"Stained " oak

Tremlett 15

Tremlett 15

Well-Known Member
Joined
12 May 2009
Messages
326
Location
Bangor, N Ireland
Visit site
Cleaning "Stained " oak

Some of the internal doors ( heads, etc ) which are Oak veneer on plywood, finished I assume with "matt" varnish have become badly stained with wet/damp hands, towels & air, etc.....

001-39.jpg



002-33.jpg


003-39.jpg


A) I plan to strip the doors with Nitromors, then use Liberon wood bleacher to remove the "black" stains, then wash & let doors dry before re-varnishing.

B) Colour stain wood if required, then.... First coats of new varnish I was going to use "gloss" marine/external varnish & then finish with coats of "matt" varnish to match the rest of the existing internal woodwork........

is this all correct ???? or any other ideas/advise/recommendations.......

ps; my boat is a Bounty Sovereign 30 Sunbribge riverboat.
 
Last edited:
I have had good results with Ronseal interior varnish type stuff. Make sure you use the stuff thinned with white spirit and not the water-based rubbish. I have even used cork floor sealant!

I would NOT use a stain as I have had a lot of poor results with them. Streaky and uneven coating and generally "muddy" finishes. Fortunately these results were only on shelves at home and not anywhere where finish is important, like on the boat. The only stain that did give good results was Ronseal woodstain in antique pine, (again, an organic solvent product) which I used to "yellow down" some white pine shelves to make them tone in with a kitchen unit.

As you suggest, use a gloss product for the first few coats (and apply the first coat thinned with 10% thinner) with a final coat of satin finish.
 
Last edited:
Stained oak......

I suggest that you strip the varnish using one of the scrapers mentioned in previous threads,rather than nitromors, in order to keep a dry surface ready for the varnish. I also suggest Blackfriars clear polyurethane varnish - quick drying, and a hard durable surface. I find it helps to warm the varnish by placing in a pan of warm water whilst applying, this will help avoid any brush marks too.

ianat182
 
Don't know how thin your veneer is (note I do not say thick) but
I would be very careful using nitromors or scrapers unless you
really know what you are doing.
Use a sanding block with P120 ( OK P80 if the varnish is thick)
followed by P220. This will give you a good surface.
If the stain hasn't sanded out then treat with oxalic acid solution.
Choice of varnish up to you but I would build up with Epifanes Gloss
then apply topcoat of Epifanes Rubbed Effect.
Keeping varnish warm will certainly help as will the expense of a good brush e.g. Badger.
Cheers,
Chris
 
STOP.

Before you do any of this stripping stuff there may be a very easy solution for you.

Buy one of these for less than £4 from Lakeland
http://www.lakeland.co.uk/magic-eraser-block/F/keyword/magic+sponge/product/9009

I have loads of oak doors and they all had similar water stains. On a whim I tried this sponge thing on them and I could not believe it, the black stain literally wiped away.

This may sound like a Lakeland advert, but I am really just a customer. I just wiped the black stuff away. You can then touch up your varnish in the normal way.

Regards
 
SolentBoy said:
STOP.

Before you do any of this stripping stuff there may be a very easy solution for you.

Buy one of these for less than £4 from Lakeland
http://www.lakeland.co.uk/magic-eraser-block/F/keyword/magic+sponge/product/9009

I have loads of oak doors and they all had similar water stains. On a whim I tried this sponge thing on them and I could not believe it, the black stain literally wiped away.

This may sound like a Lakeland advert, but I am really just a customer. I just wiped the black stuff away. You can then touch up your varnish in the normal way.

Regards
Click to expand...

Thanks, just tried one which Mrs T15 had in the kitchen, ( did not know we had it ) it does remove the surface black but not the black thats in the wood ( via scaped/broken varnish )


also thanks to you all for replies to date, keep them coming.......
 
Oxalic acid should get rid of the staining in the first two photos but the marks in the third photo look more like scratches.

Be very very careful sanding ply, preferably don't. The decorative veneers can be very thin and you can go through it all too easily.

Contrary to what some of the others say, I wouldn't have varnish anywhere near my boat or even in my house.

Strip the old varnish with Nitromores, you don't normally need a scraper, use coarse (plumbers grade) wire wool. A stanley knife blade can be used in places but again very carefully. You will probably need several applications but you can reduce some mess by washing the Nitromores off with white spirit rather than water.

Once the old varnish is all off, you can use oxalic acid to remove the staining then wash it off with clean water.

When the wood is dry you can buff it with the same wire wool - sand it at your peril! If you do sand it, you will still need to buff it afterwards.

Don't try sanding the wood to try to get rid of every little ding and scratch it's too risky. Anyway, you'll ding it again after it's all back together.

If you want to darken it, (and I wouldn't blame you because oak doesn't look that good untill it's about two hundred years old) you can stain it with spirit stain (not water stain) and it probably will initially appear a little streaky but don't worry.

Next, start painting it with Deks Olja No 1, the penitrating oil and this will tend to dilute the spirit stain and the colour will even out. You will need to keep inpregnating it with Deks Olja over several days or weeks and each time you do it make sure that you wipe all the excess of the surface or it will go like burnt marmalade.

As with any oiled finish, it will take a time to work (at least a month) but it will be far better than any varnish, if you scratch it, you just put more on and every few years just give the woodwork a wipe over with a bit more oil on a rag.

Your wood got the black stains because the old varnish cracked and let in moist air.
 
wire wool and tannin

Oak even veneer has tannin in (an acid ) reacts with iron in any form and turns oak black . wire wool even tiny particles in grain remain in grain .

Test it small piece oak anything with iron in small amount of damp moisture
With turn it black over night . Use 3Msplastic wire wool type stuff I forget name similar to pan scrubs

The black on the doors probable caused by this where polish scrapped scratched off.

Incidentaly If you clamp and glue oak with waterbased glues pva etc any iron in clamps leaves black blue marks Hard to remove with hard sanding as they go into the surface. Certain typs abrasives dust can cause same

The tannin in Oak has allsorts of properties. You can stain bare Oak by fuming it.Cover and seal with something. A saucer of .880 ammonia inside the enclosure(watch your eyes wear a mask nasty chocking stuff )will change the oak to lovely brown colour over night (all glue must be cleaned off etc first)
 
Last edited:
You're absoltely right about the tainnic acid in oak but I've not had any problems with steel wool particles causing discolouration in the past. Having said that, the oak I've used it on has been when restoring old oak furiniture but that oak is pretty dark to begin with and the furniture does stay indoors.

If there is a plastic alternative to steel wool then even better and less risk.

I've been using the methods described in my previous post to restore the mahogany interior in my 33 year old boat including staining new wood to match the existing. some of it was done upto five years ago and it still looks good.

Fuming oak does turn it a lovely colour and could be done on all of the removable parts but wrapping the whole boat in plastic to do the bulkheads and other fixed parts may not be that viable.
 
Lesson No 1. Never varnish oak, it needs to be oiled and wax polished. When did you ever see good oak furniture varnished or even french polished? Never; if it has been treated properly. It is too porous and open grained.
By all means varnish it but your problems will return.
late-night-lochin is correct about the Deks
 
You must log in or register to reply here.

Share this page

Top