T.R | Title | User | Personal Name | Date | Lines |
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2110.1 | | DELNI::OTA | | Wed Apr 09 1997 10:02 | 20 |
| Pete
What kind of tung oil finish did you use. If it was straight tung oil
then rubbing out will be necessary.
I generally look at the first coat to see if any grain raised when I
apply tung oil If the grain raised I use 00000 steel wool to sand it
down. Other than that I actually use the same steel wool (clean piece)
to apply further coats.
After a couple of coats and I feel the finish is complete, I generally
don't add wax. I have though done that on a couple of pieces, using
Bri-wax. I am not sure what the manufacturer meant by rubbing out. I
generally buff the tung finish with steel wool to be sure that there
are no tacky spots left, I have never waited 72 hours to apply wax
either usually 2 days max. So I am not sure why your finish requires
so much time.
Brian
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2110.2 | Straight Tung Oil it is... | MROA::PVINCENT | | Wed Apr 09 1997 16:31 | 12 |
| Brian,
Thanks for the info. I forgot the brand I used, but it is "straight"
tung oil. So when you say "rubbing out will be necessary", what does
that mean? Is there some technique I'm supposed to do after the final
coat? Or does using steel wool to apply additional coats take care of
that?
I never used anything other than polyurethane before, so I'm a little
nervous about how this tung oil stuff is going to work.
Pete
|
2110.3 | finishing touches.... | PCBUOA::TARDIFF | Dave Tardiff | Wed Apr 09 1997 17:33 | 28 |
| I think traditional references to 'rubbing out' refer
to the final smoothing/polishing done on....traditional finishes.
You start with smooth wood surfaces, and apply layers of 'stuff',
of whatever type you prefer. Each layer will probably collect a little
dust, hair, have varying thicknesses...which is why you smooth each
one a bit with steel wool before applying the next one. The supposed
goal is a perfectly flat finish surface, to the touch and the eye (for
reflections).
Of course, steel wool is always pretty coarse, on an absolute
scale. To get the final perfect surfaces, you use pumice or rottenstone
(or in sequence) mixed with oil, applied with a block, to 'rub out' and
polish the surface. Each successive step removes any projections and
replaces big (relatively) scratches with smaller ones. Get the scratches
small enough and you get a smooth, reflective surface.
For instance - I often use wet-dry sandpaper, glued to a flat
surface (marble tile) to sharpen tool edges. Starting with 80 grit,
I get an obvious scratch/gouge pattern on the steel - when that is uniform,
I know it's flat to that level (80 grit scratches). Each successive grade
(100, 120, etc.) results in a finer scratch pattern, and each step should
remove any trace of larger scratches remaining. If I take this all the
way down to 2000 grit (11 steps with the grits I've got) I can get a true
mirror finish on tool steel - no naked-eye visible scratches at all.
Another example - what's the visible difference between a
spray-can-painted auto repair and a professional hotrod showroom finish?
Multiple thin coats and rubbing out....
|
2110.4 | Random jottings... | WOTVAX::HILLN | It's OK, it'll be dark by nightfall | Thu Apr 10 1997 08:22 | 17 |
| From what has been described, in some parts of the English speaking
world, rubbing out will be referred to as rubbing down.
For the first one or coats it will remove grain fibres that have been
lifted and project above the mean surface. On later coats use finer
and finer abrasives to get a better and better finish.
Car sprayers also use many coats of paint which progressively have less
paint and more thinners to give a finish with great 'depth' and high
gloss. They rub out/down between each coat. When last I heard, Rolls
Royce used 27 coats of the final colour, with the last coat have over
90% thinners in it.
Some years ago, I got a great gloss, depth of finish and durability
with 7 coats of polyurethane varnish on a dining table.
Nick
|
2110.5 | | DELNI::OTA | | Fri Apr 11 1997 14:00 | 15 |
| My error in my description I left of the last steps. First coats 1-4
are put on with steel wool. A XXXXX brand is like 220 grit or better.
I then after coat 5 drys use a felt pad and rub in pumice with parafin
oil. After that is done and painstakingly remove all the pumice. I
then rub in rottenstone and then wipe that off.
I once tried using pure tung oil and found it took too long to set up
and had sticky or tacky spots. I moved to polymzed tung oil (varnish
resins are added) and found much much better results.
Hand rubbing the finish with pumice then rottenstone is a very long and
laborious not to mention boring process, but once you remove the
rottenstone you get a deep luster thats baby bottom smooth.
Brian
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2110.6 | Cleaing off the pumice/rottenstone? | MROA::PVINCENT | | Fri Apr 11 1997 15:13 | 6 |
| Thanks to all for the help....and one last question. I bought
pumice/rottenstone to use for the "final" steps. What is the best was
to "painstakingly remove all the pumice"?
Pete
|
2110.7 | | DELNI::OTA | | Mon Apr 14 1997 12:30 | 12 |
| Pete
First thing is to have lots and lots of paper towels. I use clean
rubbing oil and clean towels, wipe the entire bench down. Then again
clean oil and more paper towels and then more clean oil and more paper
towells, you get the picture. It takes a bit of time to remove the
grit, but you can feel it easily enough to know if there is any left.
The last thing I like to do is add a layer of lemon oil. It imparts to
me a nice luster and it smells nice too.
Brian
|
2110.8 | Tung vs Danish Oil | GROOVE::DADDIECO | That's Just The Way It Is ..... | Fri Apr 25 1997 09:50 | 6 |
| Anyone out there have experience with both Tung Oil and Danish Oil?
Being very new to woodworking I'm trying to understand the differences
between the two products. I would appreciate reading any comments and
comparisons you all care to offer!
Thanx .... d.
|
2110.9 | | NEWVAX::LAURENT | Hal Laurent @ COP | Fri Apr 25 1997 10:29 | 19 |
| re: .8
> Anyone out there have experience with both Tung Oil and Danish Oil?
> Being very new to woodworking I'm trying to understand the differences
> between the two products. I would appreciate reading any comments and
> comparisons you all care to offer!
"Danish Oil" doesn't really have a canonical meaning. Products labelled
"Danish Oil" are really an oil/varnish blend. I don't remember if the oil
component is tung oil or linseed oil or either.
Many finishes labelled "tung oil finish" are also usually really oil/varnish
blends. It's possible to buy straight tung oil, but it's considerably more
expensive than the blends.
I highly recommend getting a copy of Bob Flexner's "Understanding Wood
Finishing". It does a pretty good job of explaining these things.
-Hal Laurent
|
2110.10 | ex | DELNI::OTA | | Mon Apr 28 1997 08:54 | 14 |
| I have tried both. I found pure tung oil takes a long time to dry and
can pool up and get tacky in the grain differences in wood. I switched
to polymzed oils like Watco. These add varnish resins that make the
oil dry quicker.
In my living room I have a sofa table with Watco and a coffee table
with Tung oil. You can't tell the difference in finish.
I highly recommend tung oil as a finish because you see the wood and
can feel the texture over any other type of finish. One trouble is it,
is not as durable as say polyurethene and needs to be reapplied every
now and then, but the finish to me is worth the extra work.
Brian
|