What grit sandpaper

[Texsun66]

I am sanding and re-waterproofing a redwood planter.
What is the highest grit paper I should use that will provide a smooth surface yet allow the wood to absorb the waterproofing?

thanks,
Andy

[cabinetman]

I am sanding and re-waterproofing a redwood planter.
What is the highest grit paper I should use that will provide a smooth surface yet allow the wood to absorb the waterproofing?

thanks,
Andy

Redwood isn't that hard, and ordinarily I wouldn't go past 150x -180x. You could try a sample spot on the bottom with 220x. If that is too smooth re-sand with 180x. If you can find an "open coat" paper, try that, you might like it. It's more flexible and doesn't clog up like garnet.
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