Per Carb and spotted windows

[Dan Stapleton 14]

Well, after 11 yrs of PW and not one issue with windows I did my first deck restore and have miniscule white spots on a UV sliding glass door. They have been their for a week because the customer did'nt inform me until today. (Stain day)Windows were pre-wet and rinsed during and after. I'm sure it is from the Percarbonate as I KNOW their was no brightener/neutralizer anywhere near them. I've read a recent thread about brake cleaner being used but I don't want to go that route. Any suggestions based on experience? Was thinking white vineger? Any help will be appreciated.

On a side note, although I don't have anything to compare it to, the Woodrich was a breeze to work with. The color was a bit different then I expected but from what I understand it may change a bit as it cures. I've lost my Woodginity!

[Russell Cissell 65]

When you say UV sliding glass door, is there actually a film on the glass or is the glass tinted?

If it is a glass surface and it was a percarbonate cleaner, i wouldn't expect the glass to be etched. You should be able to remove it with lots of water. You can try all sorts of things but lots of water is the key if it's what I am thinking.

The overspray from cleaners can dry to form a scale deposit. In your case in very small spots. Once all the water evaporates they become very hard to emulsify. I have messed with all sorts of fancy surfactants to try to speed it up but in the end, water and scrubbing works as well as anything.

If you do use some solvent or vinegar, be sure not to leave a film on the surface, otherwise it will dry cloudy on you. Once you have emulsified the overspray rinse really well or use several fresh paper towels. In really bad cases, you can use a razor blade to remove the bulk before you wash it.

Welcome to the wood restoration game!

[Deck Guy 14]

Dan,

I know some here disagree, but a straight percarbonate cleaner does not need be neutralized in the first place, so no brightener was necessary although I would suspect oxalic as the cause of any spotting on the glass. I can't explain how any straight percarbonate cleaner would spot the glass. It basically leaves baking soda as its residue, as I understand it. Whose percarbonate did you use? Some percarbonates promoted here may have chems added to help them act as a mild stripper too.

[Dan Stapleton 14]

Thanks Russ, the homeowner has tried windex several times, I'm going back Thursday to put back the wrought iron furniture (yippee) I'll try a mild soap, scrubbing and lots of h20.

[Dan Stapleton 14]

It was a cheap, locally bought percarbonate. The deck was stripped, then neutralized. I hope it's not the oxalic on there, I was so careful. I stripped what I suspect was Thompsons acrylic, three times and there were a few spots left. I went back and hit those few spots with the Percarb just to see what would happen......nothing. I've read the debates and am aware of your stance on the percarb/neutralization. The customer realizes that I should have been informed of the problem sooner.

[PressurePros 249]

A much better choice would have been to use EFC-38. It is not a straight percarb but has some bite to aid in stripping duties. Thompson's is more of a wax than an acrylic but can still be a pain to remove if fresh. I don't mean to preach to you as I know this is not the purpose of your post. Just some information to make your life easier next tiem around. As always, the right tools for the job. Get in the habit of perfomring test spots before you bid.

If the spots cannot be removed via water and paper towels as Russell sugested first ascertain that you aren't dealing with self cleaning glass. When i encounter problems like this I use a microabrasive made for buffing glass. If you get into wood restoration seriously you will probably be picking up a 7" variable buffer. I use this to polish the glass and remove any dried chemicals.

[Dan Stapleton 14]

Ken, It was'nt fresh Thompsons. Three years.....he thinks. The difficulty in stripping led me to believe that it was a Thompsons acrylic. I used a Sodium Hydroxide based cleaner that I had on hand. Next strip will be done with HD80. The percarb was just testing on my part. And yes, I will spot test any future decks, for sure. No more bonehead maneuvers like skipping that step. Spots aside ( you practicly need a magnifying glass ) they are happy with the attention I've paid their deck and know a quality product was used. Thanks to you guys on this forum, they think I'm Joe Wood Expert.

[Deck Guy 14]

Dan,

You don't have necessarily be careful with the oxalic anyway. I shoot it on with the x-jet, then rinse down the windows and moulding right away. That doesn't seem to affect the oxalic action on the wood at all. Some folks here rinse the oxalic off the deck as well. Also, mild acids won't etch glass unless they are allowed to dry on it so don't waste too much time avoiding windows, just rinse afterwards.

[Littlefield 65]

4 o steel wool will remove spots.