sanding sap wood

[Dave Fritz]

Making some walnut natural edge bowls and find when sanding the heart wood darkens the sap wood. How do you sand to keep the sap wood as light as possible?

Thanks for your help.

Dave F.

 

[MichaelMouse]

Mostly that's dark dust scrubbed into white pores. Take a power brush to the sapwood that's darkened already and see what you can do. A bit of shellac in a 2# cut seems to shed well enough when I use it on pristine sapwood.

 

[john lucas]

I put thinned lacquer on the white wood before every grit of sandpaper. this helps fill the pores and keep the sanding dust from the dark wood out of it. I then blow it off between grits and apply a little more. Sanding sealer or shellac also work.

 

[hockenbery]

Sealing works fairly well.

Sometimes my final solution is to bleach the sapwood. This is often necessary with HFs and natural edge bowls turned from wet walnut. I usually get some staining in the sapwood from the water in the heartwood.
2 part bleach from Klean strip applied carefully to just the sapwood pops the white back better than it was.

You can also get nice contrast effect on walnut by turning a bead and bleaching the bead to sort of a blond color.



Al

 

[John Jordan]

Use an air hose and blow as much free water as you can from the sapwood, and whatever will come out of the heartwood. It works.

John