Hiya Dave,
You said that you had read where Jeff thought there might be a 'third' type of glass...I would agree with him, now and again you come across glass that just will not come right.
I've a couple like that myself, on the upstairs yo ujust do the best job you can, on the downstairs I still use WFP, but squeegee the glass, you don't have to worry about detailing and it works out to be only a quick going over with your squeegee.
I have also had windows where I have sprayed a solution of detergent (in my case Unger liquid) onto the brush head, cleaned a handful of windows in this manner and then gone back over them again, making sure they were washed and rinsed properly to get rid of any detergent residue.
If I still used my trolley, or had a backpack I would also try adding a couple of drops of GG3 to a 25l container of pure water.
I think I have read where Justin Ruggles has done this to good effect (my apologies to Justin if I have got that wrong by the way).
A couple of drops in the water shouldn't affect the TDS too much, but may well lower the surface tension of the water and therefore reduce beading.
With this glass, it is like there is a film of silicon over it, it beads up but as David has said, the beads are microscopic, and often follow precisely the line your bristles make on the glass, and you just know that some of those will dry spotty.
Another option is too use a hand sprayer filled with whatever deterent solution you use and spray you brush head and bristles prior to starting one of these accounts.
scrub the bristles of the brush between your fingers so that you give them a thorough clean, turn on your pump and rinse the detergent off the bristles.
Providing you aren't using washing up liquid in your water this only takes a minute or so to do.
It may well be that the bristles of the brush are picking up some of the sealant the glass was bedded into, or perhaps the rubber seal too.
If your neighbours house is one of these types that always dry spotty, ask if they would mind if you experimented on them.
You could then try such things as I suggested in this reply, one or the other might work.
On one account (my cricket club actually
) I had to go back over the windows because they just didn't look right, so I attached my soapy applicator to my pole and gave the windows a good soapy scrub.
It more than doubled the time taken to clean the windows, and it took ages to get them washed and rinsed clean with pure water, but the results were worth it.
This won't be the problem with your windows though as these hadn't been cleaned for a few years and there was a film on the glass that only a detergent would remove.
But you really need to find an account you can experiment on, the time it takes you will be well spent, as you will know in the future who best to tackle a job that dries out in this manner.
Ian
