what to fill knot with

[ninjasnail]

Would like to get some advise on filling a knot in a piece of wood I am working with. I had read that a dark epoxy is best.

Anyone have an opinion about this?
Where can I get this dark epoxy wood filler in the Raleigh area?

 

[Bill Clemmons]

I usually start w/ a clear epoxy, then mix in something to give it the color I desire. I keep little bottles of various fine sawdust from different wood species. You can also use coffee grounds to darken it. Both the sawdust and coffee grounds can give it a textured look. Another way is to add some pigment. Think about artist paints, and stir in a little to color the epoxy.

 

[bob vaughan]

Epoxy and sawdust here also.
What size hole are you trying to fill? Large holes may not work well with epoxy. Also, the sides of the hole need to be free of debris commonly found in a knot hole.

 

[Westpacx3]

I usually start w/ a clear epoxy, then mix in something to give it the color I desire. I keep little bottles of various fine sawdust from different wood species. You can also use coffee grounds to darken it. Both the sawdust and coffee grounds can give it a textured look. Another way is to add some pigment. Think about artist paints, and stir in a little to color the epoxy.

I have used the epoxy with the powdered pigments but never with the dust. Is the epoxy and dust better than the titebond with dust?? That's what I have done when miters are off or I have small nicked corner.

 

[Craptastic]

If you are going to fill the knot with epoxy the best way to do so is

1. Clean up any loose material (bark, rot, whatever) as best you can as the first step.
2. Blast the immediate area with some dry compressed air to make sure that you got it all and that all dust is clear.
3. First seal the knot with a thin layer of epoxy that is painted in. This tends to help keep small bubbles from getting trapped at the spot (crevices) being repaired. A small torch while initial drying is a very good thing to use even on thin applications. A foam paint brush can help here too.
4. Actually fill the knot the rest of the way with an appropriate epoxy meant to address the size and depth of the pour. Some epoxy brands are better for shallow fills and some designed for deeper fills. All respond to using heat to pop bubbles. The foam brush may help here also. Bubbles may still try to cling to rougher surfaces.
5. A rather warm set up location is your friend.
6. A long set up time is usually best if you will need to machine or mill anything down.
7. Always remember that epoxy is usually still rather fluid for quite a while. This can be adjusted for by using different products from different manufactures so pay attention to the product you use and how you are using it for your needs. I have personally had epoxy pours that would still indent 6 months after pour from a heavy object sitting on them for a day. Depends on the product so choose wisely.

Oh, and I usually use liquid dyes and have occassionally used sawdust also to provide more texture. You have to be careful using sawdust if you are planing close to the finish thickness because sometimes it can cause small tearout.

Good luck and take before and after pics please.

 

[Jim Wallace]

I usually use the epoxy that comes in a tube from Klingspor. It comes in a variety of colors. The center of the tube is white surrounded by a colored outer layer. One part is resin the other is hardener. Cut off a little more than you think you need then knead it till the color is even. Work it like putty into your void. It’s supposed to be 5 minute epoxy. You need to finish working it before that, but it takes a little longer before you can plane or sand it.

Mohawk Epoxy Putty Stick

 

[Oka]

Epoxy, saw dust and epoxy dye to get a close match

 

[blackhawk]

I've used Alumilite Clear Cast from Michaels to fill knot holes and voids in my turned bowls. It works well. Any alcohol based dye can be used to tint the epoxy. Alumilite Amazing Clear Cast, 16oz.

For small cracks and holes, I use Starbond CA glue. They sell a brown and black CA glue that blends well.

 

[FredP]

If the knot is large you can drill a few small holes into the side of the knot. This will allow the epoxy to flow into the drilled holes and provide some bite. As the wood moves the patch can work loose over time. This extra bite will keep the patch from lifting.

 

[Roy G]

If the knot goes all the way through the wood be sure to put some tape on the back side or else you will have a mess. You could also consider a wooden patch cut to fit a recess made around the knot.

Roy G

 

[demondeacon]

I have had good luck with Timbermate products. Dries hard, sands easily and takes stain well

 

[Bill Clemmons]

I have used the epoxy with the powdered pigments but never with the dust. Is the epoxy and dust better than the titebond with dust?? That's what I have done when miters are off or I have small nicked corner.

Sorry, Jim, I can't say one way or the other. I've never used the Titebond w/ dust so I can't make a fair comparison.

 

[spartyon8]

I've used Alumilite Clear Cast from Michaels to fill knot holes and voids in my turned bowls. It works well. Any alcohol based dye can be used to tint the epoxy. Alumilite Amazing Clear Cast, 16oz.

For small cracks and holes, I use Starbond CA glue. They sell a brown and black CA glue that blends well.

I tried the Alumilite stuff and got very uneven results. Even after cured, I would find that I could leave a fingernail imprint. I now use a longer set resin (less air bubbles, more uniformity, etc.) when I decide to use resin. Lately, I have been using Knottec glue sticks and like them quite a bit.

 

[kooshball]

It might depend on what you are trying to accomplish design wise. At times I have filled voids and holes with epoxy putty colored to blend in visually with the wood and other times I have pigmented liquid epoxy to create contrast and a point of interest.

Most of the woodworking stores and maybe even a big box retailer will have some epoxy putty. Dry pigments may be more difficult to find locally but a woodworking store or Amazon should be able to provide some options.

 

[SabertoothBunny]

Something I enjoy doing with voids is filling them with a medium other than epoxy. Depending upon the wood and look your going with, you can do crushed stone like turqouise, man-made opal, crushed shells, etc and then use clear epoxy or thin CA to finish will the void and lock it all together. I find the crushed mediums add a lot of character and pop to projects.

 

[SabertoothBunny]

I tried the Alumilite stuff and got very uneven results. Even after cured, I would find that I could leave a fingernail imprint. I now use a longer set resin (less air bubbles, more uniformity, etc.) when I decide to use resin. Lately, I have been using Knottec glue sticks and like them quite a bit.

Alumilite has to be used with dry wood, little to no moisture. Moisture causes alumilite to not cure properly and in order to get clear results even when using dry wood it is best to use a pressure pot to get those air bubbles out. It was likely moisture from the wood causing the pour to not dry or set properly.

 

[mpeele]

Epoxy and Transtint Dye.