Bob Taylor is right about masking pouches with adhesive paper dots
[060211 MMDigest], if conventional sealants are used. But the beauty
of Hydrophane is that it doesn't make a laminar surface coating on the
pouch, which often stiffens it, but completely permeates the leather,
swelling and lubricating the fibres and making it airtight and supple.
This, though, makes masking ineffective. It's better to stick lifters
on before treating the pouches.
Fortunately, any surface Hydrophane residue at the centre spot where
lifters are to be refitted can be easily wiped away with a dab of
simple solvent on a cloth-covered finger, immediately after which hot
glue will stick perfectly. When fully set it's wise to apply a final
dose of Hydrophane.
Later, especially where no lifter discs are fitted, it's a good idea
to dust dollies and pouches lightly with real talc to reduce friction:
unlike French chalk, real talc will draw virtually no Hydrophane out
of the leather once it has soaked in.
Wivenhoe, Essex, UK