Putty knives

[tonkski]

I replaced some of the putty on some window frames today. It went ok, with a bit of trial and error to trim the putty neatly. I used a putty knife similar to this one:

are putty knives mostly that particular shape, with one curved edge? How am I supposed to orient it when trimming off the excess? I couldn’t find many YouTube videos using that kind of knife rather than a simple filling knife, which seems just as good, if not better, for applying putty.

[Murmansk]

My limited experience of replacing broken bits of glass in windows leads me to feel that the putty knife is ideally shaped for the job although a filling knife is a good second but less good if the window frame or sill stops you holding it at the required angle which will inevitably be the case in certain places.

The tool is not used to apply the putty but to shape and finish it - the application of the putty is done by hand once a ball of putty has been kneaded and warmed to make it soft and sticky.

[Murmansk]

I remember seeing someone applying putty to a window frame on The Generation Game in about 1975 and they moved alongand applied it in a continuous length, pressing it in with their thumb every couple of cms

[charles]

Yes, having made a warm ball, you then make it into a long roll. This you then push into place.

[alan_m]

Used for removing putty as well as finishing it?

[Tricky Dicky]

As already mentioned putty is applied by hand and the knife is simply used to form and smooth the fillet. The angled straight edge is used to form the mitre like corner either working into or out of a corner.

[tonkski]

Thanks all.

[Brian Gaff]

Yes, I have a putty knife here that used to be my grandfathers, and although its basically the same shape with one curved and one straight side, it seems to be made of a springier material. I now have no windows in need of putty, on the outside anyway. The curved edge did make it smoother to my fingers. Putty really pongs though, or at least what I used did, and getting rid of the smell from your hands was very difficult. Brian

[Paul]

This is what we use for putty. I don't know why. My boss on my maintenance team, showed me how to do a window (for the rental houses we maintained).

And oh my God, the horror. why put pictures like this on web pages :-) That's not how you do it. it doesn't have to look that ghastly. The putty knife can fix that of course, but you'll have fun cleaning up the glass later without mucking up the putty.

Things are coming together here, in the "knead the putty rope" section. The purpose of your tool at that point, is to finish at a 45 degree angle so water will run off. A sealed bag of putty here, consists of a soft white material, plus the bag has a quantity of oil. When you knead the putty, some of that oil goes into the work, to make the rope pliable without being runny.

When putty sets and hardens, after enough years it shrinks a bit, and pulls away from the glass. Allowing materials to get between the putty and the glass. This is why, the next time the glass needs replacement, the putty comes out pretty easy.

At the hardware store, sometimes they look at you funny, when you ask for a "bag of triangles", the things for holding the glass in the frame. (There are a couple styles.) The Italian hardware store, the staff there knew what I wanted, and they had some. The big box stores were clueless. The Italian hardware store has everything. When I wanted a #7 wood screw, they had it.

And I can't remember the details now, but painting the frame before the putty step, may make a better surface for the putty. But then, it would lengthen the project time considerably.

It's been a long time, since my last window repair. All I do these days (to the wood frame windows), is paint'em.

Paul

[Robin]

glazing sprigs