[AuRavelling79]

Got a new custy today and it looks like his lounge window suffers from stains due to rain water running off of the stone clad wall  (cotswold colour) above as there is no bellcast top or deflection plate above the window. It really catches the rain in south-westerly squalls too.

He has asked if I can do anything about it as it looks awful especially in the sun.

Any ideas please?

[ftp]

I've got some like that, Viakal might do it. I have a bottle of fancy Crystal 550 (or something like that) cost me nearly thirty quid. Works ok 'till the next time you call round and it's all come back again.  :

[cozy]

Malc, the Germans use Hydrochloric acid in a powder form. It's like ftp says though, it always comes back. Sometimes in a week or two, sometimes later. I've tried a few things but never got rid of it permanently.

Private custies here have been able to claim weather damage on it and had the glass replaced. Sorry can't be more help.

[Steve CM]

http://robinson-solutions.blogspot.com/2009/06/removing-mineral-deposits-winsol-way.html

crystal clear

faultless stuff

[ftp]

That's the stuff - wrecked two windows with it so far 
It leaves the glass Hydrophobic wherever you wipe it. I'm not impressed myself and rarely use it.

[TC1]

I was asked by a garden centre for a price today, their glass has really heavy calcium deposits(looks just like frosted glass)  from their irrigation system, I tested a small area with some viakal and it did come off to a degree but will take ages spray the whole lot and clean, so would be interested on hearing if their is a better de-scaler out there.

Tony

[Steve CM]

That's the stuff - wrecked two windows with it so far 
It leaves the glass Hydrophobic wherever you wipe it. I'm not impressed myself and rarely use it.

i've used it on countless windows with no problems. nothing else i've tried shifts it as good as this!

[TC1]

You bloody star, just watched their video and that stuff looks great, justb the job I hope!

Cheers Steve!

[mistersqueegee]

CC 550 is a hydrofluoric acid and can cause a problem called tin etch haze. In the States all glass is produced by floating the molten glass out of the oven on a layer of molten tin. As the glass cools some of the tin becomes embedded on that side of the glass. When CC 550 hits that side it reacts w/ the tin and causes a discoloration in the glass.
You also need to where chemical resistant gloves as the hydrofluoric acid can go thru your skin and actually start pulling minerals right out of your bones. They say the pain is excruciating.
You only need CC 550 if the deposits have silica in them. I would try oxalic acids of even hydrochloric acids.

[wizard]

If its that white haze you are talking about I us Dr. Power and get good results but takes a lot of elbow grease and I charge the earth.So time I come back for a second time a few weeks later.I am thinking of useing a random orbital sander with a felt or fibre pad and Dr Power on damp glass.