Re: Alternative to spray stain finishing?
A 6x9 inch hole is actually a pretty darned good size, access really isn't going to be limited to get a hand, rag, or small brush in there.
I would recommend using a stain product first, then applying your sealer/top coat. This helps the project to maintain it's color as it starts taking on the battle scars of life. Because of the intricacy of all those pockets and corners to deal with, I'd recommend using a gel stain, it is slower acting, giving you plenty of time to both get it applied and get the excess wiped down before the wood takes on too much color. Before you ever stain anything you should always practice on a scrap of the same material to perfect your application technique, as well as know how long to leave the stain before wiping the excess down. NEVER NEVER NEVER leave a stain rag wadded up, as it can self ignite. ALWAYS ALWAYS ALWAYS lay used rags out flat to air dry, or dispose of in a fireproof/fire safe manner.
Applying your top coat is likely to be your bigger challenge. I would be concerned that using a sprayer or aerosol cans would be tough in the tight quarters, without causing pooling and runs, brushing or wiping may be your best bet. As much as it hurts to cut up good tools, you may want to consider cutting the handle off a good quality brush that is suited to the type of finish you are applying. You can either just hang onto the ferrel of the brush or you can attach a handle that is roughly at a right angle to the brush head. Another option would be to use a finish that can be hand applied/rubbed, such as an oil finish.
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