final finish oak beams - advice

[dawson420]

Hi was hoping to get some advice from you lot, but posted my thread in projects like a donkey, If you read the thread on Oak beams needing some tender loving care, then eventually I ended up grinding all the woodworm damage areas off the beam, and now find myself with the pictures I have included, I've read through many articles on here, and picked up some notable information, especially the possible water staining from plastering, as that is the next stage in the project after re-boarding.

Does this mean i should use an oil to seal the oak beam, i dont want a gloss finish or sheen on the beams, and i don't want to colour stain them, and if this is the case what type/brand would you recommend, or would you say use something totally different, i have 4 more of these to remove this dark varnish from, any help would be great.

Cheers

Wayne

 

[aockenden]

We used a raw linseed oil on our original timber window lintels. Before and after are seen below. I love the rich matte color and lustre.

 

[Toby Newell]

We used a raw linseed oil on our original timber window lintels. Before and after are seen below. I love the rich matte color and lustre.

View attachment 12276

View attachment 12277

What is that wood? Large birch?

 

[aockenden]

I’m not sure. I don’t know my wood identification very well…

 

[Toby Newell]

Well, its not oak, elm, pine or pitch pine, so I suspect birch.

 

[aockenden]

Ok if you say so I’ll believe it. Is Birch any good?

 

[Toby Newell]

Ok if you say so I’ll believe it. Is Birch any good?

Lol. I am only going on experience, how old is your cottage? Those are the only wood species I have ever seen in the UK used as beams. There may be others that I haven't seen yet.

I only discovered birch recently, also with bark, used as joist in a 400 yr old cottage in Kent, it was insanely hard! (I had to cut some noggins into it) And appeared to have resisted pest attack well (it's actually quite prone to pest attack and spalting)

I must admit to feeling a bit stupid at my surprise but I never really worked with it before (in the solid) Probably having an extended senior moment I was perplexed because I thought I was dealing with a softwood. It felt every bit as hard as old oak, if not more so. I suspected beech, but cut out enough to see that the grain didn't match. Strangely the members were all very waney edge with bark intact and very roughly cut on the sides, literally looked like someone had lopped off a few branches.

The sapwood, centuries old remains a light yellow cream, the heartwood is more of a red orange caramel. Your lintel looks like a waney edge sapwood face and it looks like a wonky birch bough. Oak lintels are often straighter and normally you can see at least some heartwood poking through which would be dark brown by now. (Oak has a much thinner layer of sapwood than birch)

So, very hard and after I researched, potentially stronger than oak, so yes, apart from it's slightly greater propensity to rot, it's a very rare but strong find.

My client asked the same thing, I told him it was bloody hard.

 

[Toby Newell]

Hi was hoping to get some advice from you lot, but posted my thread in projects like a donkey, If you read the thread on Oak beams needing some tender loving care, then eventually I ended up grinding all the woodworm damage areas off the beam, and now find myself with the pictures I have included, I've read through many articles on here, and picked up some notable information, especially the possible water staining from plastering, as that is the next stage in the project after re-boarding.

Does this mean i should use an oil to seal the oak beam, i dont want a gloss finish or sheen on the beams, and i don't want to colour stain them, and if this is the case what type/brand would you recommend, or would you say use something totally different, i have 4 more of these to remove this dark varnish from, any help would be great.

Cheers

Wayne

View attachment 12274

View attachment 12275

Lol, you literally removed the entire flaky sapwood pastry, still, the sausage looks good. Was it necessary to be that harsh? I don't see any galleries in the heartwood.

 

[Toby Newell]

Strangely it already looks plaster burnt, very odd, like someone has put alkali stripper all over it, that is not a natural aged oak heartwood colour, maybe it's poor white balance. Beams don't need anything, they last several centuries with no coatings. It's purely for aesthetics, most people would want to use an oil finish or shellac and wax being easily strippable and breathable.

I see in your original post it was coated in plaster, seeing as the sapwood was just effectively a big sponge and it was obviously very damp then yes, all that dark grey colour is chemical 'plaster burn' stain. You might lighten it with a boiling oxalic acid bleach wash.

 

[Toby Newell]

Ok if you say so I’ll believe it. Is Birch any good?

But I can possibly be more authoritive if you can take better close up photos in better light, even if the surface is a bit dirty.

 

[aockenden]

Lol. I am only going on experience, how old is your cottage? Those are the only wood species I have ever seen in the UK used as beams. There may be others that I haven't seen yet.

I only discovered birch recently, also with bark, used as joist in a 400 yr old cottage in Kent, it was insanely hard! (I had to cut some noggins into it) And appeared to have resisted pest attack well (it's actually quite prone to pest attack and spalting)

I must admit to feeling a bit stupid at my surprise but I never really worked with it before (in the solid) Probably having an extended senior moment I was perplexed because I thought I was dealing with a softwood. It felt every bit as hard as old oak, if not more so. I suspected beech, but cut out enough to see that the grain didn't match. Strangely the members were all very waney edge with bark intact and very roughly cut on the sides, literally looked like someone had lopped off a few branches.

