Sealing fibreglass after drilling

[BogMonster]

Just did a search but couldn't find the answer to this

I went down to check on the RIB last night as it was blowing a gale from a bad direction and it was really bouncing around, to the extent that the stern mooring point on the tube was deforming the whole tube. Bow was OK as 1) it was the sheltered end and 2) there are nice big stainless rings inside and outside to tie to. So I figure it would be worth putting something similar on each side of the transom, to put a second line on to, so it provides a backup in case the one on the tube lets go (the previous owner told me that one of them did come off once when somebody else was tied up alongside him). I tied it back to the A frame for security last night just in case (and it was fine this morning anyway), but this isn't ideal.

What (if anything) do you need to do after drilling the transom to seal it against any water ingress? or don't you need to do anything? if you should seal around the bolt/washer, what with? Maybe I am being paranoid but lots of stories about water getting into fibreglass worry me slightly - obviously this will be above the waterline but it's still going to be pretty wet where it will be on the outside of the transom.

Thanks

[Scary Des]

Stephen are you on a pontoon Des

[Alice]

White Sikaflex. A squirt bolt head and nut end. Do it up and wipe off the excess with a bit of thinners.

[BogMonster]

Originally Posted by Alice

White Sikaflex. A squirt bolt head and nut end. Do it up and wipe off the excess with a bit of thinners.

Thanks, I was thinking maybe Sikaflex or some similar sort of sealant, just wondered if it was necessary.

At the moment it is alongside a visiting slightly broken yacht, but yes it will be moored to the pontoon once the yacht is taken away to be sent home on a cargo vessel. Why? The pontoon is quite big so doesn't move round much but the waves coming round the end in the northerly wind last night were enough to make the RIB buck a fair bit! Normally the wind is mainly westerly here in which case no problem, but it is N/NE winds that interfere with most of the mooring points round here because most are built with shelter from the west/north and entry from the east end.

[Scary Des]

The reason I ask is that unless it is very sheltered pontoons aren’t the friendliest of places for any boat in a storm imho it is far better (if you have the choice) to put the boat on a swing mooring because the boat is always head to weather and can’t rub against anything Des

[jwalker]

The sealer at both ends is probably ok but I always mix up a little resin and flood the inside of the hole a couple of times with a wee watercolour brush to seal the wood grain and the disturbed fibreglass ends. It's sometimes surprising how much resin can be sucked up.

[BogMonster]

I see what you mean - but at the moment it's the only option. A few of us are working on something else for storage in the long term though, and some way of holding the boats off so they aren't rubbing against anything has been discussed. Designers are Messrs Heath and Robinson though

JW thanks - I don't have any at the moment but I don't have any ring bolts either so I need to "acquire" both at minimal expense!

[ADS]

I would put abit of carpet over the tubes to protect them or you could thread the stern line through a bit of hose pipe. Keep your tubes pumped up hard and go over board with the fenders, old tyres tied to the pontoon work equally as well.


Alex

[Scary Des]

Originally Posted by BogMonster

....Designers are Messrs Heath and Robinson though.....

Ahhh fine designers often use them myself

One of the most annoying things with ribs is that you will damage the tubes if you run a working rope over them the front ‘d’ ring is generally OK but any fixing at the back can cause problems and touch the tubes if you are using a mooring line at right angles to the centre line of the boat.
I can’t explain this well but here's a JW inspired pic. I haven’t shown the springs which are another issue all of their own Des.

[Alice]

Originally Posted by jwalker

The sealer at both ends is probably ok but I always mix up a little resin and flood the inside of the hole a couple of times with a wee watercolour brush to seal the wood grain and the disturbed fibreglass ends. It's sometimes surprising how much resin can be sucked up.

Bit of a sod if you ever want to remove it though!

