400: Bow roller material - Lagoon400

[meirriba]

Originally Posted by Sohum

Cool. Please follow up when complete. Specifically wondering how you secure the unit onto the cross beams outer edge. Last yr I went to remove mine so a shop could fabricate a flared side plate (cheeks wearing thin). The fasteners are internal hex bolts, very tight access inside the beam. long story short, I put this on the to do later list.
Good luck

On our boats, the fasteners everywhere, including front of beam are all rivets. No bolts.
I cannot imagine how can you access the beam from the inside to connect and tighten nuts to bolts coming from the outside.
Only way in my opinion is to put long bolts through the entire beam. With proper separation between metals (plastic sleeves) and maybe large collars between nut and beam to spread pressure (even 2, inner plastic and outer S/S against corrosion)

[crayiii]

This is what people are finding on 5 year old Lagoons.

[meirriba]

Originally Posted by crayiii

This is what people are finding on 5 year old Lagoons.

This is corrosion without any doubt...
Probably stainless steel unit attached to the aluminum beam by S/S rivets without taking any measures of separation.
Sad view��

[Icarus]

Use bolts, why using rivets?

[Icarus]

Another french quality product..

[meirriba]

Originally Posted by Icarus

Use bolts, why using rivets?

The fairlead is attached on the middle of the crossbeam. There is no easy access to the inside of the beam to secure the nuts.
Through bolts are also not very easy as under the oval crossbeam runs another metal square beam that strengthens the main beam so you will nead a very long bolts to secure the fairlead.
We are going to use monel rivets protected against corrosion by Tef-Gel or similar.

[Uncle Bob]

Originally Posted by meirriba

The fairlead is attached on the middle of the crossbeam. There is no easy access to the inside of the beam to secure the nuts.
Through bolts are also not very easy as under the oval crossbeam runs another metal square beam that strengthens the main beam so you will nead a very long bolts to secure the fairlead.
We are going to use monel rivets protected against corrosion by Tef-Gel or similar.

Wise move and I would be wary of adding too many more, lots of holes may lead to failures further down the track.

[Sohum]

Originally Posted by meirriba

On our boats, the fasteners everywhere, including front of beam are all rivets. No bolts.

All good? I randomly found this.

https://www.osculati.com/en/11006/al...-brass-rollers

[meirriba]

Originally Posted by Sohum

All good? I randomly found this.

https://www.osculati.com/en/11006/al...-brass-rollers

Not yet, but hopefully will be.
At this point of time, a new unit wad made, with side flaps to accommodate extra rivets.
The new fairlead is now being anodized in Athens, before addition if the roller.
Upon return to Preveza, the 'interesting' stage will be actual fitting on the crossbeam - hoping that the holes in the new fairlead are exactly where they need to be...

[meirriba]

Well, the saga is finished.
New fairlead installed. Made of Aluminium (as was the original one that committed suicide by drowning...)
I have seen unhappy pictures of stainless steel fairleads mounted on Aluminium crossbars and the resulting corrosion.
Have used 15 rivets in lieu of 7 on the old one. Two extra rivets on the front flap, six rivets on the added side flaps (three per side).
We have used Monel rivets, 6.4mm x 18mm. Original rivets were 5.8mm Aluminium (I do not know the length used).
To defer corrosion the rivets were covered by 'Anti-Seize' paste by Yachticon.
The roller is Acetal (engineering thermoplastic). AKA Delrin by Du-Pont.

As of today, I have not received any response from Lagoon as to an availability (or cost) of a replacement unit. Query was sent about a month ago.

[Spot]

The new roller looks very good with the additional side pieces and rivets as well as not looking too overworked compared to the original one earlier in the thread.