SDD

Self-Drilling Dowel

The CE marked SDD dowel is the ideal fixing for hidden connections in combination with aluminium connectors such as BTALU.
The double threaded dowel has a cylinder head with an T-40 6-lobe drive and the unique point design reduce the splitting in timber. The groove on the lower thread allows the material to be removed during installation.

Technical Data Sheet

CE Marking

Service class 2

Electrogalvanized steel 5µm

Indoor

Product Details

Images

Features

Benefits

CE-marked
No pre-drilling required
T-40 6-lobe drive
Small cylinder head for hidden connections
Groove for chip-removing

Material

Electro galvanised carbon steel

Application

Applications

Glulam beams
CLT wall to CLT floor

Suitable for

Concealed aluminium connectors

Technical Data

Dimensions

Product Dimensions

References	Item code	Diameter [d]	Length [L]	Head diameter [d_h]	Upper shank diameter [d₁]	Upper thread length [L_g2]	Lower thread length [L_g1]	Bit
SDD7.5X93	78119	7.5	93	12	6.9	27	8.5	T-40
SDD7.5X113	78120		113	12	6.9	36	12.5	T-40
SDD7.5X133	78121		133	12	6.9	36	12.5	T-40
SDD7.5X153	78122		153	12	6.9	36	12.5	T-40
SDD7.5X173	78123		173	12	6.9	36	12.5	T-40

Installation

The self-drilling dowel can be screwed directly through the wooden part to be assembled with the aluminium connector, without pre-drilling.

For installation with an aluminium connector, we recommend using a high-torque, low-speed screwdriver (600-1000 rpm). A pressure of 25 to 30 kg should be applied to the screwdriver after the drill tip comes into contact with the aluminium.

It is recommended to have a wood notch clearance of 1 to 2 mm, i.e. a notch of 7 to 8 mm for a 6 mm thick plate (BTALU type), to allow chips to be removed. The dowel must be perpendicular to the plate to be drilled.