I will be finishing about 800 sq ft of 1×6 pine T&G prior to installation on a very high (24′)cathedral ceiling. I would like a very light or natural low gloss finish. What is the best product choice and a good technique for finish application? Relatively quick drying would certainly be a plus. Have heard that pine can be difficult. Do I need to prime or seal the back side too?
The best way to deal with this project is to have a shop area with a stain and finish application area and saw horses for the drying area, you can also use 5 gallon buckets with 2×4's for the drying area. You can also stain and finish outside then carry the T&G wood into the drying area.
For staining I like to use a lamb's wool stain pad. Wipe on the stain then wipe off with clean white rags. The finish should be sprayed, either with a airless paint sprayer (311 or smaller tip) or an HVLP. The airless is much faster and a good choice for horizontal spraying.
The clear finish I like is Coronado Aqua Plastic. It is a water based urethane that dries quickly, less than 1 hour to re-coat. And, is available from dull flat too high gloss sheen's. Other products to use are Sher-Wood Aqua Plus by Sherwin Williams or Varathane water based polyurethane.
Pine is a difficult wood to stain if you use a medium or dark wood stain. It has a tendency to be a little blotchy. For a light stain you shouldn't have any problems. Test your stain on the back of a board before staining the entire batch. It is also to apply one coat of finish to the backs of the T&G pine to seal them against moisture.
T&G already installed, used conditioner and still got a really blotchy finish. We sprayed both. Should we use tint in the lacquer?
You can use a tinted clear wood finish. This could help, but it will also darken the color. Use a lacquer only if the original finish is a lacquer. Never put lacquer over any other type of clear wood finish, the solvents are way too hot and will cause cracking or bubbling. Polyurethane can also be tinted a little.