removing old black vanish tht has seeped into wood

Hi...we hired a fairly knowledgeable guy to refinish doors, frames, handrails, etc in our c.1920 home. Some wood had an almost black finish that has turned out to be a nightmare. He has sanded, bleached, sanded again...but traces of the black stuff remain in some parts and he is out of ideas and we're all desperate.
Could anyone suggest what else he could be doing? Many thanks in advance.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

This is usually do to water staining. I have tried many things and none of them have worked. I would love to know how to do it myself. It is a common problem on boats.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 13 Nov 2003 21:05:34 -0800, snipped-for-privacy@lipid.phys.northwestern.edu (Chuckles) brought forth from the murky depths:

Suggestions:
1) Sand off 1/8" (or more), refinish. NOTE: This could get tricky on hollow-core doors.
or
2) Replace wood, finish properly.
------------------------------------------------- - Boldly going - * Wondrous Website Design - nowhere. - * http://www.diversify.com -------------------------------------------------
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.