Staining on sma - Staining

[neatcon]

Hi all I was locked out there for a while, I am just wondering do any of you have problems when laying Stone mastic asphalt with the water and dust from concrete paths/edging etc staining the finished product. I have tried everything to eliminate this power washing the roller covering the patches etc, I have it down to a minimum, its as if the water is boiling on the material and leaving like a rusty stain.

[tarmal & Co]

Yes I know what you mean about staining. I too keep my roller as clean as I can change my water in tank before laying. Hose the finished layer off. But the odd bit of staining seems to happen like a dust on top. I had one customer moan a little, I explained it will wear off I went back and checked a couple of months later it was gone. New Sma/bitmac seems to attract dirt. I too would like to know if any one has any ideas.

[Dave_L]

Roller stains on a hardstone SMA can sometimes be due to limestone filler dust used, it is quite prevalent from one particular quarry I use but they warn you of this.

Looks unsightly but given time, sunlight and use they soon disappear.

[neatcon]

Some of the stains are from water and will wash out if hosed immediately, it seems that the water is boiling on the SMA there is a product currently being used on a runway in Dublin airport that totally eliminates any staining, I will get the name of from the cube in my local quarry, only heard of this product recently.

[Dave_L]

No doubt a runway product will be very expensive!!

[neatcon]

I think it was €3000 per 1000ltr cube, not sure of the ratio to water but wil ask the questions and the ingredients might help out a few here.. I tried a plumbing product once that keeps the heating system clean, it did work but the complete driveway had a dull look about it when finished but no staining and that was SMA from a limestone plant.

[tarmal & Co]

Yeah the cemex plant I go to told me yesterday that they do add limestone dust as fillers to their sma out of there chimney air filter system to get rid of it.

[Dave_L]

I've found only using a pure hardstone SMA (no limestonne filler dust) is the only way to a completely clean surface.

[neatcon]

Bituslip is the product that was used in Dublin airport to prevent staining etc, it is a release agent for trucks but it was used on the rollers in the water to stop staining and to keep the surface clean.
https://www.google.ie/url?sa=....w35jkZA