Fiberglass coating

[haydude]

Hi,

I have an area inside by boat where the fibreglass is bare/exposed, clearly this is an area that is not supposed to be normally used so the manufacturer did not put any finish on it, however there are hoses and wires running through it and since it is hard to reach, whenever I put my hands inside for a job I end up with glass fibres piercing my hands and elbows.

What paint or sealer would you recommend to go over it and seal it once and for all?

 

[KenMcCulloch]

Hi,

I have an area inside by boat where the fibreglass is bare/exposed, clearly this is an area that is not supposed to be normally used so the manufacturer did not put any finish on it, however there are hoses and wires running through it and since it is hard to reach, whenever I put my hands inside for a job I end up with glass fibres piercing my hands and elbows.

What paint or sealer would you recommend to go over it and seal it once and for all?

What you need is a flowcoat which is polyester resin with a sort of wax in it which allows it to cure even when exposed to air. A good chandler should be able to supply the necessary components (resin, wax, catalyst)

 

[Quandary]

Coating

'Flow coat' which is used to coat lockers etc, normally white, it is basically thinned gel coat modified to let it go off like paint, from any GRP specialist.

 

[sailorman]

Hi,

I have an area inside by boat where the fibreglass is bare/exposed, clearly this is an area that is not supposed to be normally used so the manufacturer did not put any finish on it, however there are hoses and wires running through it and since it is hard to reach, whenever I put my hands inside for a job I end up with glass fibres piercing my hands and elbows.

What paint or sealer would you recommend to go over it and seal it once and for all?

why not just sand it down

 

[haydude]

why not just sand it down

Because it would be a big job, in an unaccessible place making lots of dust.

 

[haydude]

'Flow coat' which is used to coat lockers etc, normally white, it is basically thinned gel coat modified to let it go off like paint, from any GRP specialist.

Thank you! Flowcoat it is then!

 

[nimbusgb]

If you mean just surface fibres from exposed glass flocoat will seal it but I doubt if flocoat is going to cover the sharp edges of fibreglass laminations. Suspect you will end up with a nice clean locker interior ....... which still grabs fingers.

 

[sailorman]

Because it would be a big job, in an unaccessible place making lots of dust.

hand sanding

if your unable to do that how will you brush the flocoat ??

 

[status]

Sand back any sharp pointy bits of resin, wipe it down and paint it.

Flow coat is good, hard wearing, resistant to water oils etc. but a pain to apply as has to be mixed with catalyst etc.

You suggest this area is out of the way and out of sight so something like bilge paint may be an easier option, even household gloss.

Stuart

 

[Alcyone]

I've used this, from CFS in the past. Good folk, imo.

http://www.cfsnet.co.uk/acatalog/CFS_Catalogue__White_Topcoat_154.html

 

[carrswood]

Woudn't Danboline do the same job?

 

[Quandary]

Rough edges

If the fibres are really spiky, flowcoat might not be enough but first you can mix resin (poyester or epoxy) with filler to any consistency you can work with and brush it into the sharp corners, then cover with flowcoat for a smooth finish which is very durable.
Flowcoat is good over raw plywood too, all the voids in my boat and most of the lockers are finished this way. Inthe bilges it is brown, otherwise white.
It is significantly more durable and water resistant than Danboline.

 

[sailorman]

KISS

If the fibres are really spiky, flowcoat might not be enough but first you can mix resin (poyester or epoxy) with filler to any consistency you can work with and brush it into the sharp corners, then cover with flowcoat for a smooth finish which is very durable.
Flowcoat is good over raw plywood too, all the voids in my boat and most of the lockers are finished this way. Inthe bilges it is brown, otherwise white.
It is significantly more durable and water resistant than Danboline.

 

[oldsaltoz]

Hi,

I have an area inside by boat where the fibreglass is bare/exposed, whenever I put my hands inside I end up with glass fibres piercing my hands and elbows.
What paint or sealer would you recommend to go over it and seal it once and for all?

As others have posted, flowcoat will provide a good smooth surface, however you will need to some preparation, a quick rub with a 40 grit sandpaper will make short work of any sharp bits and remove any loose fibres. Then wipe it clean.

