Fixing solid oak door lining

[Aged Dim]

I have come to this fairly late in the day, but am concerned that everyone has addressed the aesthetics of concealing the fixings, nobody has mentioned that oak is acidic and is incompatible with steel screws and nails, even galvanised, the zinc is stripped away during insertion. If you are going to use screws, they must be stainless, preferably A4.

[ayjay]

If you are going to use screws, they must be stainless, preferably A4.

......or Brass.

[Job and Knock]

But here's the rub - on exterior work or interior work where moisture ingress was even a minor possibility I'd heartily agree with you, for a concealed screw in a dry household environment is it going to make any real difference? Especially as modern "steel" screws are almost all zinc coated or passivated and resist rusting much better than the old plain bright steel screws of yore (in fact to get plain, untreated screws these days you need to special order them and the available size range is limited). At the end of the day whether the screws were put beneath pellets or a door stop they would then be away from any moisture in the environment and unlikely to corrode and produce the inky black iron stain (the oak itself should have been kilned to about 8% and central heating will bring that down further over time). TBH stainless steel screws can be a royal PIA to deal with because they are so much softer than hardened steel ones and heads regularly strip out under only moderate force even with adequate piloting

BTW that staircase in my avatar (plus the other 5 flights on that site) was all in 1in (25mm) thick solid T&G oak cladding, screwed and pelleted, and we did use A2 stainless fasteners throughout. But then, despite the building being a public space, the stairs are heavily used by people who may have just walked in off the street and could well have wet footwear and/or dripping raincoats, etc so I was being "risk averse" at the time I installed it

[Aged Dim]

I am glad you used stainless steel screws, had you used coated mild steel the story will eventually be different. The tannic acid in the oak will eventually corrade the steel away, gravity and applied force will do the rest. Where there is a the likelihood of a claim being made against public liability insurance, there is a strong chance that the insurer will try to off-set their liability with a claim for negligence! Not worth scamping the work, for a few bob!

[Job and Knock]

Not worth scamping the work, for a few bob!

Yes, I know, that much I did absorb from my mentor nearly 50 years ago

[OchAye]

I am glad you used stainless steel screws, had you used coated mild steel the story will eventually be different. The tannic acid in the oak will eventually corrade the steel away, gravity and applied force will do the rest. Where there is a the likelihood of a claim being made against public liability insurance, there is a strong chance that the insurer will try to off-set their liability with a claim for negligence! Not worth scamping the work, for a few bob!

Not to worry but the thread you woke up was some 3 years old By now the door frame is fixed etc.

[Dave54]

But here's the rub - on exterior work or interior work where moisture ingress was even a minor possibility I'd heartily agree with you, for a concealed screw in a dry household environment is it going to make any real difference? Especially as modern "steel" screws are almost all zinc coated or passivated and resist rusting much better than the old plain bright steel screws of yore (in fact to get plain, untreated screws these days you need to special order them and the available size range is limited). At the end of the day whether the screws were put beneath pellets or a door stop they would then be away from any moisture in the environment and unlikely to corrode and produce the inky black iron stain (the oak itself should have been kilned to about 8% and central heating will bring that down further over time). TBH stainless steel screws can be a royal PIA to deal with because they are so much softer than hardened steel ones and heads regularly strip out under only moderate force even with adequate piloting

BTW that staircase in my avatar (plus the other 5 flights on that site) was all in 1in (25mm) thick solid T&G oak cladding, screwed and pelleted, and we did use A2 stainless fasteners throughout. But then, despite the building being a public space, the stairs are heavily used by people who may have just walked in off the street and could well have wet footwear and/or dripping raincoats, etc so I was being "risk averse" at the time I installed it

I've seen plenty of old oak furniture with plain steel screws that are perfectly OK, with just the rust you would expect from being in virtually any timber. Quite a nice oak dining table, made by my wife's uncle in the 20s, with the top fixed on with steel screws, no problems with that, the top has been taken off, and replaced several times with the original screws. We have a 17th Century oak chest as well. Iron nail fixings, (OK a bit different to steel but still ferrous) They appear to be holding up as well, with little staining around them. (And still the original wire hinges)
As you say, all OK as long as the wood is kept dry.