The sapwood, centuries old remains a light yellow cream, the heartwood is more of a red orange caramel. Your lintel looks like a waney edge sapwood face and it looks like a wonky birch bough. Oak lintels are often straighter and normally you can see at least some heartwood poking through which would be dark brown by now. (Oak has a much thinner layer of sapwood than birch)

So, very hard and after I researched, potentially stronger than oak, so yes, apart from it's slightly greater propensity to rot, it's a very rare but strong find.

My client asked the same thing, I told him it was bloody hard.

Hmmm interesting. I didn’t know anything was stronger than oak! Our cottage is either 200 or 250 years old (depending if you ask my neighbor or the surveyor who we paid before purchase), located in central wales. Here’s a pic of both of our 2 original timber lintels if that’s enough for you to tell?

 

[Toby Newell]

Ah ok, not that old then. Still not clean enough for me to identify via figure or grain on the surface but very light and I cannot see any quarter grain figure, close up photo of the bark please...

I can only see a sliver of bark at an oblique angle, but looks like a very thin bark (oak is thicker) and lines seem to be circumfrential rather than longitudinal, looks like birch bark from here. And yes, oak is strong but a few woods are stronger (in UK, ash and birch being two of them) ash is never used as it rots incredibly easily but is much tougher than oak and better used for tool handles, all my oak chisel handles get mashed. Birch is rarely used as it only comes in small section but is just as strong as oak, stronger in fact, but slightly less dense, as well as small section it warps and cracks more, it's very hard and has good bending strength. You cannot judge a wood on it's material 'top trump' numbers alone. Oak constantly moves yet cracks and warps less and is fairly resistant to rot and pest attack and comes in massive sections which is why overal it is the best wood.

 

[aockenden]

Ah ok, not that old then. Still not clean enough for me to identify via figure or grain on the surface but very light and I cannot see any quarter grain figure, close up photo of the bark please...

I can only see a sliver of bark at an oblique angle, but looks like a very thin bark (oak is thicker) and lines seem to be circumfrential rather than longitudinal, looks like birch bark from here. And yes, oak is strong but a few woods are stronger (in UK, ash and birch being two of them) ash is never used as it rots incredibly easily but is much tougher than oak and better used for tool handles, all my oak chisel handles get mashed. Birch is rarely used as it only comes in small section but is just as strong as oak, stronger in fact, but slightly less dense, as well as small section it warps and cracks more, it's very hard and has good bending strength. You cannot judge a wood on it's material 'top trump' numbers alone. Oak constantly moves yet cracks and warps less and is fairly resistant to rot and pest attack and comes in massive sections which is why overal it is the best wood.

I actually don’t think there’s any bark left on either of them. You must be seeing something else. The middle lintels over each window are both wood as well and they both do have bark on them still. Not sure if that’s worth seeing?

 

[Toby Newell]

I actually don’t think there’s any bark left on either of them. You must be seeing something else. The middle lintels over each window are both wood as well and they both do have bark on them still. Not sure if that’s worth seeing?

What are the stripes underneath? Some sort of plastic matting? Well if they look the same then photo the bark. From the wood I cannot tell as it is too dirty still. The fine cracks could be quarter grain flecks in oak.

 

[aockenden]

What are the stripes underneath? Some sort of plastic matting? Well if they look the same then photo the bark. From the wood I cannot tell as it is too dirty still. The fine cracks could be quarter grain flecks in oak.

This is the only pic I got before covering the underside of all lintels with a stainless steel mesh lath in preparation for replastering with hemp-lime which makes it very difficult to photograph now.

The stripes you are seeing underneath are probably the leading edge of the metal lath mesh.

 

[Toby Newell]

This is the only pic I got before covering the underside of all lintels with a stainless steel mesh lath in preparation for replastering with hemp-lime which makes it very difficult to photograph now.

The stripes you are seeing underneath are probably the leading edge of the metal lath mesh.

View attachment 12352

Ha! Thanks, doesn't help. Yes thought the stripes looked too uniform. Maybe a daylight close up photo of the first lintel. Maybe what I thought were micro cracks were infact quarter grain flecks in oak.

 

[aockenden]

Ha! Thanks, doesn't help. Yes thought the stripes looked too uniform. Maybe a daylight close up photo of the first lintel. Maybe what I thought were micro cracks were infact quarter grain flecks in oak.

Well thanks for trying anyways. I think I’ll just clean them up further at some point in the future and then send you some proper updated pics in better lighting.

 

[Toby Newell]

Lol poor guy we totally hijacked his thread