Sika Accelerator Ratios Please

[ffsfrank]

Hi

I have to fix two patio slabs back in place. Because I only have one day a week on which it can be done (patio is used by cafe downstairs shut on Monday) I have bought some Sika accelerator. The only thing is I can't make head nor tails of the usage ratios. I have 1:2:4 given in the technical informtion. Also it says 5 ltrs per 50 kg of cement but is that made up or dry weight? Help please

Thanks
Frank

 

[r896neo]

They are referring to dry cement weight. So if you make up a batch of mortar with 100kg of sand and 25kg of cement then you disregard the sand weight as the accelerator only has a reaction with the cement. Add some sbr in there as rapid hardeners can greatly reduce the bonding/stickiness of a mortar.

 

[ffsfrank]

Hi Thanks for the reply. At the risk of further revealing my own ignorance what is SBR?

Cheers
Frank

 

[r896neo]

Its basically pva but not water based so suitable for outdoor use. If you do use it be careful to mop up any spills immediately as it will stain paving semi-permenantly if left