  I give the cure a couple of minutes to penetrate and then wipe off any excess.  For my boat this immediately solves the leak problem for a season or two.  Specifically, I go from 2-4 litres of water in the quarterberth lockers following a rainstorm, to none -- dry lockers.  When the leak reappears I apply more Creeping Crack Cure and the leak disappears again.  This leak reappears every two- to three- seasons.   

Good hunting....


My experience with leaks in this area has pointed to the travellers and not the rub rail.

Re: Rub Rail Attachment Repair

I never reinstalled the rubrail when installing the new genoa tracks.   I glassed in the hull/deck joint (including c-sinking and filling all rubrail screw holes) after digging and picking and removing all traces of what was appeared to be a butyl type sealant.  Just couldn't bring myself to put more holes in my boat.  No leaks....

Re: Rub Rail Attachment Repair

The problem with that is being sure you have a bulletproof structural joint between the hull and the deck without the rivets or screws.  You don't want the deck peeling up from the hull due to shock loading on the genny cars and inadequate bonding.

Re: Rub Rail Attachment Repair

on my 74 taylor boat, hull/deck attachment was accomplished with 3/8" rivets.  i didn't remove these.......  just the screws for the rubrail.....................................

Re: Rub Rail Attachment Repair

Like Stephan' Contessa, my hull to deck joint is made with rivets and the purpose of the rub rail is purely cosmetic.
You can look at the website of Stephan for pictures of the joint.

And no you will not rip the deck because a poorly bonding of the rub rail.

Contessa 26 #158
Sun Wave
Montreal QC

9 (edited by Ian Malcolm 2014-12-25 06:06:30)

Re: Rub Rail Attachment Repair

I believe best practice would be to *REPLACE* existing joint fastening rivets if glassing up the joint without grinding out and structurally taping it.  You don't know how badly corroded the existing rivets are and as Epoxy or polyester resin isn't as resilient as sealant, and salt water aluminium corrosion invariably expands many times the volume of the parent metal, if you seal up existing active corrosion, the forces generated can split the joint.

J Rogers (UK) boats have an upturned flange that is purely resin bonded - no rivets at all, with the joint capped by the toe rail and usually no rubbing strip whatsoever.   IMHO a preferable method of construction, but if the joint does partially fail, we tend to have trouble with the encapsulated wooden stringer  the edge of the deck sits on.

Re: Rub Rail Attachment Repair

Very interesting ideas and helpful suggestions.  Really appreciate everyone taking the time to comment on this one.  It's been a big help.  I'm going to do a quick fix for this time just because after a 3 year full-time refit, I'm worn out with any further big projects and don't want to delay the "big trip" any further.  I'm going to put "fixing this right" on the future to do list.  thanks everyone.