I have to fill a gap where birch plywood is joined with birch solid wood. The gaps are about 1/32. I have tried Elmer’s wood filler, as well as Zar wood filler, but upon drying both of them cracked (I assume from shrinkage). The birch is going to be left natural and finished with a WB clear poly. Since it is a light colored wood the gaps are noticeable and I would like to use a natural color filler. One thought I had was to finish it then use a wax filler.
Any thoughts???
Replies
Kaleo,
This, in my opinion, is about an impossible situation. There is no crack filler in the world that will either stay in the crack or look the slightest bit good once finished.
You'd be better off, again in my opinion, to give up on trying to hide the crack. Instead, make it a design element. Whenever I join a solid wood banding to a plywood edge, I always knock off the corner of both the wood and the plywood. This creates a visible, not unattractive, "Vee" joint between the two pieces.
If you've already glued the pieces up, you could run a vee router bit over the joint in order to create a shallow vee groove. You could also run it over a tablesaw blade to create a shallow cut, maybe at a 45 degree angle, to do the same.
Zolton
If you see a possum running around in here, kill it. It's not a pet. - Jackie Moon
Zolton,I've been reading your tag-line for sometime but never thought about it.We recently returned from New Zealand where I learned that a possum is way different then our opossum. Ours looks like a large, scabby, DUMB, rat. Theirs is a brown, furry, pleasant looking animal.In fact, they hunt these animals for their fur and have produced a blend of wool from Merino sheep and possum fur. It is marketed as Merino Mink - it very soft and very warm. Who would have thought - ?Frosty"I sometimes think we consider the good fortune of the early bird and overlook the bad fortune of the early worm." FDR - 1922
Frosty,
You won't find me cuddling up to any American opossums, that's for sure.
ZoltonIf you see a possum running around in here, kill it. It's not a pet. - Jackie Moon
You might try making your own filler out of white glue and very fine sawdust from the birch hardwood. Mix it well, then mix it some more to ensure the sawdust is well saturated. The paste should thick. Work it into the gap with a putty knife, let it dry thoroughly, sand, reapply, sand dry etc until the gap is completely filled.
You can try this on a small area first to asses the effect.
I don't know how much patina birch develops over time. If it does, any synthetic (ie non natural) filler will not change and over time the filler will become noticeable. Zolton's suggestion of accenting the joint would be a better solution.
Don
Kaleo,
It could be that the plywood is absorbing a lot of the solvent rapidly, leading to shrinkage. This isn't a problem I've ever encountered.
Another possibility is, of course, that your filler is not quite up to scratch.
You could try to scrape out any loose filler and refill. Hopefully some will have stuck to the plywood and will seal it.
After filling please make sure that you sand off any filler on the surface, otherwise, when you finish the piece the areas where there is any filler on the surface will show up as paler streaks which will accentuate the defect. Guess how I know.This also holds if you make your own filler because the glue will prevent absorbtion by the sawdust.
You can fill a flaw like this using hot melt putty sticks along with a good hot knife. Supplies are available at http://www.mohawkfinishing.com/
They require a bit of a learning curve but once you're comfortable with them, no crack, nail hole, knot, or other "flaw" will get the better of you.
"Flaw", that makes it sound like I made a mistake...:)Thanks for the infoKevin
On the contrary. Flaws are beyond our control. (The planer did it!) Whereas the things we do can be a: boo-boo, oops, dingus, or (my usual) oh-no-not-again!Now you have some insight as to why I have a bit of experience in fixing things.
I have successfully used epoxy mixed with a combination of wood dust and colloidal silica. When you mix epoxy and just dust, it darkens it up too much; the silica lightens it up a bit. You'll need to experiment a bit to get the right ratio. I start out with about 75% dust and 25% silica. Tape to either side to minimize sanding and let the epoxy form a "hill" over the gap. If the surface is horizontal, you don't need to thicken the epoxy a lot, just enough to change it's color and keep if from running. Let the epoxy harden a bit before removing the tape, but let it dry very hard before sanding.
What type of epoxy do you use?
Where do you find colloidal silica?
When it dries can it be sprayed with a WB finish or will it not be absorbed?
I have used West System epoxy in the past, but have recently swsitched to MAS epoxy. The MAS epoxy starts out thicker so it's easier to use for glue which is my main usage. Back to your project..... Any epoxy would work. If you don't plan to make a long term comittment to epoxy the dual cylinder syringes that they have at the big box stores work fine. Otherwise, you'll end up buying more than you need, pumps to dispense it and before you know it, you'll have the most expensice 1/8" X 1/8" repair known to man. That said, I use epoxy for all sorts of stuff from glue to putty to imbedding anchors in concrete. If you get the small tubes, be aware that the 5 minute stuff dries harder than slower curing varieties which makes it easier to sand, but remember when they say 5 minutes, they mean it. Colloidal silica is available anywhere that sells fiberglass supplies. I get it at places that sell boat building supplies, but there are places that sell it online. Here's one:www.jamestowndistributors.com. If you end up getting the silica at a fiberglass supplier, don't be tempted to get polyester resin to substitute for epoxy; they're not the same thing and polyester resin doesn't adhere well to wood. Lastly, it will not absorb finish no matter what type of finish you use. I've never used WB, so I can't speak directly to that, but I've never had problems with shellac or varnish. I can't imagine that you'd have a problem with poly over such a narrow space. I avoid using the epoxy/dust/silica on an oil finish. Because it doesn't absorb the oil, it creates a different sheen. It doesn't look awful, but it doesn't look great either.
Have you tried "Famo Wood" filler? It comes in several colors and can be mixed if necessary. You'll need to have some Acetone handy, cause the stuff dries really fast.
I've had good luck in "birch on birch" situations with the Maple, Birch, Natural, and/or "Maple/Alder" fillers. Depending on the color of the birch, you may need to mix and match some fillers, but you should be able to make the filled spots disappear.
Have not heard of that let I think I will try it. Of hand where do you buy it?I liked the idea of burn-in sticks but that would be too much, it's along a whole seam.
I get mine at my local ACE hardware or my lumber yard. The lumber yard has a wider color selection. You might try to Google "Famo Wood" and see if it's available near you.
"I liked the idea of burn-in sticks but that would be too much, it's along a whole seam."Why should the fact that it's a whole seam be a reason not to use the sticks? In order to make the repair visually go-away, you must blend a variety of colors... just like real wood. If you try to take the easy way out by simply using a monochromatic putty (any color) the seam will still jump out like a sore thumb. There have been times when I have intentionally extended a damaged spot or seam just so I could have more room to insert the filler. Nail or screw holes are some of the worst cases. They often are better repaired if the hole is made into a more irregular shape.
just make sure you get the right length.
Alan - planesaw
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