Sharp sand for mortar?

geographica

Have half tonne of sharp sand left over from rendering. Possible to use it for mortar for block laying (not a house or the likes, just a wall in a shed)?

Mr321

Yes it'll be fine

10-10-20

Should be fine but sift a bit of it to see what the maximum particle size is, just in case there are any small stones.

The Continental Op

The only issue is that it doesn't flow like builders sand so you have less movement when you push down on a brick/block. Makes a stronger mortar.

standardg60

Drop of washing up liquid in the water used to mix it will flow lovely.

monseiur

Mix it with lime at a rate of 3 : 1 Leave for a day of two to 'sour' then add cement for a top quality mortar.

10-10-20

https://www.boards.ie/discussion/comment/122634845#Comment_122634845

Is that the secret recipe for the creamy stuff that you see being used on YouTube? It's like whipped cream that some of them have, seem to be full of entrapped air, but none of my efforts have resulted in anything similar.

So you rehydrate the slaked lime in the sand with some water for two days, is that it?

monseiur

https://www.boards.ie/discussion/comment/122634886#Comment_122634886

Not a builder so never used it myself, but my uncle who was a bricklayer in the UK all his working life swore by it. I worked with him for a week while visiting (was just 17 at the time)

He'd mix it (in the mixer not by hand) at a rate of 3 sand to 1 lime add some water - the mix would be whitish grey colour . He'd make 4 or 5 mixes at a time and leave in one pile covered with a wet canvas sheet/tarpaulin to 'sour' as he called. It would harden slightly but was easily shoveled back into the mixer to add cement, water and sometimes dye. The mortar it made was sticky almost gooey and easy to work with. No plasticiser, fairy liquid etc. was required.

standardg60

Uk red sand when it came in courtesy of b&q I found nigh on impossible to work with without the addition of any amount of additives.

The sand here is a lot softer, did you guys find the same?

The Continental Op

https://www.boards.ie/discussion/comment/122638280#Comment_122638280

I really can't lay bricks anyway but I find Irish sand way to gritty even the stuff that isn't sharp sand. UK sand is great for bricks and you can make it nice and plastic.

10-10-20

I've heard it said, but I think in reality it just depends on the source of the sand at the quarry. Must be an ice-age/glacier thing.

Esel

Is it true that beach sand is no good for mortar/cement because it is too rounded?

The Continental Op

https://www.boards.ie/discussion/comment/122638557#Comment_122638557

Salt is why you don't use beach sand. I've seen it used in concrete in old houses and it makes very poor concrete.

Depends where the sand comes from yellow beach sand apart from the salt is fine for cement but some of the greyer courser sands can have round particles.

Not seen it here but in the UK you can also get river bed sand which is quite sharp.

10-10-20

https://www.boards.ie/discussion/comment/122638557#Comment_122638557

Correct, it's like custard in the way that it runs when you move the block, and it falls out of the joint as it has no ability to hold shape. But worse of all is the amount of salt within it.

geographica

https://www.boards.ie/discussion/comment/122627780#Comment_122627780

Using feb mix