GRP FILLER

[Guest]

Some of the screw about 75mm long that fix the rail stanchions to the deck have come loose on my RLM 27,there are four screw per base plate.
The screw holes appear to be solid in the boats side GRP moulding fender trim,my idea is to fill the hole with liquide grp and put the screw in so it all sets together.

My question is what sort of GRP liquid is best to use please help before someone falls overboard!

Or has anyone a better idea other than changing the boat!

 

[oldsaltoz]

G’day M newby.
I would not fill the holes with a liquid resin as resin alone is not very strong, however if you add some fibre filler it will be string and last a lifetime; you need to use an epoxy resin as this has a 40% better bond than wax / poly resin. If you drill out the old holes and fill them, then after the epoxy and fibre has gone off, re drill pilot holes for your screws and apply a little sealant. Job done.

Andavagoodweekend Old Salt Oz……

 

[vyv_cox]

Ask yourself why have these screws come loose? Probably because this is not an appropriate application for screws.
Ask yourself what are the consequences of using screws on fittings that might be asked to sustain heavy loads as the last prevention to falling overboard? Not nice.

I suggest that you use nuts and bolts with big washers to hold these fittings on. I don't think you can expect a bit of GRP filler to do anything more than a cosmetic treatment.

 

[Robin2]

I have used thickened West System epoxy to fix set screws (i.e. bolts threaded all the way) on my catamaran to hold some metal fittings. In my case it was impossible to get at the back of the fitting to put on nuts. West System claim this is a very strong way to hold fittings to a boat - I hope they are right !. Their recommended procedure is to drill a hole considerably larger than the set screw (1.5 times the diameter or maybe even more) so the epoxy has a large surface to grip. They recommend set screws instead of woodscrews because (I think) the wood screws are thinner for a given outside diameter. West System claim the set screw will break before the epoxy lets go!

Apparently it is possible to remove set screws from the epoxy by heating the screws - which softens the epoxy.

 

[trev]

I have found good old 'araldite' fine for such applications - but you must allow it to harden for at least a couple of hours on a warm day to ensure a good grip. - this business of being set after 10 mins is nonsense!
Clean out the holes or re-drill them slightly larger, then fill with the goo and wait for as long as poss before re-drilling and fixing. Use a little more goo on the screws.

Trev

 

[ccscott49]

If you cannot through bolt them, which is by far the best solution. Then drill the holes out twice the size of some stainless stell set screws, normal threads, not woodscrews, Fill the holes with a plastic metal type epoxy, metal repair stuff, allow to harden for two days, redrill the holes, the tapping size for the set screws, tap threads in these holes, clean the holes out. Dip the screws in normal epoxy resin mix, drive the screws in the holes, Hey presto, the screws will not come out, neither will the filler, if you can open out the holes a little underneath the surface, as a reverse cone, that would be even better. IMHO of course!

 

[Guest]

Keep in mind that Araldite is of course epoxy with some thickening. For small quantities this is by far and away the easiest way to do it but if the quantity is larger then get some epoxy and filler to make glue. It is mighty handy to have around for all sorts of repairs.