Aside from the rods, you'll need:

a) a temperature-adjustable glue gun capable of taking .5" diameter rods.


b) a cooling block which is larger than the void you're repairing. The block both packs the material into the void, and draws out the heat from the filler.

c) a wide, flat chisel to shave off the excess material after cooling the repair.


We carry these items, but you can use your own without any problems.

You can fill about 19 half-inch cube holes with one rod. Each single-color bag has 9 rods, each a 0.5 x 11.5".

Sure! Any way you currently finish wood will work with Knot Filler. Before applying the finish, lightly sand your repair to 'open' it to accept finish. Ideally, do 90% of your sanding before applying Knot Filler, then apply the filler, chisel away the excess, do the last 10% of sanding, then finish your piece.

While colors can be matched as close as possible, keep in mind that every tree, and piece of wood has variety in tone and color- sometimes within the same board! An exact, invisible match is unrealistic, but our colors offer a good approximation. Keep in mind when shopping online that digital displays often have subtle color variations based on the screen they are viewed on as well. We offer a starter pack for experimentation, which contains 4 of the most common colors to try.

Knot Filler complies with the IKEA test specification IOS-MAT-0054, and has been tested for Bisphenol A, Cadmium, Lead, Organotin, and Phthalates CPSC. While Knot Filler is non-toxic, it hasn't been tested by the FDA for food safety. We recommend you apply the finishing you would usually apply before using it in a food-prep piece like a cutting board.

Bubbles mean your filler is too hot. Turn your heat setting down a notch, and check the recommended temperature on your bag of Knot Filler. Heat it to that specific temperature before use.

Knot Filler is flexible and works with the wood. For an extra-wide and deep void, it's smart to use wood ties like you would with other repair options.

Yes! Knot Filler was originally developed for the boating industry, so getting wet is no problem. Just don't use it for applications it in extreme heat (like next to a BBQ).

The 3 different melting points have different material properties which make them more suited for some uses.

140°C Melting Point rods can be more easily cut and formed after solidifying. They’re useful for on-site repairs and turning projects, where you can fill voids in your material, and continue to turn the shape the piece afterwards.

160°C Melting Point rods offer a good balance of being able to be both cut and sanded. Because they’re so versatile, they’re an excellent choice for most users. Our two most popular colors, Black and Mahogany, are in this range.

210°C Melting Point rods can’t be easily cut after cooling. Because of their higher melting point, the material can be put through a wide-belt sanding production process. They are ideal for applications like flooring.

To make sure Knot Filler can work with your gun, check that:

i. The gun is designed to work with half-inch (12 mm) diameter rods.

ii. The gun is temperature adjustable and can heat to the temperature of the filler you want to use.

Any gun with both features will work with Knot Filler!

In general, we recommend avoiding removing the rod once it is in use. Instead of pulling the rod out, you can cut the rod at the opening where it is solid, and use the remaining portion later.


If you need to remove a rod, first heat up he gun to the recommended melting point. Pulling the rod out cold can damage the heating element, if the filler has solidified around it. Once the gun is hot, remove the rod. There will be some remaining filler in the gun- we recommend you use this before changing. If you are regularly using more than one color, we recommend you use a dedicated gun for each.