The KNAPP®-Dowel is a strong and durable self-holding plastic dowel and available in 6×28 mm and 8×36 mm. It grips itself into the borehole due to its special design of threaded ribs and lengthwise groove, hence, no clamping of the workpiece needed. Unlike conventional wooden dowels, it has the option to be used with or without adhesive. Reduced manufacturing time and perfect for outside use are just two of the many benefits the KNAPP®-Dowel offers.
The KNAPP®-Dowel is a strong and durable self-holding plastic dowel and available in 6×28 mm and 8×36 mm. Consists of high-strength weather-resistant (POM) plastic and gripping itself into the borehole due to its special design of threaded ribs and lengthwise groove, hence, no clamping of the workpiece needed. Unlike conventional wooden dowels, it has the option to be used with or without adhesive. If used with the recommended KNAPP®-Adhesive PU+ (Z011/1) the lengthwise grooves and two holes ensure an optimal distribution of the glue and a firm anchoring in the material, hence creating a strong and tight connection between the components when hardened.
Features and Benefits:
- Design – the threaded ribs, lengthwise groove, and holes on both ends ensure:
- a strong anchoring in the material, hence depending on the applications and conditions it can be used with or without adhesive.
- optimal distribution of adhesive and prevent bulging of i.e. chipboards due to the swelling of wooden dowel.
- fast manufacturing as there is no clamping needed and immediately load bearing → especially beneficial for an automated manufacturing process.
- Material – high-quality polyacetal (POM) plastic, thus no shrinking and swelling
- no opening of the joint due to shrinkage and swelling behavior, even when exposed to the environmental humidity changes.
- weather resistant, thus suitable for outside applications.
- guaranteed quality no risk of breakage and cracking, as opposed to hardwood dowels (beech dowels, etc.)
- does not rot as opposed to wooden dowels
- KNAPP®-Dowels work very well for dowel machines. We recommend simple white glue (for example PVAc) for easy and simple cleaning of the machines.
- Not recommended to combine with wooden dowels
- Recommended to use with KNAPP®-Adhesive PU+ (Z011/1)
- Case goods and architectural millwork for any material where normal dowels are used
- Suited for outside use
- Windows and doors
- Especially popular for millwork on boats and areas of high humidity → due to it being lighter than a wooden dowel.
Case Goods and Furniture
Windows and Doors
- Predrill boreholes
- If used with glue – add KNAPP®-Adhesive PU+ (Z011/1)
- Insert KNAPP®-Dowel using a dowel insertion machine or hammer in by hand
- Assemble workpiece with a rubber mallet
- KNAPP®-Dowel grips itself into the borehole best when the borehole is just slightly less in diameter than the dowel. We recommend:
- 8 mm diameter borehole for the 8×36 mm dowel for dowel insertion machines.
- 5/16 (7.9 mm) diameter borehole can be used for the 8×36 mm dowel when inserting by hand (without dowel insertion machine) for a tighter fit if needed.
- 6 mm diameter borehole for the 6×28 mm dowel for dowel insertion machines.
- 15/64 (5.9 mm) diameter borehole can be used for the 6×28 mm dowel when inserting by hand (without dowel insertion machine) for a tighter fit if needed.
- Through the lengthwise grooves, the KNAPP®-Dowel has an oval shape and brings pressure only to two sides of the borehole walls (rather than all around), thus ideally when a KNAPP®-Dowel is set into the borehole on the edge of a board. It should sit so the pressure goes towards the lengthwise direction of the edge rather than towards to the edge.
- Due to the ribs on the dowel being threaded, the dowel can be screwed in an out. This is especially helpful if the dowel needs to be taken out after being installed.
Note for CNC machining centers and insertion of the KNAPP®-Dowels:
- The depth of the total borehole should be 1 1/4 – 1 3/8 in (32 – 36 mm) for the 6 mm dowel (K066/1) and 1 5/8 – 1 3/4 in (42 – 45 mm) for the 8 mm dowel (K067/1). The selected larger drilling depth ensures optimum distribution of the glue throughout the borehole. These total depths apply to both components that get connected.
- The diameter of the borehole should be 6 mm for the 6×28 mm dowel and 8 mm for the 8×36 mm dowel.
- When used with a CNC machining center, the drill hole on melamine or laminate surfaces should be chamfered 0.5 – 1 mm for better insertion of the dowel. This will ensure correct insertion without the dowel catching on the edge of the material.
- In case you are using an automatic dosing device, the glue quantity can be set optimally for the entire borehole space by means of the dosing setting. Optimum distribution of the glue is ensured.
- When using our dowel with a CNC machining center, we recommend using PVAc white glue. Optimal dosage is easily set via the system. It also ensures easy cleaning of the system.
- Tip: for 600 mm (material length) up to 6 KNAPP®-Dowel are recommended, depending on the material. Do not mix with hardwood dowels because of the differences in accuracy.
- Tip: For preparation work, please refer to the general instructions.