Since you do not know what kind of wood it is I will try to cover as
many bases as possible and see if we can come up with something for
your specific needs.
First of all, you may be surprised to learn that wood often lasts
outdoors for centuries without any treatment whatever. Of course the
type of wood makes a great deal of difference. The cracking is
caused by "dryness" rather than rot or decay. In Japan there are
wooden temples 1500 years old which are still solid structures and
many of them have had no preservative treatments at all - not even a
coat of paint.
If your statue is going to be displayed in a summy location, we need
to consider UV protection as well as moisture. If in the shade, the
UV protection is not as important.
The fact that the wood is dry (dry enough to crack) is something in
your favor - moisture causes rot by providing a comfortable home for
the bacteria attacking the wood.
Then there is "weathering" which is different than rot. Weathering is
erosion from sun, wind and debris. If wood is not protected by paint
or stain, the weathering process removes about one fourth inch of wood
per century from softwoods on vertical exposures.
So, when this narrows down to a suggested final treatment, apply that
treatment indoors before placing the statue in the yard so that there
will be no added moisture to be sealed inside the wood. Too many
people forget that when they seal or weatherproof wood, they are
sealing moisture "in" as well as sealing it out.
Now, I'm going to put on my archaeologist hat. If the wood is
cracked, leave it cracked. Please don't try to do any kind of
restoration such as filling the cracks, restoring color, etc. It may
(1) ruin the value and (2) actually create more problems than it
Of course, The best way to protect outside wood from weathering is to
cover it with a roof. A roof also prevents decay as long as there is
no other source of moisture, such as contact with the ground.
But I must presume there will be no roof.
Now you will probably throw rocks at me when I suggest the solution.
Based on the generalities we are working with here, I will recommend
the "archaeologist's friend" when it comes to general preservation for
Thompson's Water Seal.
It is stable, lasts a few years (re-apply according to directions) and
can be purchased in "colorless" formulations.
Now the best way to do this is to submerge the whole object in the
liquid. But since that may be impractical for you, use the softest
brush you can find and to get into the cracks and other detailed
places, use an "airbrush."
Old wood displayed out of doors from totem poles to Old Kingdom
Egyptian wooden ships have been treated with Thompsons to good effect.
The only difference between using it for "old" wood and slopping it on
a brand new wooden deck is the method of application.
On the deck, you can use most any ol' brush or roller. What you are
doing however, is archaeological preservation where the surface
condition of the object is fragile and you want to preserve as much of
the current "look" as possible. Camel hair brushes and the all
important "airbrush" for fine and detailed work where you need to
reach into cracks to ensure coverage.
As good as Thompsons has been, there is now a new latex formulation
which is even better than the old oil formulas. The latex provides
some UV protection and curbs mildew. The oil formulas might allow
some mildew growth which has a tendency to "grey" the finish.
I recommend the latex base.
Make sure you clean the surface before applying the sealant. Even the
cleanest looking wood can have a lot of dirt on it. In your case, use
a canned air product rather than any liquids. Apply the air jet
evenly and gently to avoid removing any paint there might be left from
the ancient coloring.
I have successfully treated wood 5000 years old in this manner.
You will need to repeat this process every few years.
I am glad you did not want the more permanent preservatives such as
those used in museum displays, etc as many of them are arsenic based
and pose a danger to the people handling them.
Thompsons it is.
Search - none
Simply advice from a retired archaeological technician.
If I may clarify anything, please ask.
Clarification of Answer by
12 Jul 2004 14:23 PDT
Use a cloth sling both to lower and raise the piece. Avoid ropes or
cord as they may "bite" into the wood. The cloth sling should be just
a little wider than the base of the statue in order to minimize any
tendency to "tip over."
When you have raised the statue, dry it in an upright position. That
way if there are any "flow" marks from wood color or old paint, they
will not show being 'counter' to the natural grain of the wood.
If there is any old paint on the piece, and I think you indicated
there was, use a cotton swab soaked in the Thompsons and test for
color fastness. If it runs or smears, you will be back to a soft
brush and air brush if you want to preserve the remaining color.
If the remaining color is not that important to you and you want it
removed, then remove it before you dip as that will also prevent color
'runs' down the piece. Look at it closely. Even though most of the
paint is gone, there may still be pigments 'hidden' within the wood
which won't show till it gets wet.
It is sort of like posting an answer here. I can look at it over and
over but the typos won't show till after I have hit the "submit"
button - - - then they all glare at me at once when it is too late to
do anything about it.
Hidden pigment can be much the same way.
If you would like, let me know when you are at each stage of the
process and we can take it one step at a time. Use the clarification
request as you did this time and I'll try to 'walk' you through the
whole thing if need be.