Know-How Notes: JB Weld Windshield Repair Kit Guide

Cruising along the highway, you are stuck behind a cement truck. Practicing safe driving, you have allowed two full car lengths between you and the truck. Suddenly, the tranquil serenity inside your car is shattered as a small stone gets kicked up by the truck and dings your windshield. Sometime these are glancing blows that sound worse than they are, but this time, it was a direct hit, and now you have a 1/4-inch bullseye in your windshield. “Well, there goes $300” you think to yourself as the reality of a replacing the damaged glass or a costly professional windshield repair.

It does not have to be that way however, as JB Weld Windshield Saver windshield repair kit promises to repair stars, combos, half-moons and bullseyes in windshields up to 1-1/4” in diameter. Using a special sun-activated clear resin, this windshield repair kit draws the resin into the glass so it sets quickly and easily, stopping the spread of the break and recovering your vision.

Prep and Cleaning

The key to this product is getting to the windshield repair quickly. The longer the car sits with a break, the more likely the crack will spread and get other contaminants inside the break, affecting the ability for thew windshield repair to work.

Inside the kit you get a pedestal tool, syringe with locking plunger, pedestal adhesive, resin, curing strip, pushpin, alcohol wipe, and a razor blade, everything you need to complete the task. You can use some black electrical tape to protect the resin from curing too fast during the process. More on that later.

The process starts be removing any loose glass. The pushpin helps work any loose glass out.

Wipe the area to be repaired with the alcohol wipe and let dry. Place a towel at the base of the windshield to catch any loose resin just in case.

Starting The Windshield Repair

Place the adhesive disc on the glass around the windshield repair, and make sure there are no air bubbles caught under it.

Next, attach the pedestal to the freshly applied adhesive disc. Press firmly to adhere the pedestal. If you choose, you can cover the area under the pedestal with black electrical tape to block the sun from curing the resin too fast. During our test of the kit, we cracked the glass at the chip by pressing too hard. It doesn’t take much to crack safety glass when it is chipped, so be careful. Luckily (I guess you can call it luck) the car had several chips, so we could finish the test. 

Open the resin tube. Do this away from the vehicle, as the resin will damage the paint if it touches it. Cut 1/8” off the tip of the tube, and carefully stick the tube into the pedestal and squeeze. Remove the tube and wipe away any excess resin. Replace the cap to save the rest of the resin.

Make sure the syringe is fully closed (plunger all the way down), and twist the tip into the pedestal. The fit needs to be very tight.

Using both hands, one holding the syringe, the other on the plunger, pull the plunger all the way up to the lowest detent on the plunger (the plunger will be fully pulled back). The spring clip will lock the plunger at this position. Let it rest for 10 minutes. The vacuum created by this plunger draws the resin into the break. Remove the tape from the back side of the windshield if you used it.

After 10 minutes, remove the syringe, allowing air to enter the pedestal, keeping the plunger in the full locked position. Then reinstall it to the pedestal. Push the plunger down to the second detent as shown, and lock it in with the clip. Let the assembly rest for 20 minutes.

Carefully remove the syringe and use the razor to remove the pedestal. This is done by sliding the razor along the glass under the pedestal. Wipe off any remaining resin from the glass.

Finishing Up

Use the remaining resin to finish the windshield repair. Squeeze the resin on to the repair and cover it with the curing strip. Smooth out any air bubbles in the curing strip. Remove the tape from the back side of the windshield if you used it.

Move the vehicle to a sunny area and let the resin sit for at least 15 minutes. The resin cures naturally in sunlight. If the sky is overcast, it will need at least one hour.

Once the repair has cured, remove the curing strip and use the razor blade to carefully clean up any excess resin on the glass should it be uneven. Clean the glass with alcohol.

The repair will be diminished but not completely gone. The main benefit of this repair is to keep your windshield from cracking any further. This is a relatively safe repair, just take some care when working with the razor and resin, and be patient.

Check out all the chemical products available on NAPA Online or trust one of our 17,000 NAPA AutoCare locations for routine maintenance and repairs. For more information on JB Weld windshield repair, chat with a knowledgeable expert at your local NAPA AUTO PARTS store.