Michael Mcneil wrote in message
Another problem is using fairy liquid or similar in the mix. Use no
detergent. It will be stronger if you use no Feb or similar too neither.
Harder to work though.
I believe the *correct* amount of detergent actually makes a stronger mix.
Proprietary plasticisers, however, are not true detergents but very small
particle size salts.
IMO pva simply takes the guesswork out of the equation. How porous is the
surface, how wet does it need to be etc.