I'm trying to find a 'proper' glue that will 'weld' flexible PVC
sheeting and I'm not having much success. Just about all of the
advertised products that I can find do *not* truly weld the material and
it can be simply peeled apart at the join.

The best I have managed so far is PVC pipe welding glue, for example
Weld-On 725 Wet'R'Dry which certainly welds the material such that the
joint is as strong as the material but it de-plasticises it
considerably.

Is there any similar glue out there which will really weld the PVC but
not de-plasticise it too much?

Can any plastic gurus out there help? FWIW the 725 Wet'R'Dry contains
Tetrohydrofuran, Methyl Ethyl Ketone and Acetone.

--
Chris Green
·

On 18/06/13 16:26, wrote:
I'm trying to find a 'proper' glue that will 'weld' flexible PVC
sheeting and I'm not having much success. Just about all of the
advertised products that I can find do *not* truly weld the material and
it can be simply peeled apart at the join.

The best I have managed so far is PVC pipe welding glue, for example
Weld-On 725 Wet'R'Dry which certainly welds the material such that the
joint is as strong as the material but it de-plasticises it
considerably.

Is there any similar glue out there which will really weld the PVC but
not de-plasticise it too much?

Can any plastic gurus out there help? FWIW the 725 Wet'R'Dry contains
Tetrohydrofuran, Methyl Ethyl Ketone and Acetone.

MEK and acetone are enough to dissolve PVC and will weld it

The solvent CEMENTS also contain dissolved PVC to gap fill.

If by de-plasticise you mean loses flexibility, thatextraPVC is probably
the root cause. You want pure solvent brushed on then a rolled lap joint
alone.
The only gap filler that might work is 'original' evostik..and that may
or may not weld the plastic. If not, that too will peel off.

Similar stuff to solvent weld is in PVC repair kits.

Of course the best way is a pair of hot wheels to melt the plstic and
roll a hot seam well along the length.

If you can afford a few grand for teh kit..:-)





--
Ineptocracy

(in-ep-toc-ra-cy) €“ a system of government where the least capable to lead are elected by the least capable of producing, and where the members of society least likely to sustain themselves or succeed, are rewarded with goods and services paid for by the confiscated wealth of a diminishing number of producers.

"The Natural Philosopher" wrote in message
...
On 18/06/13 16:26, wrote:
I'm trying to find a 'proper' glue that will 'weld' flexible PVC
sheeting and I'm not having much success.


Of course the best way is a pair of hot wheels to melt the plstic and roll
a hot seam well along the length.

If you can afford a few grand for teh kit..:-)

Back in the early nineties i was YTS at a commercial garage, and it was my
job to be inside the curtain siders leaning on the board against the patch
that was being 'welded' on to close up the knife slits all curtain sider
trailers got when parked in certain laybys in the area,

The patch was cut from an old curtain taken off a wrecked trailer (just
thick pvc, always blue back then for some reason) so no heat activated glue
or owt (tho i believe the 'official' repair kits did have the heat activated
glued patches)
Anyway, they were heat welded using just a hot air gun and a steel roller
wheel, the roller was nothing special, just a wooden handle and metal wheel
with shallow ridges in it, but had to be pressed very hard against the
backing board to ensure a good joint, and the 'skill' was getting the
plastic to the right temp, which was not far below the point it began to
bubble then turn black and crispy.

But once repaired like this, the splits never came open again, naturally
that is, often we placed patches on patches on patches untill it became too
bulky and the curtain get jammed in the end winder when rolling it up.