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Product categories:

Knot Filler               Powder Filler               E800             E850           Wood Filler               BCD360

Knot Filler

1. What kind of repairs is Knot Filler suitable for?
Knot Filler is suitable for all types of wood and hardwood and it is perfect for all kinds of repairs in wood, such as knots, cracks, edge repairs, corner repairs, cover-up of screws etc. Knot Filler is also perfect for formwork repairs and it has become a popular repair material in the formwork industry, watch youtube video.  
2. Why shall I use Knot Filler as apposed to epoxy?
There are several reasons why Knot Filler is preferable to epoxy, namely: 1) Knot Filler is non-toxic and therefore does not harm neither the environment nor the user, 2) Knot Filler is a faster way to repair wood, 3) Knot Filler is flexible and works with the wood, thus stays in the wood and does not crack 4) Knot Filler is ready to use - no mixing, 5) Knot Filler dries in seconds, 6) Knot Filler is UV proof, 7) Knot Filler accepts all kinds of surface treatments after sanding, and 8) Knot Filler is suitable for all kinds of repairs, no real limits to the possibilties of repairs with Knot Filler. 

3. Why do I get bubbles in my repair?
If there are bubbles in the Knot Filler when you have applied it to the repair, it is caused by one of the following factors: 1) The working temperature of the heating gun is too high, which causes the Knot Filler to boil and creates bubbles. It is important to follow the recommended degrees which are noted on the labels of the Knot Filler bags, and adjust the temperature if bubbles occur, 2) If the Knot Filler sticks have been exposed to air over time, it creates moisture in the Knot Filler sticks, which causes bubbles when you apply the Knot Filler. In order to prevent this, it is extremely important to close the Knot Filler bags tightly after use, as noted on the labels on the bags.   

4. Does Knot Filler sink?
No. Knot Filler does not sink when it is applied correctly. Hence, when you shoot the Knot Filler into the repair, let it cool down for a while, before you cut off the excess part, you will see a perfect repair. One of the big advantages with Knot Filler is that it does not sink over time. Temperature differences can though affect Knot Filler as it affects all other things. Therefore, Knot Filler might expand a bit in warm temperatures, whereas it might shrink a bit in cold temperatures when it is first applied. From our experience, the reaction does mostly occur in large-size repairs and does not occur in standard repairs. Another advantage of Knot Filler is that you can see the result of your repair instantly. It will not change character or sink later on the surface where it’s applied.

5. Does Knot Filler accept stain, oil, etc?
Yes. Just be sure to sand the repair first, as this "opens" the repair so it accepts any kinds of surface treatment. Surface treatment with stain can though be a bit complex, as the repair needs a more technical sanding method in order for the repair to accept the stain. Send us an email to info@woodrepair.dk if you have further questions. 

6. Can I sand the repair and what is the best technique?
When you have filled and cut the repair it is ready to be sanded. Sanding the repair is important as it ensures that the repair accepts the surface treatment you wish to use for aftertreatment. It does not matter whether it is oil, stain, laquer, paint - you can use any surface treatment you want, as long as you sand the repair first. The best technique is to sand the wood 90% first, before you start to repair the wood. When you have filled the repair with Knot Filler and cut off excess Knot Filler, you finish the last 10% of the sanding process. Make sure to use a good flow when you sand the wood and the repair, in order to let the repair "breathe" while being sanded.

7. Can Knot Filler be applied by machine?
Yes. Knot Filler in granulate form is perfect for semi- and full automatic machinery. We have positive experience with both semi- and full automatic machinery from Wintersteiger, and both types of machinery work perfectly with our Knot Filler and produce beautiful repair results. 

8. Does Knot Filler comply with industrial sanding machines?
Yes. Knot Filler is perfectly suitable for repairs that is sanded with hand machines and industrial machinery. The best and most professional results with Knot Filler are achieved with industrial sanding machines such as wide-belt sanders. Sanding machines by hand are also perfect for Knot Filler repairs, watch youtube video.

9. How do I change colour?
There are a few options to choose from in terms of changing Knot Filler colors. We recommend the following options: 1) Use different heating guns for different colors, 2) use our Knot Filler Saver to make new smaller Knot Filler sticks of the excess Knot Filler before you get the new color. Note: we highly recomment that you always try to plan your repairs so you make more repairs with the same color, and thereby minimize color change.

