My shellac finish clouded up on a humid day in Atlanta

I was finishing a walnut table last Tuesday when the humidity spiked, and the dew point was way too high for the shellac I was using. The whole surface went milky white before it could dry properly, and I had to strip it back to bare wood with denatured alcohol. Has anyone found a good dew point alert system or just a solid rule of thumb for when to call it a day?

3 comments

3 Comments

nathan_foster602mo ago

Check your local weather radar for moisture moving in.

taylorcarr14d ago

That thing about the hygrometer is smart-I read somewhere that woodworkers in the South basically live by those things during summer. I’ve seen people say the milky haze on shellac is actually moisture trapped under the finish, and once it’s there you're pretty much stuck sanding it all off. Honestly, respecting the humidity makes way more sense than fighting it with force.

nathanbennett2mo ago

Last Tuesday I was in my garage fighting the same fight with a shellac coat on a coffee table and man, that milky haze hit me like a brick. Honestly, I've started noticing this humidity thing goes way beyond woodworking. It's the same reason my phone screen gets foggy when I walk into my house from the heat, or why my car windows steam up in the morning after a rainy night. The dew point is just one of those sneaky physics things that ruins everything from paint jobs to just feeling comfortable in your own skin. I use a cheap little hygrometer from the hardware store that I keep on my workbench. Ngl, I just call it a day when the humidity hits 70 percent or higher, no matter what the weather radar says.