filling voids under marine varnish

[Southern Oregon Bob]

I've looked but I'm still confused. I used a cdx ply for my floor and sides. Now I want to use varnish on the top of the floor and under the alluminum siding for water protection. What is the best product to fill the large knot voids before varnishing. Will the alluminum sides show small imperfections from plywood below?

[asianflava]

Now I'm no woodworker, I just play one on the internet. Actually, I was killing time in a store. I started looking thru some woodworking magazines. Someone asked the same question, they suggested a "catalyzed adhesive" aka epoxy. If i were doing it where apperance didn't matter, I would thicken it to make it earier to work with.

As far as voids not showing up under the skin, I don't know.

[Southern Oregon Bob]

When you say epoxy are you talking about the little syringes full of epoxy glue from the hardwear store or does it come in other larger containers more suited for filling purposes?

[madjack]

...bob, goto your local hardware store and get some 2 part epoxy wood filler...mix it up, fill the voids, sand when dry. It is like bondo for wood, simply wonderfull
madjack

[doug hodder]

I should be a salesman for West Systems. 2 part epoxy, and can be thickened with either silica, microballoons, or low density fairing filler ( probably best in this case) You use it to fill areas that are low in fairing the hull of a boat. I've used it over areas as large as 2 sq. ft. You can buy small quantities, don't have to get a gallon of resin, but I do as I use it all the time. Mix it up, thicken it to like peanut butter and spread it in the voids with a squeege. sand off the high spots and you're ready to go. The system works great as you can use it for glueing, laying glass, top coats, bondo, and it can be drilled and tapped if need be. Doug Hodder

[Southern Oregon Bob]

Thanks maybe I'll try the West System. I tried the epoxy wood filler (smells like bondo) on my house thinking I was going the extra mile and most of it poped out in about two years. I had counter sunk screws on the verticles of a large wood railing and then filled in the 3/8", 1/4" deep holes, sanded, primed,and painted. 80% popped out as well as several crakes I had filled. It would still probably work on the TD floor or the sides under the allumunum skin.

[doug hodder]

West System has a free, at least I think it is, info sheet on how to use it. Their web site has all sorts of info on applications. If the material you're applying it to is dry prior to applying the product, you shouldn't have any problem. You can e-mail them and they have gotten back with me on any questions really fast. PS clean up requires at a minimum Lacquer thinner, Acetone is best, so wear latex gloves if that is a concern. The fillers are relatively cheap for what you are wanting to do, some guys throw in sawdust, sanding dust, etc... but I would go ahead and get the appropriate filler. Just my opinion. Doug Hodder