10. What is the best way to repair a long and deep crack / damage?
There are a few tricks that are nice to know when repairing a long crack or damage in wood. With these guidelines you will get the best result; 1) sand the wood 90-95% finish before you start to repair with Knot Filler, 2) fill the repair 2/3 with Knot Filler leaving the last 1/3 top without filler until is has dried, 3) when the Knot Filler is dry, you fill the last 1/3 of the damage, cools it down with a cooling iron, cut off excess knot filler and sand the repair. 

11. Do you have any certifications for Knot Filler?
Yes, Knot Filler complies with the IKEA test specification IOS-MAT-0054, and has been tested for Bisphenol A, Cadmium, Lead, Organotin, and Phtalates CPSC. Hence, Knot Filler is an environmentally friendly product that does not harm the user nor the environment. 

12. Can I use Knot Filler outside?
Yes. Knot Filler is applicable for both outside and inside repairs. Furthermore, Knot Filler is used in varies different climates ranging from cold climates in Russia, Finland, and Greenland to warmer climates in Turkey, Israel, South Africa etc. watch youtube video.

13. Why shall I choose Knot Filler to repair my wood? 
Knot Filler is flexible, strong, and durable at the same time. It is environmentally friendly and you can do all kinds of difficult repairs in few seconds! We developed Knot Filler in 1992 and it is the most unique wood repair product on the market. 

14. Where can I get Knot Filler?
We have distributors/dealers in more than 43 countries spread over Europe, America, Asia, and Africa. Find the complete overview of our distributors here, and find out where to buy Knot Filler at your location.  

Wood Mastic Powder Filler

1. What kind of repairs are Powder Filler suitable for?
Powder Filler is suitable for all sorts of repairs in wood. In general, Powder Filler can be characterised as an all-round paste filler that is perfectly suitable for various repairs and damages. Powder Filler is a high quality product that can be applied to damages up to 15 mm depth. It is a water-based paste filler, which means it is important to aftertreat the repairs with surface treatment in order to preserve the paste filler in the repair, or make sure the repair is not exposed to moisture and water. 

2. Can I mix my own color-combination?
Yes, you can easily mix your own color combination of the different colors of powder filler. There are eight different colours of powder filler, which you can mix and match exactly as you wish and thereby get the exact color you are looking for.

3. Can I add pigment to the Powder Filler?
Yes, if you wish to customize your Powder Filler even more, it is possible to add color pigments and create the exact color you wish. Use the white Powder Filler as a base to mix with any pigment. As an example, you can add silver or gold pigment to the powder and to create two very interesting colors.

4. Why does the mixed Powder Filler sink in the repair?
Powder Filler does not sink when it has been mixed correctly, according to our guidelines 3 powder to 1 water. Contrary, if you add water to the powder filler paste after you have already made a perfect paste that corresponds with the mixture guidelines, you will destroy the qualities of the powder filler paste, which will cause the filler to sink. Hence, it is not possible to recreate a smooth paste by adding more water after you have already mixed the paste and used it for some time. As mentioned, adding more water will destroy the qualities of the paste and you will not get a satisfying result.  

4. What is the expiration date of Powder Filler?
There is no expiration date on the "raw" Powder Filler. As long as the Powder Filler has not been mixed with water and is properly protected from any moisture, water or foreign objects there is no expiration date and you can store the powder for ages.

5. When shall I use Powder Hardener?
Powder Hardener is useful to add to the powder filler mixture when you wish to achive extra hard repairs. It is important to underline, that powder hardener is not neccessarry to add when using Powder Filler, however some wood workers experience a need for extra hard repairs, which makes powder hardener a perfect solution. If you brush your repair after the Powder Filler has dried, we also strongly recommend to add powder hardener to the powder filler paste. In addition, the powder hardener gives the powder filler paste an even better attachment.

6. The pot life is too short, what can I do?
If you find that the pot life is too short when you are working with the Powder Filler paste you need our quality P340 Powder Filler. The quality P340 has the same quality as our standard Powder Filler B2, however the drying time is significantly slower. Contact us at info@woodrepair.dk for more information about P340.

7. The drying time is too long, what can I do?
If you find that the drying time is too long, you need our quality B3 Fast Filler. The B3 fast filler has the same qualities as the standard B2 Powder Filler, however the drying time is significantly faster. As the drying time is faster, the pot life of the paste is likewise shorter.

