Filling transducer holes

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oakleyb

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I've been quoted £750 to glass over 3 transducer holes and as a result seriously thinking of doing these my self. I've read up on the subject and it seems to be fairly easy to complete - my only concern is how do I deal with curing and cold temperatures. Would look to complete work over winter when ashore.

Is it a diy job ?
 
oakleyb said:
I've been quoted £750 to glass over 3 transducer holes and as a result seriously thinking of doing these my self. I've read up on the subject and it seems to be fairly easy to complete - my only concern is how do I deal with curing and cold temperatures. Would look to complete work over winter when ashore.

Is it a diy job ?
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I think it's a DIY job, i have one to fix later this month. Just ordered the materials online from East Coast Fibreglass http://www.ecfibreglasssupplies.co.uk/

You don't want to be too cold with polyester resin, it's designed for 20c. You're only working with small areas and can do some of it from the inside, so should be able to get some heat into the inside of the boat. Maybe cover the area outside and heat that too ?
 
Easiest way is to laminate a patch inside with epoxy and glass cloth, then fill the outside hole. Cut a circular spacer out of ply about 6mm thinner than the depth of the hole and stick that in with epoxy then laminate with epoxy/glass up to level of hull. Prime and antifoul.
 
PaulRainbow said:
My boat was built with polyester, there is absolutely nothing wrong with using it to effect a repair.
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That sound appear logical but it isn't true.

New polyester doesn't stick half as well to cured polyester as epoxy does.

I've been given to understand that when you're laying up a polyester moulding, you should never let the layer below cure completely. This ensures that the new layer you apply bonds chemically with the underneath layer.

This what I've heard anyway.

Epoxy is the way ahead.
 
john_morris_uk said:
That sound appear logical but it isn't true.

New polyester doesn't stick half as well to cured polyester as epoxy does.

I've been given to understand that when you're laying up a polyester moulding, you should never let the layer below cure completely. This ensures that the new layer you apply bonds chemically with the underneath layer.

This what I've heard anyway.

Epoxy is the way ahead.
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Plus 1 re polyester resin. Yet polyester while no where near as good as epoxy can do an adequate job. I would not do the ply plug thing. I would just use lots of layers of cloth or Chopped strand mat. The trick is to chamfer the holes so lager diameter of cloth fits into the chamfer both ont he inside and outside with smallest diameter in the middle of the hulkl material. This way polyester resin sticks to itself when green forming a shape a bit like a yo yo. With hull material sandwiched between. So that even with complete non sticking of the new resin to the old it can not fall out.
I would use heating from inside on the hull and perhaps a tent or similar over the repair on the outside. Hotter equals quicker/ better hardening of epoxy or polyester.
I filled my log hole many years ago and can see no signs of the repair now. very easy very successful and certainly not 750 squid for 3 prices. Indeed I( could come from Oz and do it for that price) olewill
 
thanks for the replies, if i end up with lets say 4 layers of glass to fill the hole, can i add these all in one sitting ie, wet the first then second and so on ?
 
john_morris_uk said:
I've been given to understand that when you're laying up a polyester moulding, you should never let the layer below cure completely. This ensures that the new layer you apply bonds chemically with the underneath layer.
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That is correct, you also have to be careful not to put too much on too soon, as the heat buildup can be significant.

That said, i doubt that Westerly managed to build my boat in one go, without letting some of the layup fully cure. All manner of bulkheads etc would have been glassed in later and they are still there. I shall grind and taper the hole and fill entirely with mat and resin, as Will describes in post #7
 
I've done many small fibreglass repairs using repair kits from Halfords out of ignorance. They've all lasted well and caused no problems but I would use epoxy resin now. The cost difference is not much for a small area. The secret with grp work is preparation. Have everything cut to size in advance and laid out ready for use as once started there is little time. It's worth getting some acetone to clean brushes and hands (it's a sticky business) and wear overalls and rubber gloves. I used to use the disposable ones but found them prone to splitting so now use marigolds. Good luck.
 
Just done 4 on mine. Download the west system guide as it will show you the correct procedures. You need a 12to1 chamfer on the outside and as close to it as you can on the inside too. I used 6 layers of woven cloth on each side in ever decreasing circles with sp106 epoxy. It does end up as a large repair but it's the only way you can be sure of maintaining the strength.
 
matthewriches said:
What's the lift out costs where you are Paul? I've got about 5 seacocks to fill and 2 thru hull fittings that need blanking. Got more holes in my Fairline than I'm comfortable with!
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Until the end of the month, Summer special, £21 a metre. Lift, scrub, week on the hard, lift back in.
 
Bobc said:
Why not just stick some transducers in the holes.
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'Twas my thought too.

Even the echo sounder works better when it's mounted properly through-hull.

Last count we've got 17 holes through our hull. (That's including the rudder and prop shaft. ) Good quality sea cocks for emergency closure, but 99% of the time most of the sea cocks are open.
 
Tammany said:
Just done 4 on mine. Download the west system guide as it will show you the correct procedures. You need a 12to1 chamfer on the outside and as close to it as you can on the inside too. I used 6 layers of woven cloth on each side in ever decreasing circles with sp106 epoxy. It does end up as a large repair but it's the only way you can be sure of maintaining the strength.
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On most hulls there is very little loss of strength putting a relatively small hole in the laminate in that area of the hull. While the procedure you followed makes the repair look seamless with the original laminate, it really is not necessary. The important thing is to make the hole watertight and ensure that your patch does not fall out. So a sound patch on the inside together with a secure fill from the outside is more than strong enough.
 
john_morris_uk said:
'Twas my thought too.

Even the echo sounder works better when it's mounted properly through-hull.

Last count we've got 17 holes through our hull. (That's including the rudder and prop shaft. ) Good quality sea cocks for emergency closure, but 99% of the time most of the sea cocks are open.
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I currently have an in hull depth transducer, through hull log and a redundant through hull, possibly for an old depth transducer. I'm replacing the log with a triducer and ditching the in hull transducer.

This leaves me with a redundant through hull, that looks like it's been there since the boat was built and the plastic inside the hull is rather degraded.

It's only about an inch diameter, so i'll be tapering the hole and making a suitably strong repair. I most certainly will not be grinding a 12:1 area of my hull away though.
 
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