Cabin sole finish
The operative word in VIEXILE''s reply is definitely "carefully" since you say you''re working with veneer. Although the veneer that was around some 20 years ago probably is somewhat thicker than that available today you should try to ascertain how thick the actual veneer layer is before attacking the old varnish. If you do happen to sand through the veneer it is almost impossible to effect a nice looking repair short of replacing the veneer. You may want to try a chemical stripper although this can break down the glue holding the veneer layer or you could try to soften the old varnish with heat but this can cause the veneer to bubble if too much heat is applied. Before starting on the sole you might test the method you choose on an area that is not too obvious. A scraper generally works well but you definitely want to keep it sharp like VIEXILE said. If you do scrape, buy several shapes and sizes, don''t scrimp, buy good scrapers and you may want to round the corners of the blade with a file to help prevent inadvertant gouges. When you sharpen the scraper(s) do it off and away from the boat or be extra careful about capturing the filings. They are virtually invisible and any left laying around will cause multitudes of tiny rust spots that are almost impossible to remove. When I wood my teak, I use about ten scrapers and take them to the garage to sharpen them. If you''re around other boats, mind where the wind will take your filings.
Good luck and have fun. Remember preparation is 90% of the job; whatever finish you choose, laying it on a properly prepared surface is the fun and rewarding part.