Rendering advise

[dlacheson]

I am new to this trade as I'm still learning at college. I recently did a repair job on a friends outside render. I used a mix of 4 sand (rendering), 1 cement and 1 lime. I cleaned up the backround and dampened it down before I applied the material using two applications. When I went back to see the job three days later, I noticed that hairline cracks had appeared in the render. Can anyone tell me how this could have been caused or how it can be prevented. Thanks.

 

[flynnyman]

when you say two applications do you mean a scratch coat and top coat?

 

[bigsegs]

shoulda gone 6:1:1 that mix is too hard..
4:1 on its own would have done..
whats happened is its shrunk..