You might wanna back off on the hardener a tad to give yourself more time. Also, smaller batches harden a little slower because the heat generated by the chemical reaction acts as a catalyst and smaller batches make less heat.
If you're using foam brushes you're screwed reusing them cuz the solvents that the other guys mentioned will eat them. See if it makes sense to use a plastic spatula spreader instead - the harened stuff will peel off and you can reuse them.
H.D. has the disposable bristle brushes for about 79 cents.
1999 Buick Park Ave Ultra
Head Unit: JVC KWHDR720
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