Detailing Tool For Fake French Windows (Long Post)

I had a call today from a lady to give an estimate for a home that has apx. 40 fake French windows (12 over 12’s) or the kind with the plastic mullion bars over one single pane of glass. She said these mullions are fixed and will not come off of the window. I’ve already got another huge 5,000 square ft home with all true divided lites lined up to do in March so I’ve really been racking my brain trying to make life easier when it comes to doing French windows.

I’ll fan the huge home with true divided lites with a 6" squeegee then detail with a Huck towel. The smaller home with the fake mullions I’ll use a mix of distilled water and denatured alcohol or maybe even a commercial spray foam window cleaner, scrub with a micro fiber towel then buff dry with a huck towel.

Both of these methods are going to require a ton of detail work and getting all of those hundreds of little corners will be really rough on my fingers. So I came home from work today determined to find something that will make it much easier. I plundered through my utility room looking for something to make a detailing tool with then I suddenly thought about the 3" putty knife that I use to aid in taking screens off. I’ve got several French doors in my house with fake mullions so I started messing around with various methods.

I ended up just spraying foam cleaner on the small fake French panes then scrubbing with a micro. I then folded a huck towel in half and draped it over the blade of the small putty knife. I detailed the edges and corners with the corner of the putty knife (covered with the doubled over huck) as if it were a scraper. Then I found that I could actually buff the whole french pane (not just the corners and edges) with this new detailing tool. This method gets the corners, edges, and the whole pane itself cleaner (dryer) than any other method I’ve tried and with much greater ease. No more tearing my fingers up buffing and detailing these French panes. The huck towel seems to stay in place on the 3" putty knife best if you push forward in one direction only just like when using a metal scraper.

I don’t know that this will speed things up any but I’m pretty sure that it will be so much better as far as improved quality of detailing and my fingers won’t take such a beating. I think this is really going to work like a charm.

I’ll find out for sure in a couple of weeks. Just thought I’d share this with the group.

I’ll still be fanning true divided lites but I’ll use this new detailing tool with the huck towel to detail the edges and corners dry.

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Thanks for the tip – we all run across those.

Did you use a stiff or flexible metal or a plastic putty knife? What width?

It’s a metal 3" angled putty knife and it’s pretty stiff. Get a good quality one with a really good handle for comfort. This is the same 3 inch putty knife that Dan Fields suggest for cleaning residential window frames during post construction window cleaning. Turns out it’s useful for removing screens and now for detailing French windows. The corners are so clean and clear using this tool for detailing.

Actually the 3" angled putty knife does have some flex to it but overall it’s pretty stiff.

How have the knife’s edges treated the huck to date (rip, tear, shred?)

I think that will be the one drawback in that the corner of the putty knife blade will cause wear on the huck towels. But on most gigs there are only a small number of french panes.

On the gigs that have hundreds of french panes I’d rather put wear and tear on a .50 cent towel than on my fingers and hands. Of course on that large gig with 100’s of French panes we’re talking more than one huck towel.

Still though, for enhanced results, ease of work resulting in less fatigue, and less long term wear & tear on the fingers & joints I think this may be a good trade-off with extra wear on hucks. I can always buy a new box of hucks but once your finger joints are shot I’m not sure what can be done.

I still need to put this method to the field test but it worked very well on my fake French windows in my house.

Thanks for the tip. I’ll be doing mostly French window homes out here.

You’re quite welcome. Hopefully this will help save our fingers and those tight corners of all those french panes will be cleaner than ever.

If its good solid fake plastic frenchies & the bars aren’t coming away from the windows (i.e. trapping dirt) then this is the perfect job for wfp. The ones I generally come across are cheap & nasty & are pulling away hence the dirt gets trapped in the gaps & bleeds later.
I think most companys are stumped when it comes to these windows & getting the job done faster. Sörbo tried it with there multi-squeegee effort & I never saw that one take off.
I use the end of the squeegee wrapped in your choice of cloth for detailing these types.

Just to inject another thought. With any type of mullion they usually always cry like a baby,especially the plastic type and to make things even worse they usually either caulk in the screw holes to make removing a total PITA!

We have tried everything possible…on the exterior, pure water cleaning all the way a good scrub & thorough rinse usually always does the trick.

In the event you have to do them traditionally (interior or exterior)…what we’ve found effective is…a can of “Air” for blowing off PC keyboards. We tug lightly on them blow the air into the cross sections then squeegee & detail.

Starting at the top working our way down. Sometimes you can snap them slightly to dislodge water but…alot of times you get “snap back” onto previously cleaned glass.

As Richard describes, the majority of fixed mullions I see are glued (at least partially) to the glass.

Craig, That’s sounds like a great idea. I’ll have to pick up a can of that stuff and try it on my fake mullion windows at home. I’ll let you know how it works for me. It seems that you would not only have to blow the water from top to bottom but also from one side to another side away from the pane you just squeegeed. Is this correct? Thanks for this great tip.

Larry, I guess I need to clarify that these mullions are held onto the window by screws at the frame area. Unfortunately there is caulking or plaster over the screw heads so the mullions are fixed and can’t be removed without messing up the caulking (and paint). There is actually air between the mullions and the glass so it creates a big problem. The only way I’ve ever been able to clean these fake French panes is to saturate a towel with (distilled water/alcohol ) solution and scrub the pane while attempting to avoid getting the solution behind the mullions. I then quickly buff the glass with a dry cloth. This is a time consuming and laborious method but I don’t see a way around it unless that canned air stuff really works.

What i’ve found to be the most effective way is…prior to cleaning(if its going to be traditional) is lightly snap the mullion (after wetting) to release excess water… then starting at the top spray the air at all portions of the mullion both horizontally & vertically then clean each section moving down repeating the same procedure until you reach the bottom.

Although a bit more tedious…there’s always D.I./denatured alcohol mix 50/50 mix applied with 2 seperate micro-towels 1 to apply & 1 to buff.

had a question on this. So did you wet the whole pane with a sponge? and let it just drip down? I did a similar job today and it took twice the amount of time then i anticipated. every time i thought i had it done and went to the next window i went back only to be frustrated and realize that one of the pains had a run in it (when i say one of the panes, i mean one of the fake panes…because its all the same piece of glass. question, was i in the wrong to start on top and let the water just fall over the place?

With fake panes I just use less water and do side pulls so the majority of the drips go down the panes instead of through the divided area to the bottom panes

Exteriors I would just use a WFP and rinse wicked good

Mike Radzik

Pro Window Cleaning

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I’ve done the huck over putty knife in the past and it works extremely well

Mike Radzik

Pro Window Cleaning

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I’ve been cleaning windows for 28 years. Use this product with microfiber towel. Sprays on like windex but because it’s wax based it polishes perfectly clean in seconds.

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Where did you buy it? I can’t find it anywhere online or in the store.