Flow coat comes in many colours, you can buy it ready mixed or make your own by adding colour to the resin and a small amount of filler to get the thickness you want.

Take care not to add too much catalyst, poly resin needs between one and up to 2% catalyst added to start it curing, however flow coat may have up to 50% solids so adding 1% to this will be the same as adding 2% to resin, that will go off in a short time.

Use shallow wide containers to help dissipate the heat generated when the catalyst is added. Throw away latex gloves will help, put two on each hand so you can pull one off when it gets too sticky or your mobile phone goes off.

Don't waste time trying to get a perfect finish, get as much area covered as you can in the shortest time, the flowcoat is self levelling to some degree so don't get cought with resin going off.

Cheap rollers (80 mm) or 3 cut from a wider roller can be thrown away when finished, same for brushes,

Mix up the flowcoat really well before you add the catalyst, a drill is good for this. Acetone will clean off any tools or spills, keep the used acetone and stand it overnight, any rubbish will sink leaving clean fluid on top.Hope this helps

Avagoodweekend......

 

[snowleopard]

'Flow coat' which is used to coat lockers etc, normally white, it is basically thinned gel coat modified to let it go off like paint, from any GRP specialist.

You can make your own flowcoat by adding 'wax in styrene' to ordinary gelcoat. Thinning can make it run off so only add thinners (styrene) if it is too thick to spread.

The wax is to make a film on the surface which stops it remaining tacky.

 

[Quandary]

Stupid; Who, me?

Contrary to the suggestion above I do believe in simplicity and I am not stupid.
When I put the bulkheads in to my Achilles 24 hull, many many years ago, I finished up with some nasty fibre ends as described by the OP, sanding was not always easy as they were usually in tight awkward corners and it proved easier to overcoat them. ( you don't get the problem where access is good). When I fitted out the next boat I had learned to be more careful, but you can find the problem when you stretch your hand into awkward corners of lots of professionaly built British boats from the seventies. In Scandanavian boats where all unfinished surfaces are flowcoated you have a clean smooth easily maintained surface even in the most awkward corners. The OP would not have asked the question if all that was needed was a rub with sandpaper.
When I give an opinion it is normally based on personal experience and is usually done in the hope that that experience or knowledge could be useful, it is not an ego trip for me so I don't need to post all the time on every subject, and I recognize that there may be others with different advice which the questioner can also consider.

 

[Avocet]

...Throw away latex gloves will help, put two on each hand so you can pull one off when it gets too sticky or your mobile phone goes off.
...

THERE's a guy whose been there before!!!

There's just nothing worse than being up to your elbows in goopy resin and having the phone ringing in the top pocket of your overalls!

Only (sensible!) comment I'd add is that if the surface is vertical (or nearly so, the flowcoat will try to run down it. There will be a big temptation to spread it on as thick as possible to cover the spikey bits, but that's likely to lead to big pools of it at the bottom of the vertical surface!

Also, I'm not sure, but I think that if you are thinking of applying several coats, (to avoid the runs, so to speak), it's probably better to use ordinary gelcoat with a tiny bit of pigment in it and ONLY use "Flowcoat" for the last coat. This is because (as has been said), Flowcoat is gelcoat with wax in styrene added. As it sets, the wax rises to the surface and excludes the air - allowing the surface to dry properly rather than remain tacky. I don't know whether trying to put a second coat over the flowcoat (which will then have a waxy surface) would work terribly well, but I've not tried it!

 

[oldsaltoz]

QUOTE:
Also, I'm not sure, but I think that if you are thinking of applying several coats, (to avoid the runs, so to speak), it's probably better to use ordinary gelcoat with a tiny bit of pigment in it and ONLY use "Flowcoat" for the last coat. This is because (as has been said), Flowcoat is gelcoat with wax in styrene added. As it sets, the wax rises to the surface and excludes the air - allowing the surface to dry properly rather than remain tacky. I don't know whether trying to put a second coat over the flowcoat (which will then have a waxy surface) would work terribly well, but I've not tried it! END QUOTE.

It's OK to apply extra coats provided the original coat has not fully cured, even then a wash with Acetone and a light sand will ensure no problems.

Avagoodweekend......