desk clock with tung oil

[Brian Keith]

Looking to put a finish on a clock and was going to go with tung oil. Should I use just this or should I put shellac or poly over it? Or should I go with some other finish? Thanks

[Steve Schoene]

The choice of finish is very subjective. An oil finish, which would be in the wood without any surface film has quite a different look that film finishes such as shellac or varnish.

For an oil finish I don't recommend the use of tung oil, assuming that you mean 100% or pure tung oil. It takes a very long time to dry so that you should have several days between each thin coat and it will take about 5 coats to achieve an even sheen. If you rush, there is the risk of it taking on a whitish "blush". It is likely these potential problems that causes manufacturers to offer "tung oil finish" products that are not tung oil. For example, Formby's Tung Oil Finish is actually a wiping varnish, with no tung oil. Other manufacturers offer mixes of oil and varnish under the same label. If you do want that in the wood finish, which can be very attractive, depending on the wood, I would suggest a mix of oil and varnish. Watco is one example, or you can make your own with equal parts of varnish, boiled linseed oil, and thinner.

Shellac is a film finish with a much different, though also attractive, look. It's naturally glossy but can be rubbed out to what ever sheen is desired.

Poly--polyurethane varnish--doesn't make sense for use on furniture, especially on pieces such as a clock that don't experience heavy abrasion. It's desirable properties are better achieved with a traditonal resin varnish or wiping varnish that will be more clear, and which will rub out more easily.