Putting varnish on exterior wood door

scuff it lightly with 220 grit or so and wipe it with clean water. Apply varnish in thin coats so you don't have runs.

I found a guy that specializes in finishing doors to have a wood grain appearance without using varnish. He does amazing work and it won't fade like regular stains do which have to be redone every year. He finished the door on my house and I was really impressed and pleased with his work.

Rice Sutton

I highly recommend checking out his site.

I have to redo my wood doors once a year. This is getting old. What's the difference between regular and marine varnish?

I have refinished a few exterior doors. If always use an oil based stain/ varnish as it lasts a lot longer than water based. If I don't know if the existing stain is water or oil based, I test it like in this tutorial and then strip it. It does take a while sometimes but is worth it long term.

Try Sikkens door and window stain. It's expensive but worth it

if the old varnish is cracking and peeling then you need to sand it good, if not then a light sand will do

I use Man o war marine spar varnish on my cypress swing and more recently on a pirouge and that holds up a lot better than the stuff you buy at Home depot, you can find it locally at Sherwin Williams, but I order it from Amazon