Repair Your Therm-A-Rest - Outdoors Magic

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Repair Your Therm-A-Rest

Pushed for time? Click here
Therm-a-Rests are great until they puncture and make like a flat
tyre, but relax, it’s not the end of the world. Here’s how to fix
your self-inflating mattress using: a Therm-a-Rest Repair kit
(£4.00), a bath-full of water, a stove and pan, a plastic bag
and a jar of pickled gerkhins.

The materials in the repair kit are, say Cascade Designs, the manufacturers, the same as those used in their own workshops for the repair of stricken mats.


Slow punctures are generally apparent when the mat deflates slowly
overnight usually means a pin-hole puncture. Hard to find, easy to
fix. Some leak significantly only when part of the mattress is bent

Ctastrophic deflation, which happens more quickly generally
indicates a larger tear. Easier to spot, more extensive repair.

Location, Location, Location Use
water to find the leak. Inflate the mattress then either
submerse it and watch for bubbles or smear soapy water
across the surface to find the leak.Often the leak will
whistle softly under pressure. Once you’ve found it, mark is
with a pen or you’re bound to forget exactly where it
Boil The Adhesive To activate the
adhesive you need to boil it for 3 minutes. The old tubes
always congealed after first use, but the latest sachets
mean you can make at least three repairs with each kit,
though they’re not reusable.
Stick It Make sure the surface of
the mattress is dry, though they can be repaired in wet
conditions and open the valve to prevent damage. With a
pin-prick type repair, it’s simply a question of rubbing
some adhesive into the area of the puncture using the wooden
‘lolly stick’ supplied.
Patch It: For bigger tears, like
this one which was previously covered with an acre of duct
tape and a Compeed blister plaster, spread adhesive over the
area – you have a couple of minutes before it
Then stick one of the pre-cut patches
over the area.
Before covering with a handy plastic bag
then plonking the hot pan down over the patch to heat the
adhesive and seal the bond. The placcy bag is to prevent the
adhesive from stickign to the bottom of the pan. A logical
move since sleeping on pans is woefully uncomfortable. Make
sure the valve is open to prevent serious side effects as
the air inside the mattress expands.
Finally remove pan and bag, before seeking out a
jar of pickled gherkins and rolling it over the patche and repaired area in a
stylee. This ensures that the patch is firmly in place.
Et voila. Simply leave the repair
to stabilise for 10 minutes before use and be more careful
next time.

In the past I’ve used a Compeed blister
dressing overlaid with layers of duct tape which actually
worked okay for about a year (carry duck tape rolled around
a 35mm film cannister for ease of use). Duct tape will do
the job on its own, but it can be hit and miss, it also
tends to strip off if it gets very wet.

Seamgrip, the American seam-seal come
urethane adhesive thing works pretty well, but needs to cure
overnight, which isn’t always practical.

The best solution really is the genuine
Therm-a-Rest repair kit at £4.00


Carry the rest inside your pack rather
than strapped on the outside and exercise care with spikey
things like crampons, cutlery and roses. If you’re bivvying,
be doubly careful, certain spiked grasses and rocks can make
your mattress look like a pin cusion in seconds. Never lend
your mattress to anyone with long, sharp toe

Pushed for
If your Therm-a-Rest punctures, all is not lost. Make sure you have a four
quid Therm-a-Rest repair kit along for the ride and follow the
instructions carefully. You could also use duct tape in extremis

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