Interior Varnish General Forum Forums

Here is an article from beneteau about fixing dent nick and dings in the interior wood work on their boats. The color matching parts wouldn't be applicable for us but everything else should work help.

INTRODUCTION
During the past year we have found a few new items from our various wood repair
suppliers to make repairs. Although the basics have not changed, these new materials
can help make the task of repairing wood easier and more effective. The new items
have been included in the text and also in the supplies list on the last page of this guide.
BACKGROUND
The interior woodwork on a Beneteau is a combination of veneered hardwood plywood;
strip laminated trim, and solid hardwood trim. The wood is Douka. This wood is a
tropical hardwood related to the mahogany family; the species is Tieghemella Africana of
the Sapotaceae family. The finish is a two-part catalyzed polyurethane varnish that
contains a yellow colored stain.
Repairs to damaged areas can range from simple to quite complex. The characteristics
that you need to restore in a damaged area are:
Surface Smoothness – the finish must be leveled even with the surrounding area.
Sheen – a repair must match the semi-gloss appearance of the finish surrounding it.
Color – the repair must match or fit in with the color tones surrounding it.
There is not one easy method that applies to every repair. Experiment with the
techniques, and find what works well for you. If you would not undertake the refinishing
of your dining room table, call in a furniture repair technician for advanced repairs.
TO BEGIN
The first thing to be done is to determine the nature and extent of the damage.
Scratches and scuffs may only extend part way into the finish. If so, they can be fairly
easily repaired. Dents and gouges usually affect the underlying veneer or hardwood. If
this has happened the repair needs to include more advanced techniques.
Always start with a clean surface. Before beginning any repair it is necessary to be sure
no waxes or other contaminants are present on the surface to be repaired. If you begin
a repair thinking it will only be a simple touch-up, but end up needing to spray finish over
the repair; then your respray may be ruined if there is any residue from cleaners etc.
Wiping the area to be repaired with denatured alcohol is usually the best prep for
refinishing. However, if you have already resprayed the area, alcohol will damage the
uncured lacquer.
You are usually best off to minimize the area to be repaired. Try to not turn a small nick
into a repair the size of a life jacket. The exception to this rule is medium sized repairs
on a prominent surface such as the main bulkhead. In this case, respraying of the entire
area (usually one-half of a main bulkhead) is needed in order to achieve the best result.
This size of respray is best left to a wood finisher with spray experience.
LIGHT SCRATCHES AND SCUFFS:
Light scratches in the direction of the wood grain can sometimes simply be colored with
a felt tip touch-up marker. This is especially true when the scratch or scuff is on the edge
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of a molding or trim piece. The cherry marker from Woodworker’s Supply is a very good
color match. Most touch-ups done with a felt tip marker will require some blending
around the edges of the touch-up. This can be done using a clean cotton cloth.
Spraying one or two coats of lacquer over the touch-up will seal the surface. Scratches
across the grain usually require sanding of the finish to remove the scratch. It is best to
not sand all the way through the finish down to the bare wood. Remember that the
varnish contains color, so on a large surface you do not want to sand more than is
necessary. (On a small surface, sanding through the finish is not as much of a problem.
See the section on sanding under Filling). Better results will be achieved by also
minimizing the scratches produced by the sandpaper. Many light scratches can be
removed by only using very fine steel wool (Grade 4-0 or 0000). The dull surface left by
using steel wool can be blended into the surrounding finish by using polyester buffing
compound. We use Aquabuff 2000. A very small amount of compound rubbed on a dull
area (using a soft cotton cloth) can blend away steel wool scuffs in 15 to 20 seconds.