8. Why are there cracks in my repair?
If you experience cracks on the filled surface after the powder filler paste has dried, it is because you have added too much water to the mixture. Make sure to follow the guidelines 3 part powder to 1 part water. For large repairs it can be useful to add Powder Hardener to the mixture to get an extra strong paste filler. 

9. How do I fill my repair in the best way? watch youtube video
When using paste filler there are different techniques to fill damages in wood. In order to use our paste fillers correctly (Powder Filler, E800, and Wood Filler) it is important to fill the damage with a 25-45 degree angle when you apply the filler with the spatula. When you use the spatula with a 25-45 angle, the paste filler will rise a bit on the repair, which means it does not sink when drying. Be sure not to fill so "clean" that the paste filler is even with the wood. 

10. Can I prolong the Powder Filler paste by adding more water?
No. As a standard rule you shall never add more water to the Powder Filler paste after you have mixed it with the correct dimensions of powder and water. When you use Powder Filler it is important to estimate how much you need to use and mix this amount. If you realise that you need more, we recommend you to mix a new fresh portion. Adding more water will destroy the quality of the paste filler, and it might cause the filler to sink or crack when it has dried. In this case, you need to start over and make a new fresh portion. An exception to this rule is, however, that within the first 5 minutes of mixing, you have the possibility of adding a lille bit more water to the paste. The reason is that the powder filler paste will settle within the first 5 minutes when you have mixed it, and if the paste becomes a little dry within these 5 minutes, you can add a little bit of water to get the right consistency without destroying the qualities of the paste. Bear in mind that this only applies within the first 5 minutes, after this you cannot add more water and thus need to start over with a new portion.

11. Can I aftertreat the Powder Filler paste with oil, stain, laquer etc?
Yes. Powder Filler accepts all kinds of surface treatments such as oil, stain, laquer, paint, wax etc. when the filler has hardened. 

Wood Mastic E800

1. What kind of repairs are Wood Mastic E800 best for?
Wood Mastic E800 paste filler is a high quality paste filler, free of any toxics and perfect for various kind of repairs and wood working segments. E800 is a ready-to-use paste filler which is water-based and water-repellant at the same time, which means it is perfect for both inside and outside repairs.

2. How is E800 better than other paste fillers on the market?
Wood Mastic E800 is a high quality paste filler that is 1) ready-to-use, 2) environmentally friendly, which means it does not harm the environment nor the user, 3) is both suitable for outdoor and indoor repairs, 4) both waterbased and water-repellant. The water-repellant effect makes it suitable for outside repairs.

3. Can I aftertreat it with oil, stain, laquer etc?
Yes. Wood Mastic E800 paste filler accepts all kinds of surface treatments such as oil, stain, laquer, paint, wax etc. when the filler has hardened. 

4. Can I use it for outside repairs?
Yes. Wood Mastic E800 is suitable for both indoor and outdoor repairs. Wood Mastic E800 creates an exceptional water repellency when the filler hardens, which means that it is perfectly suitable for wood repairs outdoors such as repairs in windows and doors. The E800 paste filler will even repel water and moisture wihtout finishing surface treatment. 

5. Do I need to wear protection gear when using Wood Mastic E800? watch youtube video
No, absolutely not. Wood Mastic E800 is a non-toxic paste filler made out of water and mineral components. It is therefore not neccesarry to use either a mask or gloves while using the paste filler. This also means that you will not have to use a mask when sanding, as the dust is non-toxic as well. In brief, harmless to both the user and the environment. 

6. Can I get a customized color?
Yes, if the amount is large enough. We have some clear minimum standards for producing new colors. Send us an email to info@woodrepair.dk if you are seeking a customized color and is prepared to take a larger amount.

Wood Mastic E850

1. What type of flooring is Wood Mastic E850 suitable for? watch youtube video
Wood Mastic E850 is the perfect paste filler for full-trowel filling of flooring. Wood Mastic E850 is a new recipe based on E800, however with a thinner texture and a longer pot life, which makes it easier to apply acroos the floor.
2. How is E850 better than other paste fillers on the market?
Wood Mastic E850 is a high quality paste filler that has been specifically developed to fill a whole in the market for full-trowel filling. It is a popular full-trowel filler in Denmark, and has been used in several high-end buildings. Only one full-trowel filling is neccesarry and the filler covers knots, scratches, holes, and other imperfections very effectively.

