Fibre glass advice please!

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Arnold9801

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A few weeks ago I adapted a fibre glass fishpond for it to be used by our new ducks. This only involved me fitting a bottom drain on its flat floor.

During the week it started leaking and this afternoon we disconnected it from the waste outlet pipe, lifted it out of the ground only for it to crack. The photo shows the fracture.

My question is could this be easily repaired? I've never used fibreglass before.

Advice would be appreciated.

Arnold9801
 

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A few weeks ago I adapted a fibre glass fishpond for it to be used by our new ducks. This only involved me fitting a bottom drain on its flat floor.

During the week it started leaking and this afternoon we disconnected it from the waste outlet pipe, lifted it out of the ground only for it to crack. The photo shows the fracture.

My question is could this be easily repaired? I've never used fibreglass before.

Advice would be appreciated.

Arnold9801
Yes there is no problem with a repair, there is a fibre glass dealer down your way , I will find the name of them.
 
Yes give the area a good clean and make sure to give a light sanding to give it a key, your repair will be on the underside as the inside of the pond will be the top coat when it was made. you can cover the crack on the inside with masking tape if you buy from cfs they will give you all the info req for the mixing , buy some acitone as well for cleaning.
 
Yes give the area a good clean and make sure to give a light sanding to give it a key, your repair will be on the underside as the inside of the pond will be the top coat when it was made. you can cover the crack on the inside with masking tape if you buy from cfs they will give you all the info req for the mixing , buy some acitone as well for cleaning.
Thank you for that advice. Do I have to apply fibreglass and heating on the smooth top coat side? Also, would you fibre glass over the plastic drain or take it out whilst I repair it?
 
Repair both sides - it'll delaminate if you don't. Acetone? Yes, but buy throw away brushes as well. It's a pig to clean.
Thank s for your advice. I’m shortly going to get the materials and as I said, I’ve never fibre glasses before. I take it you sand both sides? Also will it be dry/set in a day? And should I fibre glass over the drain outlet or remove it and then repair it putting the drain back afterwards?
 
Key both sides. I would be tempted to go over the hole and recut it. In an ideal world you'd probably get some gel coat, but it's expensive for what little you'd need. Try to get hold of a small amount of glass tissue for the final coat - it'll give you a better finish and thus a better repair. You've not used GRP before, so when you do the job stipple it until the glass fibre goes virtually transparent - if you can still see it clearly you haven't wet it and stippled it for long enough..
 
Fibre glass work is quite easy but the curing times and perhaps quality(?) are dependant on temp, given the time of year it might be a struggle to do outside,,,people who know about these things will no doubt advise. It looks like a horrible old thing thats for sure and if I was doing it I think it would get a good sanding off on both sides, after drilling a hole at each end of the split and really opening up the crack, that way you can get glass tape or matting well down into the crack from both sides as well as on the faces, I might also be tempted to glass over that drain and then cut a new one a little away from the original if possible?
 
My gut feeling is the drain is the source of the problem because the glass fibre the pond is made of looks horribly thin from the photo, and with all due respect you quite likely initiated the cracks when you cut it. The further problem is that unless you have that drain connected to something whenever you use it a cavity will develop under that area of the pond and lead you back to the problem you now have.

As evrything is so thin I would get rid of that drain altogether - fibreglass over it totally and get a small pump for emptying. Another downside of the drain is that currently you know where it is but in 5 years?? And then you dig through that period of detritus in the pond bottom and the drain will block - guaranteed!
Rob
 
I would really rough up the edges of the crack with something like a rasp or surform. I think the build is probably resin poor and the more resin you get into the original fibers the better.

Also put a square of reinforcement glass top and bottom of the drain to reinforce.

Cheers James
 
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ALSO: I know nothing of ponds (but a bit about G-F ing). Is it possible that if the OP didn't start the crack when installing that drain but instead, if the area under the GF was not completely flat then the weight of the water after filling started that crack around an area that wasn't fully support by the earth underneath?

BUT I do agree 110 % with the above post about "stop drilling". It's essential in this case. Just choose any old drill of dia just a little more that the width of the crack. Choose a point that's "just ahead" of the crack then drill all though (but be careful, that GF looks pretty dirty so be sure to drill just AFTER the crack stops.

Ditto the 2nd hole (two holes are essential) but this time you place it just BEFORE the crack has started.
 
My gut feeling is the drain is the source of the problem because the glass fibre the pond is made of looks horribly thin from the photo, and with all due respect you quite likely initiated the cracks when you cut it. The further problem is that unless you have that drain connected to something whenever you use it a cavity will develop under that area of the pond and lead you back to the problem you now have.

As evrything is so thin I would get rid of that drain altogether - fibreglass over it totally and get a small pump for emptying. Another downside of the drain is that currently you know where it is but in 5 years?? And then you dig through that period of detritus in the pond bottom and the drain will block - guaranteed!
Rob

A good point. I managed to do one fibreglass coat today after applying the advice you’ve all given to me, I am concerned that even though I’m reinforcing the area around by the drain, it could still reappear. I’ll have more time on it tomorrow and will do two layers on both sides.

Thanks again everyone.

