Adhesive & Foam repair

As touring techs and musition, we often need to patch up our road cases. The most frequent fix is to patch or replace the foam.

The first time I had to fix the foam in a case, I was simply told, “Glue the foam back in.” So, I grabbed the first glue I found—some good old-fashioned Elmers Glue—and slathered it between the foam and the case. Then, I squished it back together, and all I made was a big, mess. It took forever to dry, and it didn’t hold it together at all. So, I tried some super glue, and the only thing that stuck together was my fingers… It was a no-go!

Someone suggested Hot Glue, and that worked for the most part. It wasn’t perfect, but it held it together well enough to get through the tour. The biggest problem was that you can only put a thin bead of glue down, so I put down some stripes of glue and a bead along the edge of the foam, but it was still loose where I didn’t have glue.

The next time I was asked to fix a case, I knew what not todo, but the PM suggested 3M’s Super 77 Spray Adhesive. So, I sprayed some glue between the case and the foam and pushed it together, hoping it would stick. It didn’t really work, and I didn’t know what to do. The tour LD looked at me and said, “Did you let that dry first?” I responded, “Aaaaa, that’s what I’m doing!” Then he explained to me, with all the patience of a man who had been touring longer than I’ve been alive, that it works like Contact Cement and you can’t put it together until the glue is almost completely dry.

This took me down a path of figuring out how glue works and what works best for what application.

• PVA (Wood Glue/White Glue): Works by seeping into porous surfaces (wood, paper) and forming a strong bond as the water evaporates. Type II is versatile for indoor/outdoor use, while PVA offers a long curing time (up to 24 hours) for adjustments.
• Super Glue (Cyanoacrylate/CA Glue): It bonds instantly in seconds by reacting with moisture in the air. It’s best for non-porous materials and small, quick repairs.
• Epoxy (Two-Part): It’s made of a resin and hardener that create a massive chemical reaction, resulting in a very strong, rigid, and waterproof bond. Ideal for high-stress repairs.
• Polyurethane Glue (e.g., Gorilla Glue): This versatile glue needs moisture to activate. It expands while curing, filling gaps, and adhering to almost any surface, including damp wood, stone, metal, and plastic.
• Hot Glue (Glue Gun): This thermoplastic adhesive melts when heated and sets quickly at room temperature as it cools.
• Contact Cement: It’s used for projects that require immediate adhesion, like laminates and veneers, where both surfaces are coated, allowed to dry, and then bonded on contact.
• It needs to dry almost completely for the glue to bond to the surface. Allowing the glues solvents to dry so that when it comes in contact to another surface with Glue on it it will immediately bond. These solvents have a hard time drying when not exposed directly to the air.

Spray on Contact Cement is the really the best way to Build and Fix foam in road cases. Case company’s use high strength Spray on Contact Cement. Your able to get great coverage of glue on the case and foam surface. This will claw every part of the foam is stuck to the case surface. There are several off the shelf products that work great 3M has several different blends that are suitable. Supper 77 is probably the most common, but the 3M Foam Fast 74 is also a great option

If you need custom foam for your road case or if you need foam Repaired email us at info@OCD-Labs.com