Staining your Kayak
Using stains to add a little extra color to your boat.
There is no accounting for taste, but for some reason I find okoume a little bit boring. While the grain can be quite nice, the color is often a little bland. In my opinion it would often benefit from a little pumping up.
There are also times when I just don’t have a nice selection of wood strips. The tones and colors are all over the place and I’m not in the mood for making a complicated pattern to take full advantage of the variation. In this case I like to do something to unify the colors a bit.
The solution I arrived on was stain. A little bit of color can enrich boring okoume and even out distracting color variations. However, the stain needs to be compatible with epoxy because all of the wood will end up being covered with fiberglass and encapsulated in epoxy. Typical, traditional woodworking stains (such as MinWax) are oil based. The oils in these stains will interfere with the creation of a strong bond. You do not want to use oil based stains in combination with epoxy.
Instead you want to use a solvent based stain or dye such as a water-based or alcohol-based product. When the water or alcohol evaporates all that's left is the color. There are several products out there that fit this bill. The next requirement is that the stain be color-fast. In other words you don’t want a color that is going to fade or change the moment it is exposed to the bright sun. Many woodworking stains are intended for in door furniture that don’t see much direct sunlight and are not subject to fading. While there are still several products to choose from I settled on Behlen Solar-Lux Stain. It is an alcohol-based Non-Grain Raising (thus NGR) product designed for sun exposure. It comes pre-mixed and ready to use.
The benefit of alcohol over water-based is the alcohol does not raise grain. This is actually not a big benefit for a wood surface that will soon be covered with a thick layer of fiberglass, but it doesn’t hurt. The down side of alcohol is it evaporates very quickly, so you need to work fast to get a uniform, even tone. A water-base stain may provide a little more working time.
The best way to apply the stain is with a rag. Old t-shirts are ideal. Clean out the shirt drawer of some of those old 5K race or ugly office “Team-Building” retreat shirts. Cut them up in to several approximately 6” x 6” squarish pieces. Too big and the rag will soak up too much stain thus wasting it, too small and it won’t hold enough to go very far. Wet down the rag with stain by covering the top of the bottle with the rag bundled up into a ball. BTW, wear gloves while applying the stain. Anything that will stain wood will leave your hands a beautiful color for several days.
Start wiping down the wood with quick back-and-forth strokes along the grain. Due to the fast evaporation of the alcohol you need to keep the rag fairly wet. The stain should make the wood wet, soaking deep into the grain. As the rag dries out it will only make a dry colored smudge on the surface, leaving light spots in the deeper grain pores.
The wet look of the freshly applied stain will most closely match the finished color. As the stain dries it will lighten and appear less saturated. It may also appear quite blotchy. There are several ways to even out the color. One is to apply another coat of stain. Only do this if you feel the color when the stain was wet was not as deep as you desire. Don’t base this judgment on the dry appearance for the reason stated above, the dry color is deceiving. Another option is to wipe the boat down with solvent. Behlen’s offers a “Reducer” that will lift the color a bit and spread it around, but denatured alcohol will work. If you don’t want the boat any darker, use a fresh rag instead of the original you had used to apply the stain. The solvent will release any stain in the used rag resulting in a more color added. It is best to do this solvent wipe down before the stain has dried as the solvent does not need to work as hard to lift and move the applied stain.
The final, lazy way of making the applied stain more uniform is to apply a seal coat of epoxy. If the stain is still not fully dry, the epoxy will pick up some of the stain and move it around. This works with the alcohol based stain because the solvent is compatible with the epoxy. It will not work as well if the stain has dried completely.
Stitch and Glue
If you are staining a stitch and glue plywood boat, you need to apply the stain before any of the wood has been sealed with epoxy. This generally means before you glue and scarfs or puzzle joints, i.e. the raw panels before any assembly. Clean up the wood with a light sanding of 120 grit sandpaper stroking with the grain. The sanding is not strictly necessary, but does give you a chance to inspect the wood for printing or labels that you don’t want to show.
Sort through your pieces identifying the color you wish to make each piece. Sort each color into a separate pile. Identify the side of the part that should be stained. You don’t want to go through everything only to find that you stained the inside of the front left side of the hull, instead of the outside. Find a clean surface to work on that you don’t mind getting stained a bit. Use heavy paper to protect any surface you don’t want messed up.
If you are doing several colors, start with the lightest color. In this way, if you get any of the color on other parts the darker color has a better chance of hiding the mistake.
Stain each part, being careful to get to the edge of the part. You may find that the grain of some parts lets the rag slide more easily one way than the other, lift the rag and stroke in the easier direction so the grain doesn’t pull bits of lint off the rag.
Put each piece off to the side after it is stained. Don’t stack the parts one on top of the other as this may leave a mark as the stain dries. Also don’t stack the light colored parts under your work area as you apply darker stains as drips or splashes will leave permanent marks.
After I’m done staining the plywood I like protect the color under a seal-coat of epoxy. I use a paint roller to apply a thin, but complete coat of resin over all the stained surfaces. In this way you will be less likely to scratch off any color later in the boat building process.
After the boat is assembled you may need to touch up spots where the stain has been removed, for example, if you rounded over corners. I find the best way to re-coat these spots is to use a Q-tip as a brush. Only apply stain where stain has actually been removed, if you try to darken light spots cause by sanding epoxy on top of the stain you will just make a dark spot.
I’m often asked if it is possible to stain strips before installing them on the boat. Of course you can, but don’t expect the color to still be there when you are done. The stain does not soak in very deep at all. One stroke of a plane or sandpaper will remove most of the color. You need to apply the stain as the last step before apply an epoxy seal coat or fiberglass. Get your boat completely sanded prior to glassing and apply the stain at this point.
It is really not practical to apply more than one color to the surface. The low viscosity stain will soak under masking tape and bleed across any line you attempt to create. Plan on staining the whole deck or hull surface a solid color.
Apply the stain as directed and then proceed to the fiberglass or seal coat as you would have if you weren’t staining.
If you want some sort of accent that is not stained you can add it later. One technique is to add a thin strip on top of the hull sheer line after glassing the outside. Then glass the inside and the outside will be covered after gluing down the deck.
If you have a feature in the middle of the deck or hull that you don’t want stained, it may be able to scrape the stain off certain areas with a razor blade. Since the stain is not very thick on the wood, you don’t need to scrape much, but you will probably not want to do large areas this way.
It is important to remember as you select your colors that the stain will end up under several layers of fiberglass, epoxy and varnish. Because of this the color you see on bare wood will not match the color you will see on the finished boat. If you are trying to create a very specific color, you will want to create test panels with the complete coating schedule on top of it. A color that looks good on bare wood may change drastically with the addition of epoxy and then varnish.
Red pigments are notorious for fading, even when using a light-fast stain. I have used red tone stains frequently and really like the result, but if the boat is left outside for extended periods of time, the color will change and fade. I’m not sure how much of a problem this is as unstained wood will also change color when left in the sun too long.
Staining is a good way to add a little extra “pop” to your boat. It does complicate the process. If you are not comfortable in your ability to handle tricky tasks while working quickly, you may be better of sticking to the natural beauty of wood, but if you don’t mind a challenge, the results can be striking.