Mortar question

[Tscarborough]

Re: Mortar question

If there is too little sand (or improperly graded sand), then the aggregate is unable to contain the shrinkage cracks of the paste.

[brickie in oz]

Re: Mortar question

Australian Standards for brickwork AS3700 actually allow for detergent in mortar in small quantities as it does for plastisizer, which after all is just an aerator like detergent.

An old friend of mine once told me that he did a degree in concrete engineering, and detergent was brought up.
Detergent is apparently a non corrosive and protects the metal and stops it from rusting, judging from the shine inside my mixer which never goes rusty, I'd say he way right.

[Tscarborough]

Re: Mortar question

There are two methods for specifying mortar, here or anywhere:
Proportional method (As shown above).
Properties method. This relies on laboratory testing of field ingredients to achieve a required strength, and the mix design is determined from that. Anything can be used for this, soap, dung, whatever, it will be tested to confirm adherence to required properties.

All of this is neither here nor there in respect to an individual working on their own home, they can do whatever they want.

Let me tell you where I come from and why I present the information in the way I do. I belong to around 6 DIY construction boards, and offer advice on masonry. I could offer the easiest way, or ways that "will work", but chose to always present the information as it has been developed by the professional organizations whose job it is to determine standards and best practices.

Sometimes this is overkill or different from local custom, but the important fact is that if followed it will ALWAYS work, and it has the advantage of being robust enough to allow for DIY error.

[jota112233]

Re: Mortar question

Terry.

I don't think I've ever mixed cement without using a splash of fairy (soap) in it.

It's a Welsh thing....

Enough said.

Jon