The StopLossBag™ allows you to help preserve the fresh off-the-shelf quality of wood finishes. When a fresh can is first opened, it has the ideal solvents to solids ratio for brush application. Evaporation and oxidation from repeated opening and closing of the same can leads to a thickened and degraded finish, and eventually the varnish skins over inside the can making it unusable. And, now you’ve got hazardous waste.
The normal practice of opening a can of wood finish and dipping a brush directly into it, while easy, can have unfortunate consequences. Evaporation occurs all the time the can is open, changing the solids to solvent ratio. Invariably, some finish gets into the seal ring around the edge of the can, and when resealed begins to set up compromising the seal of subsequent closings of the can. The can now has oxygen in it from the air which replaces the finish used, and that reacts with the remaining varnish.
By transferring the finish from the original can into a StopLossBag™, you will be able to reduce both evaporation and oxidation, allowing the finish to remain closer to its original quality for an extended time and allowing you to use more of the finish you’ve paid for. The bag is reusable.
Begin transferring the finish to the bag by using a turkey baster. (You may want to blow a puff of air into the bag the first time it is filled.) A turkey baster tip will fit into the spout of the StopLossBag™. For easier filling, the clear grey filler tube makes a connection between the bag’s spout and a medium size funnel. The filler tube comes with a red adapter tube to help connect to larger funnels. Be sure to push the grey filler tube fully onto the unthreaded portion of the spout. Elevating the funnel by using a filling station stand can help (see filling station here). I use a turkey baster from the supermarket to remove enough of the finish to allow pouring without spilling. As the StopLossBag™ fills, the bottom gusset expands allowing the bag to stand upright on its own. After filling, remove the filler tube and/or adapter tube from the funnel and wipe away drops of finish so it won’t harden in the tubes. To extend the life of your filler tube and adapter tube, be sure to remove them from the funnel so the flexible plastic can “relax” during storage. Some oil-based varnish users report good results by keeping a small bottle of naptha or paint thinner to dip them in before standing them upright to dry on a paper towel. For shellac, an alcohol bath is effective, and water should be used for water-based varnishes