warrior40
New member
Whats the best way to fill a hole left by an old transducer on a GRP yacht?
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Best way to fill old transducer hole?
- Thread starter warrior40
- Start date
snowleopard
Active member
sing a small angle grinder, bevel the skin on the outside for about 2" all round. blank off the inside with a piece of stiff polythene (cut from an old bucket etc)
apply glass fibre mat & resin to bring it proud of the hull.
when set, grind back level.
for extra security, then grind the inside and apply a patch there.
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apply glass fibre mat & resin to bring it proud of the hull.
when set, grind back level.
for extra security, then grind the inside and apply a patch there.
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BarryH
Active member
I'm gonna hate myself for saying this............with an old transducer!!
No but seriously. Better to start on the inside then do the stuff, already mentioned, on the out side. Once its all done finish off with a gel coat and then treat as you would car paint. Fine wet and dry then a cutting compound to bring the shine back. Chances are it'll get covered by antifoul anyway.
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No but seriously. Better to start on the inside then do the stuff, already mentioned, on the out side. Once its all done finish off with a gel coat and then treat as you would car paint. Fine wet and dry then a cutting compound to bring the shine back. Chances are it'll get covered by antifoul anyway.
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oldsaltoz
New member
G'day warrior40,
Another method that may save you some work.
Feather the outside of the hole with a grinder, without grinding the area outside the hole.
Get an off-cut of Formica or similar sheeting that has a high gloss, apply some wax (Not silicon) as a release agent to stop the resin sticking to it; place this over the hole and wedge it into place with a prop or two.
From inside, apply 4 coats of epoxy resin (or gelcoat about 3 mm thick), let this set, then apply fibreglass and resin to build up level with the inside of the hull, also apply at least 2 layers of glass over the hole that overlap the edge of the hole by at least 50 mm; let this set.
Remove the Formica and you will have a nice smooth finish on the outside, no sanding to do....
Hope this helps.
<hr width=100% size=1>Andavagoodweekend, Old Salt Oz /forums/images/icons/cool.gif
Another method that may save you some work.
Feather the outside of the hole with a grinder, without grinding the area outside the hole.
Get an off-cut of Formica or similar sheeting that has a high gloss, apply some wax (Not silicon) as a release agent to stop the resin sticking to it; place this over the hole and wedge it into place with a prop or two.
From inside, apply 4 coats of epoxy resin (or gelcoat about 3 mm thick), let this set, then apply fibreglass and resin to build up level with the inside of the hull, also apply at least 2 layers of glass over the hole that overlap the edge of the hole by at least 50 mm; let this set.
Remove the Formica and you will have a nice smooth finish on the outside, no sanding to do....
Hope this helps.
<hr width=100% size=1>Andavagoodweekend, Old Salt Oz /forums/images/icons/cool.gif
warrior40
New member
Well I might well leave the old transducer there, but as it has been redundant for some years, even before my ownership, I do not know its 'pedigree'. I will try these ideas out, I think, they all sound like good advice, cheers V. much.
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Aja
Well-known member
Did this 2 years ago.
As per oldsaltoz - piece of polythene or similar then cut plenty of circles slightly larger than the hole to be filled (they shrink ever so slightly) - and work from the inside.
Wet out the mat then poke with brush into the hole ensuring no air bubbles - continue to build up the thickness until flush with the inside of the hull.
Then apply 2 or 3 layers of mat which extend from the hole by at least 3". Remeber to chisel or grind away any gelcoat on the inside of the hull back to laminate to ensure proper binding.
Once cured remove polythene from outside of hull, prime and antifoul. No filling necessary. Took me about an hour all in. Messiest bit was cutting the mat into circles!
Regards
Donald
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As per oldsaltoz - piece of polythene or similar then cut plenty of circles slightly larger than the hole to be filled (they shrink ever so slightly) - and work from the inside.
Wet out the mat then poke with brush into the hole ensuring no air bubbles - continue to build up the thickness until flush with the inside of the hull.
Then apply 2 or 3 layers of mat which extend from the hole by at least 3". Remeber to chisel or grind away any gelcoat on the inside of the hull back to laminate to ensure proper binding.
Once cured remove polythene from outside of hull, prime and antifoul. No filling necessary. Took me about an hour all in. Messiest bit was cutting the mat into circles!
Regards
Donald
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yoda
Well-known member
I blanked a hole a few years back with 2 nice brass discs through bolted and bedded on a suitable sealant. Leaves a slight bump on the outside but I have greater confidence in that than my ability to lay up grp on the underside of the hull where gravity works against you. Worth thinking about and also very quick to achieve (between tides)
Yoda
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Yoda
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Re: West System Video
One of the West System training videos shows how to repair small holes like this.
Measure the hull thickness and if plugging just from the outside then grind back around the hull enough to create a 12 to 1 gradient. Then pre-cut many concentric patches getting progressively smaller. The largest patch should be applied first.
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One of the West System training videos shows how to repair small holes like this.
Measure the hull thickness and if plugging just from the outside then grind back around the hull enough to create a 12 to 1 gradient. Then pre-cut many concentric patches getting progressively smaller. The largest patch should be applied first.
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