[carl_foster]

 

[Justin Ruggles]

If you lean the bush against a brick wall small sandy particals can attach to the brush and then scracth the glass.

If you dont lean brush against it or on the floor then No.

Justin

[carl_foster]

thanks mate i must start washing the brush out more

[stephen d]

big article in professional window cleaning magazine on scratched glass(dec 2005 issue 5) worth reading

[Ian_Giles]

I would say that there is no chance whatsoever of WFP scratching the glass, any grit you may pick up by carelessly leaning your bristles on the ground or against brickwork will quickly be flushed away, the bristles of the brush simply cannot exert enough pressure on the glass whilst keeping the grit or aggregate in constant contact with the glass.
However, you can damage and sratch the frames with the brush head itrself (but not the bristles) you are likely to chip paintwork if you are not careful, but scratched glass? No chance.
You are more likely to scratch the glass with trad methods, and even then not with the squeegee.
It may be possible to mark the glass if grit or sand is embedded in the applicator, but you'd have to work bloody hard to be able to do it!

You may also scratch glass if you have to use a razor scraper on an initial clean and have to get off lots of sand and cement, but in 22 years of window cleaning I have never known it happen.
Even if it did, you would know by the feel of the applicator instantly, you'd have to be one clumsy sod to do enough damage for it to be actually noticable.

The trade most likely to be guilty of scratching the glass is the Painters and Decorators, and I speak from real experience.
Prior to being a window cleaner I was a decorator for 10 years, and I do know what I am talking about.
When the decorator is prepping window frames, his sand paper will often come into contact with the glass, it is very hard for it not to happen, the lightest of touches will scratch the glass.

But WFP scratching the glass? No chance!
I was going around one of the shows prior to buying my WFP, on one of the stands the rep was making a big deal about the fact that their jets were non metalic, and that unlike metal jets that protruded from the body of the brush, would not scratch the glass.
It seemed to make sense...until I actually had a brush with metal jets that protruded from the body of the brush that is!
To be able to make the actual jets come in contact with the glass I'd have to put so much pressure on the glass I'd probably put the window in!!!

So even the metal jets won't scratch the glass.

What about iced up bristles then?

Do behave! you won't scratch something as hard as glass with frozen water! It won't happen! so if you are worrying about it in these freezing cold times...DON'T!

Regards,

Ian

[jon adams]

re scratching glass with trad methods,  this happens very rarely but is easily done ex: cleaning a kitchen window once there was small amount of sand from playpit on glass and ledge, put applicator on in up and down movement and straight away heard scratch from sand ooops  . scratch was visible and lovely  customer complained    but luckily didnt lose job 

[Ian_Giles]

The point being Jon, you knew the moment you had made it!
You don't just hear it, you can almost sense it through your fingers through the applicator.
You might, very, very rarely cause a scratch with an applicator, and I honestll cannot think of an occasion when I have made a noticable scratch in 22 years.
The chances of it happening with WFP are even more remote (damage to frames from brush head notwithstanding )

Ian

[steve k]

Last month cleaned a small estate of detached - all with leaded windows and all with WFP -
I then moved on to another run when I got a call on mobile from a customer on first estate:

"you have got a problem...a big problem" he said

"have I? What`s that then?"

"your pole has scratched every window in my house, you must have got grit in the brush"

I had thoughts here of a massive insurance claim and then remembered that the insurers do not pay out for damage caused to the glass being worked on so was really worried.
Got round to the customers house and asked him to show me the damage.
Every window had 1/2 inch of scratching right round the joint between frame and glass...ON THE INSIDE!!...

What a relief to tell him and show him with the use of his fingernails that the scratches were on the inside and almost certainly the result of sandpaper from whoever had prepared the frames for painting.

He was really apologetic but I was just so pleased that it was not me.

[Justin Ruggles]

Sorry Ian I disagree, If you have a slow flow rate then the chances of the grit being removed quickly are pretty slim. The chances of the flowing water removing anthing on the outter edge with a slow flow rate slim as well or it might take a min or 2 for the water to remove that.

Just to prove my point about this, get a bucket of pure water and make sure there is nothing but pure water in there. Now place the brush on to a wall and then placew into the bucket. Look and see whats in there.

Now do the same again, but before you place the brush into the water, turn on for say 40 sec (approx time to clean one window) now place the brush head again into the water. Your see there is still particals there.

Thou the chances of this making a visable scratch is pretty low, it can still happen. I vote No.

Justin

[Ian_Giles]

Justin, I do take your point, and I personally never leave to brush resting bristle first on anything. and even with particles left in the brush there is no chance of the glass being scratched!
It may theoretically be possible, but in practice it would be next to impossible.

with trad work the applicator can often get grit embedded in the sleeve, this grit is held in place, the pressure exerted by the window cleaner on the window is always going to be greater than that of the bristles of a brush, because of course the bristles will bend and give, you may not flush out the particles in the brush, but you simply won't be able to put enough pressure on the brush or hold a tiny particle of grit in place long enough to damage the glass.

I might even put my money where my mouth is and actually try and scratch one of my own windows by dipping my brush in sand

I'll have to make sure the missus isn't about though

I might even have a go at it this afternoon


Ian