Not only Battleships of WW I and WW II, but also Aircraft Carriers used to
have Teak decks. I don't know the point at which they went to steel, but Teak
was hard and would wear well, hence its use.
To the point, teak is oily and stable, therefore is a good wood for harsh
conditions. Wood primarily warps from moisture loss, the oily nature of Teak
slows the water loss process, therefore it resists warpage.Teak is fairly
stable and does not warp too much as it dries out.
UV is very damaging to wood, it dries it fiercely, causing small cracks
"checks". Before wood begins to check, it will usually turn a gray color, a
sign of UV damage. The Teak oil inhibits UV, and reduces moisture loss. The
application of Teak oil to the wood replaces what was damaged and removed due
to UV exposure.
Industrial coatings such as varnish filter UV and protect wood. Be sure to
use a "Spar Varnish" for maximum UV protection. Varnish also seals wood,
significantly reducing moisture loss. Be sure to varnish, oil, or whatever
equally to both sides of the wood, or there will be a large discrepancy in
the rate of moisture loss, and there will be warpage. The side of the wood
that is drying faster will shrink relative to the other side.
Plywood is very stable, but the thin veneer has a lot of surface area to
internal volume ratio and cracks very easily consequently. For plywood, the
surface must be kept coated and protected from UV, or it will check and may
delaminate. Again, what you do to one side you must do to the other in equal
proportion.
Prior to putting a finish onto an oily wood such as Teak, in order to have
good adhesion, wash the surface to be varnished with paint thinner and coat
within 2-3 hours. Same for surfaces to be glued.
My '77 Spit has the original dash in it, and it is Teak. I refinished it
about 5 years ago, used Spar Varnish. It is not properly stock now, since it
is shinier than the original matte finish--but I have a dash without cracks
in the finish and it looks great. I recoated it 2 years ago to refresh its UV
inhibitors.
Thanks for the opportunity to contribute to the list, I do not share the
apparant expertise of many here in the mechanical Q & A.
Michael
Godafoss@AOL.com
1977 Spitfire
1973 Stag
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