Don’t use too much compound or buff for too long. You are only trying to change the
surface sheen from dull to semi-gloss. If you buff a touch-up into a shiny spot, go back
to the steel wool and try again. An alternate method to complete a steel wool job is to
spray several light coats of lacquer. This will better hide a repair on a prominent surface
such as the main bulkhead than will a buffed spot. The next alternate method is to use
1200 grit sandpaper. As the grit on this paper fills in with the removed finish, it will
actually begin to buff the finish. A light compound buff or single coat respray will often
make this kind of touch-up totally disappear with a minimum of effort. Some scratches
can best be removed by a combination of sanding off some of the original finish, and
then building up new finish to fill in the balance of the scratch. This build-up of 3 or four
spot applications of finish is followed by sanding the respray to flatten the area, followed
by one or two additional coats of finish applied to a larger area. If steel wool or 1200 grit
sandpaper is not enough to remove a scratch, use a slightly more coarse sandpaper.
Most light scratches can be sanded out using 400 grit and 800 grit. Using sandpaper as
coarse as 320 will mean additional coats of lacquer will need to be applied in order to
cover the dullness caused by sanding. Many areas that need sanding can be finished
with 3 to 4 coats of lacquer applied after using the 400 grit, other areas will need finer
sanding with the 800 grit.
COLORING
As noted above, light scuffs and scratches can often be colored using a felt tip stain
marker. This is especially true when the damage occurs along the edge of a doorframe,
fiddle or other surface. The cherry marker from Woodworker’s Supply is a good color
match. Any local hardware store will also have an assortment of stain markers.
The most difficult damage to color is crazed varnish. When the varnish is scratched or
dented, the area that is crushed will turn a pale yellow color. This yellow color is the
result of fine cracks or crazes in the finish and is very difficult to color or hide. The felt tip
markers will only be successful on some crazed varnish. You often will have better
results applying color over the yellow area by using one of the varnish/stain pens. Be
careful using the varnish pen on top of fresh lacquer. If the lacquer has cured it is
possible to use the varnish pen on top of the finish. If the lacquer has not fully cured,
you are likely to get a reaction between the two materials. Using this pen requires
allowing the time for the stain/varnish combination to dry before attempts are made to
blend the touch-up and seal the surface. The color from the felt tip markers or the
varnish/stain pens can also be transferred to a cloth and padded onto a discolored area.
Both the felt tip and varnish pen markers will “take” better to a surface that has received
a coat or two of lacquer. When you are adding color to a damaged area, try to blend in a
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natural way into the wood grain around the area. This may include staining a grain line
into the wood several inches above and below the actual damage in order to conceal the
repair. If the end result looks natural and has a good finish on top of it, then it will not be
noticed as being a repair.
The graining pen is also useful. If an area has been filled with burn-in sticks or another
type of filler, adding some fine grain lines to the otherwise “flat” color may better mask
the repair.
We are often asked about the stain that is used in the Woodshop. The color that is
added to the varnish is more of a yellow coloring than it is a normal stain. If you sand all
the varnish off of a piece of the wood and then apply six to eight coats of lacquer; you
will have the same appearance as the original wood except it will appear somewhat
more reddish in color. The stain that is mixed into the varnish simply gives the wood
more of a golden cherry tone. In the past we have found that in many instances where a
piece of trim has a scratch or dent, it is possible to sand down through the varnish and
respray without ever adding color. As long as an entire length of a piece of wood is
sanded and refinished, the result will usually be acceptable.
Where color would be needed is when damage has occurred to a limited area of a large
surface. Sanding down through the finish in a small part of a large surface will result in
an unsightly off-colored spot. During the past year we tested a variety of Mohawk’s
colored finishes and discovered that the Light Golden Oak color is the best match for the
stain that is in the varnish from France. If used sparingly, this toner can restore the
golden color to a repair. On wood that has aged and is quite deep reddish in color, then
the Cherry toner will be necessary as a base color coat, followed by a light application of
the Light Golden Oak. To use these products, build up the finish over a repair until it is
nearly complete. Spray only a light amount and contain it to the area that actually needs
the color. Once the color matches, apply the final coats of Pre-Catalyzed Lacquer. Do
not apply any stain directly to bare wood, the results will not match the surrounding
finish.
