Chestnut Stair Handrail and Baluster Finishing

[Lisa Starr]

Hi All -- I'm usually in GWW and Off Topic, but need your expertise. I have an antique (circa 1838) stairway with American Chestnut (clear, not wormy) Handrail and Balusters. At the moment, the Balusters and handrail have a tung oil finish. Due to do the construction method, I need to install the Balusters prior to painting the treads and risers. Will the tung oil finish be sufficient to prevent the paint from wicking into the balusters or do I need to put something like Shellac, Varnish or Poly over the Tung Oil? If I need to a top coat, what do you recommend? The soft look of the existing finish is important for me to maintain. TIA

[Jim Becker]

Is there no way that you can partially finish the other components before assembly? If you can, simple masking as you do "the last coat" might work. If you feel you need to top coat, use a matte sheen finish to preserve the soft look and feel of the wood you've used the tung oil on.

[Lisa Starr]

Jim - What product for the top coat?

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The balusters fit into the dovetails on the side of the steps and then the nosing is put on. The only way I can see to eliminate the line is to finish the entire thing assembled. Other ideas?

[Jim Becker]

With the tung oil, I'd probably opt for an oil based matte varnish, despite the fact that I'm not a fan of oil based top coats, and the reason is adhesion. Using a water borne may force you to have to do a wax free shellac barrier coat to insure good adhesion and that's an extra step. That said, there is still the case for just being really careful when painting because the tung oil...if you let it cure...does seal the wood. It's a drying oil. It's more about pore filling and even with some varnish, you can still get paint into pores for something like chestnut (and oak and walnut and...) so in the end, it's about brushing skills.

Now...based on your photos....pull off the nosing and pre-paint it along with the stairs. Carefully clean the edges that will join together between the nosing and the treads so the go together nearly invisibly. Install the balusters into the dovetails. Apply the nosing, fill the holes from the brads or other fasteners you use and touch up the paint on the nosing to hide the fasteners. Very low risk and you don't need to go to so much trouble with the balusters.

BTW, I always pre-finish things like shoe molding prior to installation because...floors. The nosing on that stairway is pretty much the same situation, except instead of "floors" you have "balusters".

[John TenEyck]

I would finish the balusters as you want, wrap them in masking tape where they meet the treads, then assemble and finish the treads as you want. Doesn't look like a problem to me. Another option is to pull of those nose moldings. That would allow you to prefinish the treads and risers. Then just reassemble.

John