The Importance of Glass Prepping and Priming

On this the first post for 2014, I would like to thank everyone for reading and commenting on my posts, without you this blog would be nothing. I would also like to thank Deb Levy and her wonderful staff for putting up with me these past months and for the opportunity to share my thoughts and opinions without restrictions.

The New Year will bring many new vehicle designs, technologies and challenges that we will tackle together. Feel free to call or email me with your questions, concerns or revelations that can be shared with all. This next year will be fun. May you all have a happy and prosperous New Year!

The next step in glass preparation is prepping or priming. There are primerless urethanes and they work very well as long as the glass is cleaned properly. However, if not cleaned properly, the installation could be compromised. Most adhesives require the application of a prep or a primer to promote maximum adhesion. A prep is a secondary cleaner or application to prepare for adhesion. A primer is a chemical applied to a substrate to enhance the bonding. Whether a prep or a primer is required to be applied, it must be applied correctly. Some are applied and allowed to flash. Some are applied and wiped off, while some are applied twice. But all must be applied in one direction and not applied back and forth.

There is also a reason that some adhesive manufacturers offer “one-use” disposable applicators. They want the material to be applied with as little contamination as possible. There are some techs that use and reuse applicators to save installation cost. Though this may sound like a good idea, it is not. Introducing contaminants to the bottle of material will only cause the whole bottle to be contaminated. Dip once, apply and throw away.

The last thing I want to leave you with concerning glass preparation is when should you prep the glass? The following is my opinion and recommendation. It is not written in any instruction manual. I prefer to prep my glass before I take the vehicle apart. This allows me to inspect the glass for defects; check the glass to make sure it is the proper part for the vehicle; and let the primer/preps dry thoroughly. I then flip the glass over on my cradle to keep airborne contaminants from falling on the bonding surface. On cold days, I may even prep the glass in the shop before doing the mobiles. This allows for preparation in a controlled environment and allows primers/preps to dry thoroughly but this means you bought the glass, so make sure the glass is right.

In summary, if there is one thing you pay attention to and make sure is done right, it is to wash and prep the glass according to the instructions you are given. Nothing is more important to a successful and safe installation than a properly prepped glass surface.