DEEP DAMAGE
The first consideration with deep damage is whether the part can be repaired at all.
Sometimes the best result will be achieved by covering a damaged spot with something
that fits the appearance of the boat interior. This can be a screw, an added piece of trim,
a swivel light unit, etc. Beyond covering a severe damage spot, consideration needs to
be given as to whether the best result will only come from replacing the part with a new
piece of wood or trim. This is the case when no repair will truly conceal the damage.
Ordering a replacement wood component does take time and the color match will always
be a problem, but sometimes it is the only answer.
Begin all repairs with a clean surface. If the wood is dented, the first step will be to
attempt to raise the grain of the wood by using steam.
STEAMING WOOD
Applying steam to wood fibers that are dented or crushed will cause the wood to swell
and expand. This technique can sometimes raise the grain of the damaged wood to a
level where no additional fill material will need to be added. In more severe cases,
steaming will at least help to minimize the amount of filler needed. To begin, prick with a
pin, or sand, or lightly score the finish over the dent with a razor blade. This will make it
easier for the water to penetrate to the wood fibers. Dampen a cloth with water, place
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the cloth over the dented area of wood, and apply a hot clothes iron to the cloth to drive
steam into the wood. Several applications of steam over a period of 5 minutes to an hour
may be necessary in order to cause the wood to swell. Once the grain has been raised,
allow the wood to dry completely before sanding and refinishing the area. Be careful to
not discolor the wood or burn the surrounding finish with the iron.
FILLING & LEVELING
Areas that are indented below the surface need to be leveled using one or more of the
following methods:
Sanding: Small shallow indentations on shaped surfaces can often simply be sanded
away. If you have a shallow dent that is one inch long on the top edge of a galley fiddle,
the best repair will be to sand that section of the fiddle to remove the dent. Always try to
maintain the same profile, and don’t dish out a small area. In this example the result will
look better if you “fair” the indentation by sanding for six to eight inches on either side of
the dent. Refinish the top edge of the fiddle with six to eight coats of lacquer and the
repair will be invisible. This same technique can be used on other small surfaces such
as doorframes, cap trims and individual sections of hull liner planking.
Burn-In Sticks: Deep dents and gouges can be filled using a hot knife and lacquer
burn-in sticks. These sticks are hard at normal temperatures and are melted into an
area to be filled using a burn-in knife. A burn-in balm is applied around the filled material
so that excess material can be removed using the hot knife but without smearing the
excess around the repair. The fill is sanded flat to the surface and finished with lacquer.
Additional coloring and graining may be necessary on top of the burn-in in order for the
repair to look as good as possible. Burn-ins are a good way to fill a deep gouge, but it
needs to be understood that this material will not provide the same wood grain
appearance (sometimes called “flash”) as the wood surrounding it. When viewed from
different angles, a burn-in repair will look like a good color match from one direction and
a poor color match when viewed from a different position. Keep this in mind and strive
to have a burn-in repair look good from the direction it is most often viewed from.
You can also use clear and amber colored burn-in in the same manner as a varnish fill
(see below). Remove all damaged varnish from inside a dented or damaged area. The
amber colored sticks burn-in sticks match the varnish color and will allow a more rapid
filling of a dent than is possible using varnish for a varnish fill (see below).
Wax Fill: Wax wood fill pencils such as those made by Minwax are only useful to fill
small diameter holes that have adequate depth. The classic use of wax fill is to fill a hole
over a nail that has been “set” below the surface. Use of wax filler on shallow
indentations that are large in size, or on any edges, is not useful because of the ability of
the wax to be removed during cleaning operations later in the life of the boat. We use
Minwax Blend-Fil pencil numbers 5, 3 and 6. It is best to spray lacquer over a wax fill in
order to seal the surface and prevent it from attracting dust.
Varnish Fills: Depressions and dents can often be filled using a “varnish fill” technique.