[pressman]

Originally Posted by BogMonster

Just did a search but couldn't find the answer to this

I went down to check on the RIB last night as it was blowing a gale from a bad direction and it was really bouncing around, to the extent that the stern mooring point on the tube was deforming the whole tube. Bow was OK as 1) it was the sheltered end and 2) there are nice big stainless rings inside and outside to tie to. So I figure it would be worth putting something similar on each side of the transom, to put a second line on to, so it provides a backup in case the one on the tube lets go (the previous owner told me that one of them did come off once when somebody else was tied up alongside him). I tied it back to the A frame for security last night just in case (and it was fine this morning anyway), but this isn't ideal.

What (if anything) do you need to do after drilling the transom to seal it against any water ingress? or don't you need to do anything? if you should seal around the bolt/washer, what with? Maybe I am being paranoid but lots of stories about water getting into fibreglass worry me slightly - obviously this will be above the waterline but it's still going to be pretty wet where it will be on the outside of the transom.

Thanks

The best way is to put some epoxy in behind the plates or washers, clean off excess before curing.

Araldite can be usefull for this also.

[roycruse]

Originally Posted by Alice

Bit of a sod if you ever want to remove it though!

I think he means let the resin set - before putting the bolt in

[Alice]

Originally Posted by roycruse

I think he means let the resin set - before putting the bolt in

Ah OK! I had visions of chainsawing the transom to get the engine off!

[codprawn]

Or you can coat the bolt in silicon grease or similar - should just unscrew later.

[jwalker]

Originally Posted by Alice

Ah OK! I had visions of chainsawing the transom to get the engine off!

I'm beginning to think you really are a woman!

[jwalker]

Originally Posted by codprawn

Or you can coat the bolt in silicon grease or similar - should just unscrew later.

Never put silicon grease near anything where there is a remote possibility you may want something to adhere in the future.

Like blocking the hole up again or Sikaflexing.

[codprawn]

Originally Posted by jwalker

Never put silicon grease near anything where there is a remote possibility you may want something to adhere in the future.

Like blocking the hole up again or Sikaflexing.

That is the idea!!! You can put a bolt into a hole - epoxy it in - then you can unscrew the bolt and you have a nice threaded insert.

Of course you have to make sure the silicone is only on the bolt!!!

[roycruse]

Originally Posted by codprawn

That is the idea!!! You can put a bolt into a hole - epoxy it in - then you can unscrew the bolt and you have a nice threaded insert.

Of course you have to make sure the silicone is only on the bolt!!!

And you've actually done this !!!

I cant believe the thread of a bolt is uniform enough for this to work - any damage to the bolt or uneveness would result in the bolt never coming out or you cracking the epoxy.

[Dirk Diggler]

Originally Posted by roycruse

And you've actually done this !!!

What do you reckon?

[BogMonster]

Originally Posted by Scary Des

Ahhh fine designers often use them myself

One of the most annoying things with ribs is that you will damage the tubes if you run a working rope over them the front ‘d’ ring is generally OK but any fixing at the back can cause problems and touch the tubes if you are using a mooring line at right angles to the centre line of the boat.
I can’t explain this well but here's a JW inspired pic. I haven’t shown the springs which are another issue all of their own Des.

Mine has a stainless ring on the inside and outside on the bow, at the moment I am using the inside one but I hear what you say about tube damage... so next time I will use the outside one as at the moment the bow line is just out over the tube.

There are rubber (or something like that) ones glued to the tubes fore and aft on each side but it is these ones I am worried about coming off - so I think a good eye bolt on the outside of the transom each side of the motor would be the answer. Not sure how I am going to fit this in with the aux engine when I get it but as I don't have either an engine or the eye bolts yet I have some thinking time available

I suppose the best compromise might be to use the ones on the tubes but have a second line back to a more substantial stainless loop on the transom, just in case the main one broke free. That way there would be nothing under load rubbing on the tubes, just the backup line, and it would only come in to play if the worst happened. It does get pretty lumpy here even at sheltered moorings, as wavelength will testify it is a fairly windy part of the world!