Joined: July 2004
||Posted: 08 Oct. 2019,13:07
If you send the images to me (use "newchurch three two" but as a single phrase [no gaps] with digits rather than spelling out the numbers, then AT gmail dot com), I'll post them to this thread for you.
Without the photies, we're working blind but, generally speaking, you will get nowhere with London Stone as the problems arose after installation, and is a known issue when these polymeric mortars are not correctly applied. And that will be Azpect's fully-justifiable defence: it was the installation that failed, not the product.
So, the next thing is to determine whether the stain is arising from the stone itself (usually rust or iron minerals), whether it's the doping oil used with the polymeric jointing, whether it's a stain from the actual resin binder, or whether it's a combination of these factors.
The doping oil stains do, eventually, weather out, but the tome required depends on just what oil has been used. There were some changes over the last 12-18 months with manufacturers shifting to cheaper, often vegetable-based, oils and these seem to be more prone to hanging around long beyond their initial welcome.
Rust or iron minerals can sometimes be shfited by off-the-shelf rust removers - see umpteen similar threads in this forum.
Resin stains can be more problematic, but there are products out there (such as Resin-Ex) that can sometimes help.
Send me the photies and we'll take a look.....
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