The use of Mineral Oil for finshing

[love2saw]

I have heard that someone used mineral oil as a finish. Has anyone tried that and can you put plywood pieces into mineral oil or would the layers come apart? I would appreciate some advice on this matter. Thanks.

[GrayBeard Phil]

1st welcome to the site. I hope you enjoy your visits.

Yes, I use mineral oil (from a pharmacy) for when I needed a food safe finish. I did some animal puzzles for very young children and I did a kitchen cutting board a long time ago. I no longer make puzzles for very young children.

I do not recommend you soak the wood in mineral oil. I recommend you flood the surface with the oil, let it stand for a minute or two, then wipe it off. And keep wiping off as the surface as the oil seeps back from the wood; checking about once every hour for about 4 hours.

It takes about a day for each coat to dry, and it takes at a minimum 3 coats.

Be aware there is a difference between the surface of the wood being dry to the touch and the finish being 'cured', many will argue that mineral oil will never 'cure.' I take the position that after about 2 months to 90 days, the oil and the surface of the wood do interact with the air to modify the wood fibers.

I have never heard of pharmacy grade mineral oil attacking or affecting the glue that bonds plywood. Don't mean it cannot, I just never heard of it.

I hope this helps.
Please post back, just would like to know why you are considering using mineral oil for a finish.

Phil

[sawdustus]

Welcome to our site.

Mineral oil is very safe for all woods and uses. Unfortunately, its drawbacks ourweigh its advantages.

Advantages - non-toxic - it is food safe but so are all other finishes once
they have stopped having an odor
does not change wood color, just darkens it a bit much the
way shellac, gloss varnish and lacquer do
easy to apply - see GrayBeard Phil's response
no toxic or irritating fumes to deal with
soap and water clean up

Disadvantages - never completely dries, just oxidizes and evaporates
wood must be recoated every few months or it is just as
though you never finished it at all
takes days for the wood to absorb enough to actually
protect the wood and by then you have wet wood
does not harden to form a sealed layer protecting the
wood from dings and scratches

Hope this helps.

George