Tung Oil / China wood oil on old timber

[D700Doug]

I managed to pick up an old table for the studio that someone was throwing out . After being told off for bringing home more rubbish and cleaning it up I am now told it will go well in the lounge room next to the red cedar dining table

It has cleaned up well but the top has some hairline cracks from drying and bending slightly.
( the table and timber is probably about 1930s 1940s and probably stored in a shed for many years )

I was thinking an oil finish would look good and possibly nourish the timber

has anyone used tung oil as a furniture finish ?

Anything to watch out for ? Any hints or warnings ?

cheers doug

[BobL]

I managed to pick up an old table for the studio that someone was throwing out . After being told off for bringing home more rubbish and cleaning it up I am now told it will go well in the lounge room next to the red cedar dining table

It has cleaned up well but the top has some hairline cracks from drying and bending slightly. I was thinking an oil finish would look good and possibly nourish the timber

( the table and timber is probably about 1930s 1940s and probably stored in a shed for many years )

has anyone used tung oil as a furniture finish ?

Anything to watch out for ? Any hints or warnings ?

Make sure you test it out before hand as I found it darkens most timber significantly. I find Danish oil is usually better.

[D700Doug]

given the price of a tin of oil I may go the danish oil option.

I will ask the management if she prefers a lighter or darker finish

[Christos]

Danish oil contains tung oil. Should also have other additives to help in the drying process. I have not used tung oil before but have been told it takes a long long long time to dry.

[Wizened of Oz]

I have not used tung oil before but have been told it takes a long long long time to dry.

Not in my experience. Even without added dryers it dries in a reasonable time. Maybe slower in a climate colder than here.
However I mix about equal parts pure tung oil and mineral turpentine and add a little Terebine to speed up drying. On summer days I can put on two coats in one day.

[D700Doug]

Wiz do you find much of a colour change ?

You use mineral turps not natural ?

===========

Thanks all for the advice so far all

[Claw Hama]

Checck out the thread on The Maloof Mix.

[D700Doug]

sounds like an interesting mix and I think I have most of the ingredients

does polyurethane = clear exterior varnish ?

Derp

[Stewey]

does polyurethane = clear exterior varnish ?

In a nutshell: NO!

Both are generally clear though.

Varnish is an oil-based product which dries by oxidation, i.e. it needs oxygen, and the process is nonreversible. Exterior varnishes have UV inhibitors in them.Varnishes are generally pretty flexible & elastic. Thin with mineral turps.(Think of 'Estapol' or Feast Watson Exterior UV-clear gloss)

Lacquers dry by evaporation of the solvents (usually lacquer thinners), and the process is reversible. i,e, pour lacquer thinners back on the dried lacquer & it'll dissolve back into solution again. No 'strength' in the film. (Think-automtoive clears from the1970s & modern fast dry spray-on furniture clears.)

Urethanes and polyurethanes are a different animal.
The 2-pac automotive paint clears used these days are urethanes-they cure rock-hard & glassy-glossy. There's a paint/clear & a catalyst, usually isocyanate-based (=VERY poisonous!). It is lind-of like mixing epoxy glue in two parts. When cured, it is permanently set-non-reversible. You need appropriate 'reducers' to thin it.
Generally very 'strong'.

Some 2-part floor paints are polyurethanes-and can be a bit more 'plasticy'. Not all have UV stability though-READ the LABEL & think twice before trusting the salesman!

[Claw Hama]

Varnish does still work and is the third part of the original mix. I use whatever I have on the shelf at the time mostly.

Stewey pretty sure both Estapol and FW ext are polyurethanes. I think most Varnish these days are polys.

[A Duke]

What do you think the pol in Estapol stands For? If there is pol in the name it's almost sure to indicate polyurethane, at least that's my understanding.
Regards

[D700Doug]

Cabot Stains Water-borne Polyurethane Product | Cabot

this stuff

[Crunchie]

What do you think the pol in Estapol stands For? If there is pol in the name it's almost sure to indicate polyurethane, at least that's my understanding.
Regards

Do a little checking before you assume the poly is always Polyurethane. Poly is a prefix meaning "many". The starting materials are monomers and become polymers after polymerisation. Hence Polyethylene (Polythene), Polyester (is Esta - pol a word play on this?), Polymethylmethacrylate (Acrylic) and, just for fun, Polyhexamethylethyleneadapamide (I'll let you work that one out)

[D700Doug]

Do a little checking before you assume the poly is always Polyurethane. Poly is a prefix meaning "many". The starting materials are monomers and become polymers after polymerisation. Hence Polyethylene (Polythene), Polyester (is Esta - pol a word play on this?), Polymethylmethacrylate (Acrylic) and, just for fun, Polyhexamethylethyleneadapamide (I'll let you work that one out)

Or it could just contain crushed parrots?





Sorry

[Wizened of Oz]

Wiz do you find much of a colour change ?

You use mineral turps not natural ?

Almost no colour change but it "pops" the grain wonderfully. Even when finishing with shellac I first give a coat of tung oil to accentuate the grain and I make up my grainfillers with tung oil.
But I don't use oils on dark red timbers, it turns them muddy-looking.
Yes. I use mineral turps. I'm not rich enough to use gum turpentine unneccessarily. The turps is just a carrier to help with spreading and to increase penetration. It simply evaporates away.
You probably know already that when coating with oil you wipe off the surplus before it is tacky (say, after about 20 minutes). Rub down with a fine abrasive (0000 steel wool or equivalent) after every second coat. Use 6 or more coats.
In his "A Polishers Handbook" the owner of these forums quotes (I think) Vic Wood as saying an oil finish should then be recoated once a week for a month, then once a month for a year, then once a year thereafter. Might be a bit excessive but you get the picture if you want perfection. I tend to be a "once-in-a-while" recoater.
And be careful of what is claimed to be tung oil. Once I allowed myself to run out and bought "Pure Tung Oil" from a local paint store. When I got home and read the label it showed it was 60% turps. Other brand name "Tung Oil" might be thinned polyurethane.