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D700Doug
8th February 2012, 07:04 PM
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 :D

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
8th February 2012, 07:06 PM
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 :D

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
8th February 2012, 07:12 PM
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 :B

Christos
8th February 2012, 09:28 PM
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
8th February 2012, 10:34 PM
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
8th February 2012, 10:39 PM
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
8th February 2012, 10:40 PM
Checck out the thread on The Maloof Mix.

D700Doug
8th February 2012, 10:57 PM
sounds like an interesting mix and I think I have most of the ingredients

does polyurethane = clear exterior varnish ?

Derp :D

Stewey
9th February 2012, 02:15 AM
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
9th February 2012, 07:33 AM
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
9th February 2012, 09:57 AM
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
9th February 2012, 11:54 AM
Cabot Stains Water-borne Polyurethane Product | Cabot (http://www.cabotstain.com/products/product/Water-borne-Polyurethane.html)

this stuff

Crunchie
9th February 2012, 12:08 PM
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
9th February 2012, 12:20 PM
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? :roflmao:





Sorry :B

Wizened of Oz
9th February 2012, 01:00 PM
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.

D700Doug
9th February 2012, 01:04 PM
OK thanks for that

I am far from a perfectionist :U

As long as it looks OK and works I am happy

The piece is old and I would not mind keeping some of that imperfect look to it .

If I need to I can top it with a piece of glass :p

D700Doug
20th February 2012, 03:09 PM
OK * sigh * I have been waiting for a dry ( less humid day ) but sucked it up and put the first coat on this morning, you could almost hear the timber sucking up the oil it was so dry, there were tiny bubbles coming out of the little surface cracks on the top and on the legs as the oil went in !!!!!

I used the Tung oil ( Kitchen Oil containing 90% tung oil ) turps polyurethane mix and so far it is looking good.

I will go and rub it back shortly but I doubt there will be much left on the surface to rub as it just soaked in so fast.

I will post some photos when I can

Many many thanks to all who have commented and advised on this !!!:2tsup:

cheers doug

Christos
20th February 2012, 06:16 PM
Too late now if you had not but if you had taken before and after photos would be nice.

D700Doug
20th February 2012, 06:59 PM
Too late now if you had not but if you had taken before and after photos would be nice.

Here are some I prepared earlier :q

http://farm8.staticflickr.com/7052/6908291407_a66b0b0440_z.jpg



http://farm8.staticflickr.com/7191/6908291597_af85688228_z.jpg


http://farm8.staticflickr.com/7181/6908291773_40c6510c13_z.jpg

:D:D:D



Ok not sure why they are not coming up as images but the links work to them

Christos
20th February 2012, 07:40 PM
I see them as images.

D700Doug
20th February 2012, 07:45 PM
OK on mine they are just links

Stupid interweb thing :~

I will take some "During " shots tomorrow

D700Doug
23rd February 2012, 09:25 PM
second coat
Rubbed the first back with fine steel wool and second coat went on easily
A few dry spots still but no where near as many as the first

The weather is better ( dry and warm ) so will let this dry off and hit it again :D


http://farm8.staticflickr.com/7185/6776757150_8183db17fc_z.jpg


http://farm8.staticflickr.com/7062/6922870825_c325d479a5_z.jpg

It has already started work in the studio before it is snaffled for the lounge room

http://farm8.staticflickr.com/7062/6922854531_d74e79c1d0_z.jpg

Jim Carroll
23rd February 2012, 09:46 PM
Doug when applying the first coat it is important to get the whole surface wet.

If the timber keeps sucking up the finish keep applying more till the surfaces stays wet. It will help to get an even finish.

As others have said have a cup of coffee then clean up all the excess before it goes tacky.

D700Doug
23rd February 2012, 09:50 PM
I slathered the surface untill it was totally wet and left for coffee

By the time I came back it had sucked sections dry

same with the second application, less but same, slathered wet, left to dry and found smaller sections sucked dry.

I will rub it back and keep applying untill it gets an even coating.

the timber is just bone dry.

Thanks for the tip :2tsup:

Christos
26th February 2012, 09:26 PM
Are you doing one coat every day or so?

I guess I am eager to see the finished result but then I recalled all good things take time.

D700Doug
26th February 2012, 09:54 PM
Yep I wait till it is dry and polish it back a bit and re coat

I stuffed up the last coat so will probably do a light sand and put on at least one more coat

It is looking good but the cloth I used left lint in the finish and a screwed up trying to get it out :doh:

Just one of the joys of woodwork !

If I do say so myself apart from the stuff up it is looking good