Blackened wood cure?


I have an outside letterbox which needs re-varnishing. Where the varnish has been weathered off the wood has gone a bit black - presumably with fungal attack. Has anyone any advice for me as to how to remove this staining before revarnishing? Sanding it off is not an option because it will be too deep, although a light surface sanding will take place anyway.
Rob Graham
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Depends on the species of the wood, and what has actually caused the blackening. If it is fungal atack you have got problems of a different sort, some woods "spalt" naturally, and others under a fungal action to become quite attractive. If its oak, that blackens on contact with iron, amongst other things, you cannot be definative without inspection, and even then not always.
For the record, and perhaps worth trying, the old method of removing stains was oxalic acid, if you can persuade the chemist t let you have an ounce or so. I think this is one that the law says you cant have now, and its years since i has or used any.
You can buy wood bleaches from the old fashioned pain shops as well.
Cheers John

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

The days have largely gone when pharmacists bought ingredients to mix their own "extemporaneous" products.
--
Graham.
%Profound_observation%
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

has
too
This is a problem suffered by wooden boat owners quite a bit. Sometimes sanding back and then using ordinary household bleach will lighten the colour enough, if not you just have to varnish over it.
The best, but most unhelpful, suggestion is not to let it happen in the first place by regular sanding and varnishing to stop water ingress to the wood. TonyB
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Rob,
Liberon sell a Wood Bleacher 125ml 3.80, or was last Summer when I bought some Sales No for local stockist - 01797 367555
Regards
Colin

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Thanks for your inputs, guys.
Rob
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Site Timeline

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.