This involves removing any discolored (crazed) varnish from the depression and filling
the area with finish. The fill itself is provided by applying multiple layers of lacquer or
varnish. The area is filled until it is above the surrounding surface, and then sanded
back flat to the surface. The trick to this technique is to apply adequate fill varnish to the
repair, allow sufficient time for it to fully cure (most finished shrink slightly during their
cure), and then carefully sand the repair flat without dishing out the surrounding finish.
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Several top coats of lacquer complete the repair. A good method that includes sanding
the fill without disturbing finish is as follows:
· Pick and/or sand away any damaged varnish
· Clean the surface
· Use masking tape to mask off as small an area as possible around the dent
· Fill the dent using varnish or lacquer
· Allow as much time as possible for the fill to cure: 3 to 4 days is best.
· Begin sanding the fill using 180 grit dry sandpaper wrapped around a small
flat wood block. This block sanding is done with the block riding on a single
layer of masking tape placed on either side of the fill.
· When the masking tape begins to wear away, switch to a finer grit. Sand
with progressively finer grits to remove the 180 grit scratches.
· Remove the masking tape when you reach 400 grit.
· Carefully level the edges of the fill to the surface. Sand using 400, 600 and
800 grit
· Respray the area using lacquer.
Epoxy Fills: In the rare instance where you have a piece of wood that is missing quite a
bit of material, but where it is also not in a highly visible area of the boat; you can
replace the missing wood with Mohawk’s epoxy stick. This material will bond to an edge
or corner better than a burn-in. It cures to a flesh tone color that will need additional
coloring and finishing. We would not recommend this product as a first choice or in
important areas of the interior due to the difficulty in matching color and grain.
Total Removal of Finish
In the rare instances where removal of the original finish is necessary over an entire
panel of the interior cabinetry, heat stripping is the easiest method to use. Careful use of
a heat gun and putty knife will result in a more rapid and more thorough removal of the
finish than is possible through sanding. Mask off the wood surrounding the panel to be
stripped. Use the low setting on a heat gun. Make sure the putty knife has a nicely
rounded edge so as to not gouge the veneer. Be careful to not overheat the surface.
The glue that bonds the veneers together will release if too much heat is applied. This
will result in a blister of the top veneer where it separates from the underlying wood.
Concentrating the heat gun in one place for too long can also burn the veneer. After the
finish has been stripped, sand the panel using 180 and 320 grit. Respray the panel to
match the surrounding finish by applying 4 – 6 coats of sanding sealer; block sand using
320 through 800 grit; tack cloth wipe; and 2 finish coats of pre-catalyzed lacquer.
RESPRAYING FINISH
Although the original varnish from France is available, we do not recommend using it.
We have found that much better results can be obtained using the aerosol Pre-
Catalyzed Lacquer products. To begin a respray, be sure you start with a clean surface
free of any contaminants. Use a tack cloth to remove any final dust from the surface. In
instances where you need to build up finish (as opposed to simply applying a final finish
coating), use Sanding Sealer for the early coats. Sanding sealer has more solids
content while also being formulated to aid in easy sanding. Apply lacquer using normal
spraying techniques:
· Shake the can to mix the finish thoroughly.
· Spray even coats, holding the can perpendicular to the surface at a distance
of about 9”. Spray each pass about 3” away from the previous pass. Spray
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in the direction of the wood grain. Spray enough finish to allow the lacquer to
flow out, while not applying enough finish to promote runs, sags and curtains.
· After spraying two to three coats, lightly sand using 800 grit dry sandpaper to
remove any dust inclusions.
· Vacuum and use a tack cloth to remove dust.
· Continue building up finish.
· Apply final coats using a double-coat technique. This is done by spraying a
light coat, allowing the solvent to flash off for two to four minutes, followed by
a medium coat. The second application flows out better without forming runs
because the light first coat is already partially dry.
· Between uses of the aerosol finish, clear the valve and pick-up tube by
turning the can upside down and spraying until finish is cleared out of the
valve.
· Always remove dust using a tack cloth prior to spraying.
