Does oiling both faces really make a difference?

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ol_london

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I know the theory says you should oil both faces of a top or else it will warp the wood. But is that actually true? It seems a lot of time and product wasted if it isn’t really necessary.
Has anyone actually experienced wood warping because they only oiled the top face?
(I’m talking Osmo wood wax finish if that matters).
 
I’d always do both sides if possible, however I really think it’s the environment and construction, rather than the non oiling which causes problems.
 
Most traditionally made furniture only has finish on the outside and some pieces have survived many
centuries.
It might warp for a variety of reasons, but lacking a finish on one side is not a major one.
 
The bottom line is if you don’t do both sides & in does warp it’s a lot more time, effort & expense putting it right rather than doing both sides in the first place.
Can you guarantee the environment the item is going into? Wood can warp even if you have coated both sides, whilst we try out best to eliminate wood movement the chance is still there so why would you add to that chance by not coating both sides.

I‘m sure there are instances where folks have got away with only coating one side but that could be luck as opposed to anything else.
 
Most traditionally made furniture only has finish on the outside and some pieces have survived many centuries
I don’t disagree but how many of those pieces are still flat & have not suffered movement, certainly a lot of the old items that come into my shop have sections that definitely aren’t the same shape as the day they were made. I’m not saying this is detrimental to the furniture, it can be said to add character but it isn’t what I’d like in my own furniture.
 
I think maybe a quick coat on the underside then and not too fussy wasting time on minor patches etc is the way to go.
 
most old furniture isn't made from slab cut staves in fast grown or forced timbers.
Yes I've seen sides cup massively from not being oiled on both sides before install, normally when a mate has decided to fit his own kitchen and either didn't know or didn't care. cost my sister a fairly large amount for brand new sides because they weren't fitted in accordance with the manufacturers guide.


but hay, crack on, not like the sides cost 10x the oil you saved. :)
 
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The main reason to seal both sides is to control moister in air if one side not sealed this creates different surface condition leading to warping. Even if you look at standard worktop they always have a waxed paper on under side.
 
Most traditionally made furniture only has finish on the outside and some pieces have survived many
centuries.
It might warp for a variety of reasons, but lacking a finish on one side is not a major one.
Most traditionally made furniture is made from single pieces of properly sawn and seasoned timber and has spent sometimes centuries without central heating stabilising.
 
One thing of course that's been missed - it doesn't matter what what the underside is sealed with - it could be old gloss paint.
Like Novocaine I've seen tops over half an inch hollow where the back's been left unsealed. Seal it. It's better to regret something you have done than something you haven't.
 
Thanks all. In future a dash of oil to seal it, not too much fuss as it won’t be seen, sounds sensible.
 
I m still a Danish oil person after all these years.
I believe that oiling all round seals the wood and protects from moisture ingress. Oil solids or micro balloons?
I know myself that that is probably incorrect but to date I have never experienced an explosion from anything I've made where the base timber could have held moisture.
But, I do rough plane then bring the wood inside, placed underneath beds to aclimatise for long periods of time.
I use Ronseal poly on table surfaces protection on top of Danish oil, again after a longish drying out time between the two applications. Only on the show face.
 
don’t disagree but how many of those pieces are still flat & have not suffered movement, certainly a lot of the old items that come into my shop have sections that definitely aren’t the same shape as the day they were made. I’m not saying this is detrimental to the furniture, it can be said to add character but it isn’t what I’d like in my own furniture.

I think we are lucky that the relative humidity stays quite stable in the UK. Unlike the USA.
So long as you go through the proper process of climatisation with projects before finishing all sides there shouldn't be a problem.

Hark he says after seeing a table brought back from Ireland where an oak table top split and had to be replaced when the client did not specify she had an aga going day and night in an enclosed small kitchen.
 
Unless you encapsulate it in some plastic/ epoxy type finish, there will always be an exchange of moisture
with the surrounding environment. The greater this exchange, the more wood moves. Sometimes it will warp.
Most finishes can not prevent this. Perhaps they might slow it down a bit.
I think central heating has caused more damage to old furniture than any lack of finish.
I agree though, finishing both sides probably can' hurt.
 
These sort of questions come up a lot. The main reason is people know next to nothing about the nature and make up of the material they are using. Too many people nowadays have probably never lived in a home without central heating nor had non manmade material furniture. They do not know that real wood behaves very differently to MFC MDF etc nor why. So when they come to this hobby they think the tried and tested methods are old wives tales/urban myths etc.
As i have said before, before you buy a tool buy a book preferably one about wood and NOT 50 shades of grey

edit
not added due to typo
 
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Has anyone actually experienced wood warping because they only oiled the top face?
Years ago I had a kitchen worktop that I oiled on the top only and it warped (actuallu cupped) badly - but how do I know why it warped? Sure, it could be because of my oiling practise but who knows if it would have warped anyway?

BTW, If you think it was definitely my fault, that's OK. I can take it. But please don't tell SWMBO.
 
About 6 years ago, during the process of installing a new kitchen, I removed a set of wooden worktops from the existing kitchen that had only been sealed/oiled on the top and front edge.
They were really bad and out of shape. A kitchen environment with all that heat and moisture & changes in temperature is just about one of the worst areas for wooden worktops.....Especially if they haven't been sealed correctly.

It may seem a thankless task to seal all the non seen surfaces, but it will be worth it in the long run.
 
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