Rapairing part collapsed stone wall... Mortar?

[Siderealxxx]

Hi, new to this so... we have a retaining stone wall holding up part of the neighbours garden. A small section has fallen down and whilst it is bulging a bit in that area, I think a controlled removal and re-build in that small section (4' width x 2' depth) will hold it for a while.

Because we don't have any money we need to do this ourselves! I'm willing to learn but looking on the internet for advice is proving fairly fruitless. Essentially I'm trying to establish what mortar to use and how to mix.

It seems cement based isn't the way to go, so am I right in saying it should be 1 part lime to 3 parts sharp sand? Should the lime be hydraulic or non-hydraulic? How much water should I use in the mix? And how should I mix this... Anything I should buy? Any links/tips for laying techniques?

I know this is a specialist area but we've really not got the budget to get anyone in and I don't think it's too severe. Appreciate any help/advice!

Thanks, sid

 

[Himaginn]

Hydraulic lime, a 2.0 or a 3.5 depending on exposure and hardness of stone. I'd guess a 2.0 will suffice.
Here's an excellent link with plenty of answers:
http://www.limestuff.co.uk/pages/user-guides/how-to-mix-hydraulic-lime.html

 

[stuart45]

Apart from mixing for 20 mins, let it stand for 20mins to fatten up, then mix again for a couple more. 3.5 is the norm for exterior walls, although it depends what the original mortar is.

 

[Siderealxxx]

Thank you both so much. This is exactly what I needed to know. Best.