Romance route with lumberjack is not existing yet. There's not much to do with him. The most things to do are with Bernard (Shopkeeper) for now.
If it comes to blacksmith you can rimm him, you can fuck him (Only for males, the libido must be at least 50 and character must have at least 12 strength for it to success). If you have love potion there will be also another option in the forge.