Arnold9801
 
I am a boatbuilder & used to do big GRP repairs for a living. First its a pond so it hasnt got to look marvelous. Grp doesnt have to be done from both sides it can be done from either side.
What you do need is to sand or grind the surface back to clean material preferably to a feather edge in the middle where the crack or hole is. I use fibre backed sanding discs on a grinder for this, its gotta be clean. A wipe over with acetone is not a bad idea but not essential if its been sanded back well. In weather like this you are on a hiding to nothing unless you can heat it, Infra red heat lamps are good for this, In fact i have done grp work when it was snowing using one! You should be using Chopped strand mat, for fixing a hole in a pond like that two or three layers of 450gm CSM will be more than adequate.
Do not exceed the max catalyst ratio it wont speed up the cure if its cold.
Cut your glass into patches the right size or on big runs have a stack of oblong pieces ready cut.
Applying the resin. You will hear much about Stippling the resin into the mat, Chopped strand mat has a binder in it which holds it together while the resin soaks in. Waste time stippling & it will fall to bits when you go to put it where its to go!
Nobody who uses glass for a living does this anymore. I use a wetting out board, bit of plywood, cardboard, take your CSM piece one at a time slap resin on it, turn it over & do it the other side. Put it where it is to go then do the next bit the same.
Trick to good fibreglassing is to get the air out & consolidate the laminate. For this you need a paddlewheel roller for size you need 1 1/2" to 2" long will be fine, when the wet glass is in place roll it down & the roller wil get the air out & hey presto you have done it!
 
Hi,

Lots of good advice given.

Personal safety is paramount in using fiber glass materials. Rubber gloves to protect hands and be aware there is a real fire risk; Acetone is highly flammable. Sanding dust isn't good for health either. Get it on your clothes and it won't come off.

Speed is important; don't mess around once the resin has been catalyzed because once it starts to set it can't be worked any longer; in hot weather set up time can be rapid. Don't try to fiberglass in cold conditions. Don't use metal items for mixing the resin and catalyst; we used wood.

We used to make all manner of items from gutters; bath panels; tanks and up to 16' roof sections for power stations; we used to cut the front out of a 5 gallon plastic container and fill it with resin then catalyze; I would use a 15" roller to add the resin and my workmate would consolidate using a washer type roller; on the big sections rollers were on long handles; we were on bonus and worked at a frantic speed; in summer when it was hot I've seen smoke coming from the glass fiber as it rapidly set; at the end of the shift I used to remove my boiler suit with wellies still attached and stand them by my locker; fiber glassing is a messy job and it's difficult to clean up. Two open containers were filled with acetone for cleaning equipment and one day there was a Whoosh as they ignited; we think it was the sun shining through the roof windows.

For things like shop fronts we used to lay up on a huge plate glass table; all moulds had to be treated with release agent; we started at 7:30 and worked like mad preparing moulds and gel coating then a short breaktime at 9:00; after break the gel coat was ready and we would then lay up till dinner time; after dinner it was gel coat then a short break and lay up again. Women did the light items like bath panels the guys the heavy items; a team made any repairs and a guy used an air diamond disk about 2" diameter to do the trimming. The items were released from the mould then the mould cleaned in readiness to be used again. Gel coat and resin arrived in 45 gallon drums. Pigment was added were needed in the gel coat.

This was way back in the early 70's and the company was "Hippo Glass Fiber Products" Horbury Bridge. We made good money and although the work was at such a speed it was nice to see the end result; I ended up with dermatitis on my fingers so regrettably had to leave. I used to smell of resin but it wasn't as bad as when I worked in a Nitro Benzene plant.

Just passing a bit of time because it's too cold and wet to play out. :D

Kind regards, Colin.
 
I am a boatbuilder & used to do big GRP repairs for a living. First its a pond so it hasnt got to look marvelous. Grp doesnt have to be done from both sides it can be done from either side.
What you do need is to sand or grind the surface back to clean material preferably to a feather edge in the middle where the crack or hole is. I use fibre backed sanding discs on a grinder for this, its gotta be clean. A wipe over with acetone is not a bad idea but not essential if its been sanded back well. In weather like this you are on a hiding to nothing unless you can heat it, Infra red heat lamps are good for this, In fact i have done grp work when it was snowing using one! You should be using Chopped strand mat, for fixing a hole in a pond like that two or three layers of 450gm CSM will be more than adequate.
Do not exceed the max catalyst ratio it wont speed up the cure if its cold.
Cut your glass into patches the right size or on big runs have a stack of oblong pieces ready cut.
Applying the resin. You will hear much about Stippling the resin into the mat, Chopped strand mat has a binder in it which holds it together while the resin soaks in. Waste time stippling & it will fall to bits when you go to put it where its to go!
Nobody who uses glass for a living does this anymore. I use a wetting out board, bit of plywood, cardboard, take your CSM piece one at a time slap resin on it, turn it over & do it the other side. Put it where it is to go then do the next bit the same.
Trick to good fibreglassing is to get the air out & consolidate the laminate. For this you need a paddlewheel roller for size you need 1 1/2" to 2" long will be fine, when the wet glass is in place roll it down & the roller wil get the air out & hey presto you have done it!

Have messaged you Keith.

Arnold 9801
 

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