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Inflation & Testing of a Repaired Tube
Following a repair, the MBT should be inflated and the pressure should be verified when the ambient air
temperature is between 65°F and 75°F (18°C and 24°C).
Pressurize the repaired tube to 4.4 psi (303 mbar).
Apply a soap and water solution to the entire repair area. Air leaks will show up as small bubbles.
Continue this test and monitor collar pressure for at least three hours.
Repair Troubleshooting
Having problems bonding a patch to your craft? Try the following:
Q: Why do the edges of a new patch keep popping up?
A: Warm patch. The patch needs to cool off completely before checking the edges with a putty knife. Remember:
heat activates the adhesive, and pressure bonds the adhesive together. If your patch is still warm, the adhesive is
still activated and WILL NOT BOND.
A: Adhesive is not re-activating correctly with heat. Try a light solvent wipe over suspect adhesive to reactivate
adhesive, then, once dry, try re-heating and bonding the patch.
A: Solvent not applied correctly. The adhesive may not be chemically bonded to the patch fabric or the area to be
patched. With a solvent, remove the suspect adhesive from the fabric by rubbing with a solvent-saturated cloth.
Thoroughly remove the adhesive and correctly clean the fabric with a solvent, then apply a new coat of adhesive
immediately. Allow to dry.
The two-fold purpose of the solvent is to clean foreign debris and oils from the surface of the urethane and to
open the pores in the fabric to receive the chemical bond of the adhesive.
A: Improper sanding of old fabric. Remove the patch (re-warm and gently remove) and remove all adhesive from
both surfaces with a solvent. Now, re-sand the old weathered fabric. You only want to scuff the urethane surface
to allow the solvent to prepare the underlying fresh urethane for adhesive application. Sanded surface should
have an even dull sheen without speckles or shiny spots. Repeat the process of cleaning with a solvent and apply
adhesive immediately. Allow to dry.
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