3. Can Wood Mastic E850 be aftertreated with oil, laquer, stain, etc?
Yes. When the E850 full-trowel filler has dried, sanded, and cleaned it is ready for surface treatment. Like our other paste fillers you can treat the finished repairs with any kind of surface treatment you wish. 

3. What are the advantages of Wood Mastic E850? 
The advantages of E850 are the following: 1) Ready-to-use paste filler, 2) minimal dust when sanding, 3) only one application, 4) accepts all kinds of surface treatments, 5) easy to get of skin and tools after use, 6) water repellent, and 7) environmentally friendly product without any toxics.

Wood Filler

1. What kind of repairs is the Wood Filler paste best for?
Wood Filler is is an alternative to other standard paste fillers on the market. It is a traditional paste filler of great quality. It is the perfect paste filler for those who are looking for a paste filler of good quality for few costs and it is suitable for various kinds of repairs. 

2. How is Wood Filler different from other paste fillers on the market?
Wood FIller is a ready-to-use paste filler, which comes in 10 different colors. It is easy and quick to use as you do not need to mix the paste first but can use it straight away. It is a traditional, fine-grained wood filler of very good quality to low costs.  

3. Can I use Wood Filler for outdoor repairs?
No. Wood Filler is only suitable for indoor repairs, not outdoor repairs. Wood Filler is a more simple and traditional paste filler, however of a very good quality. If you are looking for a paste filler to use in outdoor wood repairs our Wood Mastic E800 is the perfect choice. 

4. For what kind of repairs is Wood Filler most often used?
Our wood filler is very popular in the furniture industry where it is used for smaller repairs. Aditionally, Wood Filler is popular to use between grinding of many types of wooden objects. 

5. Can I aftertreat Wood Filler with oil, stain, laquer etc?
Yes. Wood Filler accepts all kinds of surface treatments such as oil, stain, laquer, paint, wax etc. when the filler has hardened. 


1. Why choose BCD360 compared to other heating guns? watch youtube video
The BCD360 Knot Filler gun has been specifically developed to our unique wood repair product Knot Filler. The BCD360 is a professional heating gun that is dependable for an all-day ongoing production, and it has a perfect ergonomic design. In addition, the BCD360 has an adjustable thermostat where you always know the exact working temperature. The nozzle is furthermore changable on the BCD360 and we carry different types of compatible nozzles. 

2. How do I make sure my Knot Filler gun does not brake down?
It is important to use the BCD360 as described in our BCD360 brochure and product description. There are a few easy and important rules to follow, otherwise the BCD360 Knot Filler gun can brake down in less than 30 seconds, when handled incorrectly. The following points are guidelines for what you must NEVER do with the BCD360; 1) never place the BCD360 on the side while it is still warm. This causes the Knot Filler to run back and destroys the Knot FIller gun. 2) never pull back the Knot Filler stick from the BCD360 gun. This destroys the Knot FIller gun. 3) never push the handle hard before the BCD360 has warmed up. The BCD360 Knot FIller gun needs a few minutes to warm up before you can use it (time depends on room temperature).

3. Why does my BCD360 Knot Filler gun not work? 
There are specific guidelines and rules to remember when using the BCD360, so it does not brake down. Find the guidelines in the answer above. If you experience problems, it is always a good tip to change the nozzle of the Knot Filler gun. 

4. What is the difference between the BCD360 and the BCD180 Knot Filler gun?
Both the BCD360 and BCD180 are heating guns are specifically developed for our Knot Filler system. In brief, the BCD360 is the professional Knot Filler gun that is necessary when making many repairs and working with the Knot Filler gun for several hours. The BCD180 is a smaller heating gun, suitable for private / DIY use when you only have few repairs. The BCD360 Knot Filler gun has an adjustable temperature which the BCD180 Knot Filler gun does not. Which Knot Filler gun that is most appropriate for you, depends on your need. Contact us for more information or advice on info@woodrepair.dk

5. Is there a waranty on BCD360?
Yes, as long as the Knot Filler gun has been used according to our instructions and guidelines. If the Knot Filler gun has been treated in an incorrect way that causes the heating gun to breake down, there is no warranty. The warranty does not hold if you have done the following with the Knot Filler gun: 1) pointed the gun in an upright position while still being warm, 2) placed the Knot Filler gun on the side while it is still warm, 3) pulled the stick out of the Knot Filler gun, 5) pushed the handle hard before the Knot Filler gun has warmed up. When the Knot Filler gun is handled correctly it lasts for years.

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