Always wear a respirator when spraying finish. Provide adequate ventilation. Be
careful about the use of fans, motors and other spark generating devices while spraying:
lacquer fumes are explosive.
If you are respraying a large surface, be sure to begin with one or two full cans of finish.
Due to the expansion of the propellant, aerosol cans will provide a better finish when
they are full. Save your partial cans for small touch-ups.
Lacquer is sensitive to temperature and humidity. At high temperatures (above 95° F.)
the solvent will sometimes flash off so quickly that the surface skins before the coat
flows out. If this happens there will be an orange peel effect in the finish. This can be
sanded out with 400 or 800 grit using a hard wood backing block. High humidity will
cause moisture trapped in the respray to fog or form a white blush in the finish. The best
answer is to spray early in the day during summer months. Applying a coat of “No
Blush” on top of the recently sprayed material can help overcome both orange peel and
blushing. No Blush has more solvent and very little solids in the product. This means it
will slow down the drying of the lacquer and allow water trapped in the finish more time
to evaporate. This thinning of the finish also means that runs and sags will form more
easily, so use it sparingly.
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Material Sources: MOST ARE AVAILABLE AT THE LOCAL HARWARE STORE
OR A WOODWORKERS SUPPLY HOUSE.
Material Manuf. # Supplier Manufacturer Phone #’s
Pre-Catalyzed Lacquer Satin
P/N 297668
102-0412 Hardware
store or
Mohawk
Mohawk Finishing
Products
518-843-1380
Clear Lacquer Sanding Sealer
P/N 297667
102-0423 Same Mohawk
Light Golden Oak Ultra Classic Toner
P/N 454897
100-0415 Same Mohawk
Cherry Ultra Classic Toner 100-0408 Same Mohawk
Super Blush Retarder 103-0476 Same Mohawk
Beneteau Touch-up Marker – Lt. Cherry
P/N 454840
Beneteau
France
Beneteau Touch-up Marker – Dark Cherry Beneteau
France
Behlen Scratch Remover – Cherry 851-260 Hardware Woodworker’s
Supply
800-645-9292
Varnish/stain pens: Furniture Touch-up
Stain – Early American
10040 Hardware
store
Cecil James Paint
& Wallpaper
Center
843-423-5814
Furniture Touch-up Stain – Cherry 10010 Hardware or > Cecil James
Light Oak Graining Pen 265-0101 Hardware or> Mohawk
Behlen’s burn-in kit (incl. sticks & balm) 850-987 Hardware or> Woodworker’s
Supply
Electric Burn-in Knife 900-
EK24FC
Mohawk
Burn-in Balm 401-1203 Mohawk
E-Z Flow burn-in – Cherry
P/N 454686
315-0408 Mohawk
E-Z Flow burn-in – Light Amber Transparent 315-0009 Mohawk
E-Z Flow burn-in – Clear Transparent 315-0001 Mohawk
E-Z Flow burn-in – Dark Cherry
P/N 454685
315-0390 Mohawk
E-Z Flow burn-in – Champagne 315-0402 Mohawk /
woodworkers
Lt. Walnut burn-in stick 850-868 Woodworker’s
Supply
Dark Walnut burn-in stick 850-931 Woodworker’s
Supply
Cherry burn-in stick
P/N 454686
851-889 Woodworker’s
Supply
Wood Epoxy Stick 743-1500 Mohawk
Bend-Fil Wax Filler sticks: # 5 (best match),
# 3 (light), # 6 (dark)
Light Cherry P/N 270010
Dark Cherry P/N 006013
Hardware
store
Minwax Local
Hardware
Store
Aquabuff 2000 Polyester buffing compound Hawkeye
Industries
800-977-0060
Dull Aluminum Paint for older portlights &
annodized aluminum
1403 Hardware / K -
Mart
Krylon Local
Hardware
Store
White semi-gloss Enamel for Portlights 7797 K-Mart Rust-Oleum Local
Hardware
Store