We purchased Pella sliders and put stain on them. The contractor then accidentally sprayed varnish on prior to the sealer. He has now sprayed the sealer over the dried varnish and wants to sand before the final coat of varnish is applied. Is the wood sealed and how aggressive should we be with sanding?
Varnish is its own sealer. Typically a seal coat of varnish is applied, allowed to dry, lightly sanded, then re-coated with the same varnish.
The wood is fully sealed. Go ahead and lightly sand, fine (180 grit) sanding sponge, remove the dust and apply your final coat.
i used a stain and polyurethane blended product on my wood gate. I would like to use a marine varnish over the top for better protection. Is this advisable and if so, what tips do you suggest?
On the sliders: Yes, the Varnish seals the top cote of Stain… a Sealer is really NOT necessary before a second coat of Varnish, but won’t hurt… be gentle with sanding before applying a second coat of Varnish… BTW (spraying is not as good as brush or roll application) Good Luck!
On the wood gate: Using a Stain-Varnish combo product is tricky to apply for amateurs (may cause sags or runs) but yes applying a Spar (marine) Varnish will add more weather protection, if applied correctly (always apply and layout with a brush in the vertical direction, as opposed to just spraying)… Good Luck!