Adding water to a sand and hydraulic lime mix

[michael]

As I understand it, additional water should not be added to a sand and cement mix to loosen it up once the mix has started to cure. Indeed the mix should be discarded and a new batch made up. Dose this rule also apply to sand and hydraulic lime mixes?

 

[chuckey]

As I understand it, hydraulic lime is really lime with added fine clays that set like cement. So adding water to a stiff mix due to time(where the clays are going off) would result efectively in an ordinary lime mix with a minute added amount of reacted clays. So it would loose the notional water proofness of hydraulic lime.
Frank

 

[Jon Maine]

We have knocked up hydraulic lime again the next day no problem, infact it has been fattier to use the next day. Just cover with a plastic bag or similar.

 

[Tom]

I've always made mine up the day before it's needed, knocking it back up and adding a little more water if necessary.

 

[michael]

OK, so its 2-1 in favour of adding water to a stiffening mix of hydraulic lime. If this were ‘Who wants to be a millionaire’ I don’t think I would be able to gamble on the correct answer with those odds.
I’m sure the partly cured mix knocks up again ok with additional water but as Chuckey points out are the properties of the original mix affected by doing this?

 

[chuckey]

From St Astier site :- http://www.stastier.com/guides/images/maknhlmb.gif "Re-tempering for up to 8 hours".
Frank