Frequently Asked Questions

Here are some Frequently Asked Questions answers on the Rangate Knot Filler.

Please feel free to submit your questions to or by giving us a call at 888-810-2522.


  1. How many holes can the Rangate Knot Filler fill?

    • Excellent question! We are talking about the volume of the void, so it depends. Each rod is about half inch in diameter and about 11 inches long. That make is about 2 cubic inches. Assuming the voids also about half inch wide and about a quarter inch deep, one can fill about 30 holes. Applying the Rangate Knot Filler with the right tools and at a steady flow while minimizing excess are the keys to good wood repairing.

  2. What do I need to use Rangate Knot Filler?

    • Aside from the rods, you'll need a Heat Gun, Cooling Block, and a Wide, Flat Chisel. These are required tools. Use your own or you can get one or all three tools from our store.

  3. Can I paint, stain, or varnish Rangate Knot Filler?

    • 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 the Rangate Knot Filler, then apply the filler, chisel away the excess, do the last 10% of sanding, then finish your piece.
    • How close to the color of my wood is the Rangate Knot Filler color of the same type?
    • 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.

  4. Is Rangate Knot Filler food-safe?

    • Rangate 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.

  5. Why is my Rangate Knot Filler bubbling?

    • Bubbles mean your rod is too hot. Turn your heat setting down a notch or two, and check the recommended temperature on your bag of Rangate Knot Filler. Heat it to that temperature range before use.

  6. Will Rangate Knot Filler prevent a crack in wood from expanding when filled?

    • Rangate 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.

  7. Can I use Rangate Knot Filler on pieces that will go outdoors?

    • Yes! The Rangate Knot Filler was originally developed for the boating industry, so getting wet is no problem. Just don't use it for applications it near any heat source (like next to a BBQ) or as a hot plate.

  8. Why do the colors have different melting points?

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

      285°F/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. Light hand sanding is recommended.

      320°F/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. They can be lightly sanded.

      410°F/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.

  9. Will Rangate Knot Filler work with my own Glue Gun?

    • To make sure Rangate Knot Filler can work with your gun, check that:
    • The heat gun is designed to work with half-inch (12 mm) diameter rods.
    • The heat 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 Rangate Knot Filler.

  10. How do I store unused rods?

    • Keep the unused rods in its original package and store them in a sealed poly bag at a dark dry place. Heat can melt the rods, and air will lessen its shelf life as the rod becomes rubbery, unsuitable for usage.

  11. How do I change the rods when it is halfway through?

    • 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.
    • See more detail instructions on the How to Use page.