The best cleaning solution for wood cabinets is Murphys Oil Soap. It even puts a protective coating on your cabinets. The fragrance is very pleasing,too. Purchased at most stores.
Diluted vinager (sp? ) and water, either spray on wipe off, or using a soft cloth dampened with the mixture. Vinager cuts grease and dirt, and should not affect your varnish.
just use a very dilute solution of regular soap and water. i use dr. bronners magic soap or dr. bronners sal suds. you only need a little drop for a small sinkful of water.
After revising the furniture with a humid cloth, it suits to spray it with one shines furniture in aerosol or in cream, to extract sheen and to waterproof the surface.
