Someone recently gave me a small pre-formed pond, but it has three 1-2
inch cracks. I was wondering what the best way to patch them would be.
Perhaps a bicycle tire patch, or silicone? Thanks.

Contrary to what some will claim, there is NO adhesive that is
considered suitable to use with the type plastics the preforms are
made out of. You can slather on silicone, put liner patches on them
and a heap of other things.......but its certainly nothing I would
ever, ever trust. Best bet is use a hot air plastics welder and do the
repair right. You can cut small slivers off the preforms lip for
filler material and melt it into the cracks.....I have fixed many
preforms I find that way, and last year welded 6 preforms together,
that Walmart had cut in half so they cold not be salvaged when they
threw them in the dumpster......and not a one of them has
leaked.........

If you go with the silicone or polyurethane sealant, you still need to
scab a patch on top of it and use sealnat between patch and preform.
It also needs some form of mechanical fastener as well as it is very
capable of peeling up and coming off, as nothing sticks properly to
the PP or PE type materials.......You can use stainless steel pop
rivets, small stainless sheet metal screws, or stainless
stovebolts.......I fyuou use pop type rivets make sure to get sealant
in the stem hole and over the head or it will seep.


On 25 Jul 2005 11:45:35 -0700, "john"
wrote:

===Someone recently gave me a small pre-formed pond, but it has three 1-2
===inch cracks. I was wondering what the best way to patch them would be.
===Perhaps a bicycle tire patch, or silicone? Thanks.


==============================================
Put some color in your cheeks...garden naked!
"The original frugal ponder"
~~~~ }((((o ~~~~~~ }{{{{o ~~~~~~~ }(((((o

Contrary to what some will claim, there is NO adhesive that is
considered suitable to use with the type plastics the preforms are
made out of. You can slather on silicone, put liner patches on them
and a heap of other things.......but its certainly nothing I would
ever, ever trust. Best bet is use a hot air plastics welder and do the
repair right.

Polyethelyene? Or something else? Anyway, yup, totally right. Some
kinds of plastics simply cannot be glued reliably. I got my plastic
welder from Ebay, $50 chinese job. Works okay for small jobs. Need
a compressor of course.

C//

First, determine what the "plastic" is !

Chances are, it's fibre-glass - that's a thermoset, and the only way to
repair is to use a fibreglass repair kit - relatively cheap at any motorist
outlet. Do ensure the glass fibre is FULLY covered with the resin, no loose
strands or ends, else you'll get leakage by "wicking" - water seeping out
through the strands of fibreglass.

(You may be able to see whether it's fibreglass - look at the cracks, is
there a white substrate with evidence of "fibre" - that's fibreglass with a
paint job).

Plastic welding will only work on thermoplastics. (difference between
"thermoset" and "thermoplastic" - once set/formed, thermoset cannot be
re-formed by heat - thermoplastic under heat will becomple soft and pliable,
and thus can be welded).
BUT - successful welds need same-type plastic welding rod, so PVC rods will
not work (seal) polythene or polyurethane ponds (and vice-versa), for
example - and there's more than 3 thermoplastics!

If in doubt - google or contact the pond mfr (who should advise not only the
plastic it's made from, but also the repair technique)

Hope this helps

"john" wrote in message
oups.com...
Someone recently gave me a small pre-formed pond, but it has three 1-2
inch cracks. I was wondering what the best way to patch them would be.
Perhaps a bicycle tire patch, or silicone? Thanks.

I seriously doubt its fiberglass in a preform......Yes, they are
available but few and far between......the general preforms are
usually always a PP or PE material.....



On Tue, 26 Jul 2005 18:17:05 GMT, "Yabbadoo" wrote:

===First, determine what the "plastic" is !
===
===Chances are, it's fibre-glass - that's a thermoset, and the only way to
===repair is to use a fibreglass repair kit - relatively cheap at any motorist
===outlet. Do ensure the glass fibre is FULLY covered with the resin, no loose
===strands or ends, else you'll get leakage by "wicking" - water seeping out
===through the strands of fibreglass.
===
===(You may be able to see whether it's fibreglass - look at the cracks, is
===there a white substrate with evidence of "fibre" - that's fibreglass with a
===paint job).
===
===Plastic welding will only work on thermoplastics. (difference between
==="thermoset" and "thermoplastic" - once set/formed, thermoset cannot be
===re-formed by heat - thermoplastic under heat will becomple soft and pliable,
===and thus can be welded).
===BUT - successful welds need same-type plastic welding rod, so PVC rods will
===not work (seal) polythene or polyurethane ponds (and vice-versa), for
===example - and there's more than 3 thermoplastics!
===
===If in doubt - google or contact the pond mfr (who should advise not only the
===plastic it's made from, but also the repair technique)
===
===Hope this helps
===
==="john" wrote in message
oglegroups.com...
=== Someone recently gave me a small pre-formed pond, but it has three 1-2
=== inch cracks. I was wondering what the best way to patch them would be.
=== Perhaps a bicycle tire patch, or silicone? Thanks.
===
===


==============================================
Put some color in your cheeks...garden naked!
"The original frugal ponder"
~~~~ }((((o ~~~~~~ }{{{{o ~~~~~~~ }(((((o