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Getting Your Window Trim Studs And Glass Height Right!

posted Aug 13, 2017, 8:31 AM by Dane Belden   [ updated Nov 20, 2017, 6:56 PM ]
When people restore their fixed glass window channels, or replace factory glass with new glass questions arise regarding the proper placement of the window trim studs or the height of the sealant bed necessary for the trim to fit properly in the opening. We have put together a simple graphic and calculation based on what is known to determine these unknowns. Keep in mind that most trim was designed to be flush with the surrounding body panel (roof or quarter) and the trim is to be in contact with the glass. So knowing these facts as well as the trim height (“B” in our equation), glass thickness (“A” in our equation), window channel depth (“C” in our equation) and the standard GM A-Body trim clip geometry finding the stud height from the channel bottom and the thickness of the sealant bed are really just a simple math problem. Do keep in mind that being off a 1/32 of an inch isn’t a big problem – certainly GM had quite a bit of variability in their stud placement. As you might be aware, they did use a sealant system for their windows that incorporated a foam “dam” that kept their sealant from oozing into the passenger compartment on the window to be seen from the outside. This foam dam also effectively set the height of the sealant bed, so it is good practice to do the same when setting your glass. There are a variety of foam tapes available for just such a purpose. New glass is of a different thickness from factory glass (usually thinner) so take that into account if you are replacing your old glass with new.  Care to download this graphic?  It can be found on our "PDF Downloads" page by CLICKING HERE.  Scroll to the bottom and download it from the list today!